Cadmium selenide quantum dot-zinc oxide composite: Synthesis, characterization, dye removal ability with UV irradiation, and antibacterial activity as a safe and high-performance photocatalyst

Advancements in the extraction, characterization and function activities of polysaccharides from Physalis L.: A review

Physalis L. primarily including five species (P. alkekengi, P. minima, P. angulate, P. pubescens, P. peruviana), with a long history of medicinal and edible use in Asia. The fruit of such plants are not only juicy and appealingly sweet and sour but also an excellent source of vitamin C and dietary fiber, making it popular choice in Northeast China. Polysaccharides are among the key active ingredients in Physalis L. plants and have attracted significant attention from researchers due to their diverse biological properties, including anti-inflammatory, antioxidant, immunomodulatory, antibacterial, hypoglycemic, and prebiotic activities. Numerous polysaccharides have been successfully extracted from Physalis L. plants over the past few decades, highlighting their potential in health and nutrition. Despite these advances, there remains a significant lack in the comprehensive evaluation of the extraction processes, intricate high-level structures, and structure-activity relationships pertaining to Physalis L. polysaccharides (PLPs). Given the significance of PLPs in the food industry, biological studies, and drug discovery, a systematic review of PLPs is imperative. This review aims to consolidate existing knowledge regarding their extraction, purification, structural characteristics, functional activities, and potential applications. This provides valuable insights for the application of PLPs in fields such as medicine, functional foods, and cosmetics.

Metal-organic cages based catalytic hybrid hydrogels for enhanced wound healing: Antibacterial and regenerative effects of Zr-MOC/chitosan composites hydrogel

Metal-organic cages (MOCs), assembled by the coordination of metal nodes with organic ligands, offer excellent solvent dispersion, functionalization potential, and abundant binding sites, making them ideal for hybrid hydrogel synthesis. Herrin, a novel Zr-MOC/CS hybrid hydrogel was developed by crosslinking Zr-based metal-organic cages (Zr-MOC) and chitosan (CS) using dibenzaldehyde-functionalized polyethylene glycol (DF-PEG) as crosslinker, marking the first instance of incorporating Zr-MOC into a hydrogel matrix. The composite hydrogel leverages the catalytic activity of Zr-MOC to convert trace H2O2 into hydroxyl radicals (·OH), delivering enhanced antibacterial performance. Characterization via XRD, FT-IR, XPS, SEM and SEM-EDS confirmed the successful integration of Zr-MOC within the hydrogel matrix. Antibacterial assays demonstrated superior efficacy against Escherichia coli (E. coli) and Staphylococcus aureus (S. aureus) compared to conventional hydrogels. Cytotoxicity tests (MTT and live-dead staining) confirmed excellent biocompatibility. Furthermore, in vivo experiments using an infected wound model revealed that the Zr-MOC/CS hydrogel significantly accelerated wound healing. These results highlight the potential of Zr-MOC/CS hydrogel as a multifunctional wound dressing material for antibacterial therapy in clinical applications.

Dual functionality of chitosan and CTAB doped SnSe nanostructures: RhB decolorization, oxygen evolution reaction and antimicrobial activity against S. aureus by inhibiting DNA gyrase through molecular docking

The current study explores the amalgamation of varying concentrations 2 and 4 wt% of chitosan (CS) and fixed concentration (3 wt%) of cetyltrimethylammonium bromide (CTAB) in tin selenide (SnSe) to form a novel ternary system of CS/CTAB-SnSe via co-precipitation method. The objective of this work is to minimize the minacious environmental concerns regarding organic pollutants and oxygen evolution reaction (OER) activity. This ternary system also used to examine the antibacterial action with familiar antibiotic ciprofloxacin (CIP) against a Gram-positive multiple drug resistant (MDR) bacteria Staphylococcus aureus (MDR S. aureus). The highest (80 %) decolorization efficiency of RhB was observed in an acidic medium at 8 min. For OER, optimized (4 wt% of CS doped into CTAB-SnSe) electrocatalyst revealed lower overpotential, minimal Tafel slope, and lowest Rct value, indicating higher OER activity. The optimized sample showed a maximum inhibitory zone value of 5.45 ± 0.04 mm against S. aureus. The docking investigations were undertaken to investigate the microbicidal prohibitive mechanism of CTAB-SnSe and CS/CTAB-SnSe on DNA gyrase enzymes in S. aureus. The experimental findings elucidated that CS augmented CTAB-SnSe exhibits significant active sites required for chromophore breakdown of RhB and inhibiting the growth of MDR S. aureus.

The role and mechanism of selenium in the prevention and progression of hepatocellular carcinoma

Hepatocellular carcinoma (HCC) represents the most prevalent form of liver cancer. Despite notable advancements in therapeutic strategies, HCC continues to pose significant public health challenges due to its rising incidence and high mortality rates worldwide. Selenium is an essential trace element that playing a critical role in human health. Recent studies have highlighted its potential preventive and therapeutic benefits in the context of HCC. However, some in vitro and in vivo investigations have yielded inconsistent results, and the mechanisms by which selenium influences HCC are still not completely clear. This review begins by providing an extensive evaluation of the effects and mechanisms of selenium on the primary risk factors associated with HCC, including viral infections, metabolic abnormalities, and lifestyle factors. Subsequently, we outline the roles and mechanisms by which selenium influences the proliferation, metastasis, and immune microenvironment of HCC. Finally, we emphasize the imperative for further investigation into the optimal dosage and forms of selenium, as well as its effects on the HCC microenvironment, to inform the development of effective clinical strategies. This review thus provides a foundational framework for the potential clinical application of selenium in the treatment of HCC.

Experimental determination of the mechanical and hydrolytic properties of chitosan/rice husk ash composite membranes

Chitosan-based membranes are promising alternatives to synthetic membranes in a number of specialized use cases, including water purification and electrochemical devices. In application, excessive swelling when hydrated can lead to poor mechanical integrity, necessitating modifications to the polymer so as to counter this effect. Embedding inorganic fillers within an organic polymer matrix is one method of combining excellent mechanical stability with good performance. This study investigated the effect of rice husk ash (RHA) on the mechanical and hydrolytic properties of chitosan-based composite membranes. We incorporated varying amounts of RHA into a chitosan solution and prepared thin film membranes via solution casting. We performed structural, chemical, and mechanical characterizations on the ash and membranes, observing 82.84 % water uptake in the 1.5 weight percent (wt%) RHA-doped membrane and 13.93 MPa tensile strength in the 2.0 wt% loaded composite. As the RHA content increased, the swelling ratio of the composites with RHA loadings greater than 1.0 wt% decreased, indicating an enhancement in mechanical strength. The observed results demonstrate that combining improved mechanical strength with increased water absorption and reduced swelling can lead to optimal membrane characteristics.

Efficient rhodamine B dye photocatalytic degradation in aqueous media using novel ZnO nanomaterials co-doped with Ce and Dy

Water pollution caused by dyes and industrial wastewater poses a significant threat to ecosystems. The purification of such pollutants presents a major challenge. Photocatalysis based on semiconductor materials is a potential wastewater treatment process due to its safety and cost-effectiveness. In the present work, Zn1-2xCexDyxO (x = 0.01-0.05) semiconductors were prepared by the sol-gel auto-ignition method. The samples are denoted CDZO1, CDZO3, and CDZO5 for x  = 0.01-0.05, respectively. The X-ray diffraction and Raman spectroscopy results revealed the formation of ZnO hexagonal phase wurtzite structure for all synthesized compositions. Different structural properties were determined. It was found that the lattice parameters and the unit cell volume increased, while the crystallite size diminished as x varied from 0.01 to 0.05. Transmission electron microscopy observations confirmed the formation of nanoparticles with the desired chemical compositions. The specific surface area (SSA) values are found to be 39.95 m2/g, 48.62 m2/g, and 51.36 m2/g for CDZO1, CDZO5, and CDZO5 samples, respectively. The reflectance spectra were recorded to examine the optical properties of the different nanoparticles. The values of the optical band gap were 3.221, 3.225, and 3.239 eV for CDZO1, CDZO3, and CDZO5 samples, respectively. In addition, the photocatalytic performance towards RhB dye degradation for the different samples was assessed. It was established that the CDZO3 sample with a moderate SSA value exhibited the superior photocatalytic performance among the other as-prepared samples wherein the percentage of degradation efficiency, and kinetic constant rate attained their maximum values of 98.22 % and 0.0521 min-1, respectively within 75 min. As per the obtained findings, it is evident that the Zn1-2xCexDyxO photocatalyst has prominent potential for use in the degradation of dyes and offers a useful route for impeding the recombination of electron-hole pairs of zinc oxide material.

Chitosan adorned with ZIF-67 on ZIF-8 biocomposite: A potential LED visible light-assisted photocatalyst for wastewater decontamination

The current investigation has utilized a simple and constructive stratified method to synthesize a binary (Cs/Z-8: chitosan (Cs) and zeolitic imidazolate framework-8 (Z-8)) and ternary Cs/Z-8/Z-67 (Z-67: ZIF-67) biocomposites at room temperature. A certain amount of Cs/Z-8 (0.05, 0.1, and 0.2 g) was used to prepare ternary biocomposites (denoted as Cs/Z-8/Z-67-0.05, Cs/Z-8/Z-67-0.1, and Cs/Z-8/Z-67-0.2, respectively). The synthesized materials were characterized. Through the adornment Cs, a non-toxic biopolymer, with Z-8 and Z-67, the desired efficacy in removing pollutants (TCN: Tetracycline, AB92: Acid Blue 92, and MB: Methylene Blue) was achieved under LED visible light. TCN removal in the presence of visible light by Cs, Z-8, Cs/Z-8, Cs/Z-8/Z-67-0.05, Cs/Z-8/Z-67-0.1, and Cs/Z-8/Z-67-0.2 was 22.6 %, 47.3 %, 69.0 %, 77.0 %, 95.5 %, and 65.0 %, respectively. The trapping test showed that TCN degradation by adding ascorbic acid, methanol, and IPA was 44.8 %, 66.9 %, and 78.5 %, respectively. It could be concluded that the O2- play the decisive role for the destruction of TCN. The reusability of Cs/Z-8/Z-67-0.1 as a photocatalyst indicated that it had the capability to preserve its stability and performance for three successive cycles of use (95.5 %, 89.0 %, and 84.0 %). Also, Cs/Z-8/Z-67 had dye degradation ability (39.0 % for Methylene Blue and 81.0 % for Acid Blue 92).

Robust regenerable metal-selenide-chitosan photocatalyst for the effective removal of Bromothymol Blue (BB) from wastewater

Water scarcity has been a crucial debate in recent years regarding the critical scenario of water pollution. The water body is continuously contaminated by organic effluents of textile industries, including pigmented dye pollutants. To tackle water bodies contamination, there is a need to develop an eco-friendly and efficient method for removing toxic dyes. Herein, ternary metal selenide nanocomposites of barium nickel selenide (NBSe-NPs) were synthesized by the solvothermal method supported by chitosan microsphere (NBSe-NPs-CM). Recovery of the catalyst was convenient by capping nanoparticles in the microsphere to maintain effective stability, biocompatibility, and well-designed surface coating. FTIR spectrum verified nanocomposite synthesis and chitosan microsphere (NBSe-CM) formation. SEM observations of nanocomposites and NBSe-CM indicated an average size of 13.78 nm and 253 μm, respectively. The presence of barium, nickel, and selenium elements in the NBS-NPs was verified by EDX analysis. The nanocomposites had a crystallite size of 15.73 nm. The photocatalyst exhibited a narrow bandgap of only 1.3 eV based on Tauc's plot. In addition, the synthesized microsphere demonstrated an efficient photocatalytic degradation (97 %) of Bromothymol Blue dye within 100 min under optimized operating conditions (pH of 6.0, dye concentration of 40 ppm, catalyst dosage of 0.25 g). The photocatalysis process followed the pseudo-first-order kinetics. The repeatability studies showed a slight decline in the catalyst's efficiency after four successive cycles. The DFT study shows that the NBSe-CM is energetically stable with more considerable negative binding energy, and the dye molecule interacts more strongly with the NBSe-CM surface. The findings highlight the exceptional characteristics of the newly designed ternary-metal-selenide-containing chitosan-microspheres for degrading dye contaminants from textile effluents.

Characterization and Antibacterial Activity of Silver Nanoparticles Synthesized from Oxya chinensis sinuosa (Grasshopper) Extract

In this study, silver nanoparticles (AgNPs) were synthesized using a green method from an extract of the edible insect Oxya chinensis sinuosa (O_extract). The formation of AgNPs (O_AgNPs) was confirmed via UV-vis spectroscopy, and their stability was assessed using Turbiscan analysis. The size and morphology of the synthesized particles were characterized using transmission electron microscopy and field-emission scanning electron microscopy. Dynamic light scattering and zeta potential analyses further confirmed the size distribution and dispersion stability of the particles. The average particle size was 111.8 ± 1.5 nm, indicating relatively high stability. The synthesized O_AgNPs were further characterized using X-ray photoelectron spectroscopy (XPS), high-resolution X-ray diffraction (HR-XRD), and Fourier transform infrared (FTIR) spectroscopy. XPS analysis confirmed the chemical composition of the O_AgNP surface, whereas HR-XRD confirmed its crystallinity. FTIR analysis suggested that the O_extract plays a crucial role in the synthesis process. The antibacterial activity of the O_AgNPs was demonstrated using a disk diffusion assay, which revealed effective activity against common foodborne pathogens, including Salmonella Typhimurium, Escherichia coli, Staphylococcus aureus, and Bacillus cereus. O_AgNPs exhibited clear antibacterial activity, with inhibition zones of 15.08 ± 0.45 mm for S. Typhimurium, 15.03 ± 0.15 mm for E. coli, 15.24 ± 0.66 mm for S. aureus, and 13.30 ± 0.16 mm for B. cereus. These findings suggest that the O_AgNPs synthesized from the O_extract have potential for use as antibacterial agents against foodborne bacteria.

Transformative enhancement of cellulosic textile properties via metallic oxide deposition: Comprehensive analysis of structural, optical, and thermoelectric traits

This novel research addresses the critical need for sustainable and efficient materials, aiming to enhance the optical and thermoelectric properties of Aluminum doped Zinc Oxide (Al-doped ZnO) on cellulose fabric for diverse applications. At first stage, Cellulosic fabric of Al-doped ZnO were experimentally studied in detail with respect to varying levels of annealing temperature. Structural analysis unveiled structural evolution in hexagonal crystal formations with a reduction in particle size up to 27.5 % on average, with increased temperature. Further, Raman spectroscopy revealed the doping effects on the vibrational modes of ZnO, potentially due to alterations in lattice structure. The ZnO optical modes are found as E2 (low) = 110 cm-1 with observed phonon frequency in the Raman spectra of ZnO at A1 (TO) = 364 cm-1. Fourier transform infrared spectroscopy (FTIR) revealed the presence of characteristic stretching of developed material. Furthermore, the optical characters revealed a decrement of 43.22 % in bandgap values with increasing annealing temperature. The analysis of thermoelectric attributes documented that the prominent sample annealed at 300°C exhibited the maximum Seebeck coefficient and power factor of 2.1 × 10-3 μV/oC and 5.8 × 10-21 Wm-1 K-2, respectively. At second stage the optical characteristics of experimentally optimized sample were rigorously studied through the application of Material Studio software, while varying the doping ratio.

Construction of dual Z-scheme Ag3VO4-BiVO4/InVO4 photocatalysts using vanadium source from spent catalysts for contaminated water treatment and bacterial inactivation

Vanadate-based photocatalysts have recently attracted substantial attention owing to their outstanding photocatalytic activity for degrading organic pollutants and generating energy via photocatalytic processes. However, the relatively high price of vanadium has hindered the development of vanadate-based photocatalysts for various applications. Spent catalysts obtained from oil refineries typically contain a significant quantity of vanadium, making them valuable for recovery and utilization as precursors for the production of high-value-added photocatalysts. In this study, we transformed the V present in spent catalysts produced by the petrochemical industry into ternary vanadate-based photocatalysts [BiVO4/InVO4/Ag3VO4 (BVO/IVO/AVO, respectively)] designed for water remediation. The ternary composites revealed an enhanced photocatalytic capability, which was 1.42 and 5.1 times higher than those of the binary BVO/IVO and pristine AVO due to the facilitated charge separation. The ternary photocatalysts not only effectively treated wastewater containing various organic dyes, such as methylene blue (MB), rhodamine 6G (R6G), and brilliant green (BG), but also exhibited remarkable photocatalytic performance in the degradation of antibiotics, reduction of Cr(VI), and bacterial inactivation. This paper proposes a feasible route for recycling industrial waste as a source of vanadium to produce highly efficient vanadate-based photocatalysts.

Performance and applications of ZnO/pyrolusite composite particle electrode

In this research, we employed a synergistic three-dimensional (3D)-electrode technology in combination with a photocatalytic method to effectively treat wastewater containing chlorine derived from sulfonated phenolic resin (SMP). To modulate the band gap of single ZnO through semiconductor compounding, we successfully synthesized a ZnO/pyrolusite composite particle electrode on the surface of a pyrolusite particle electrode via a hydrothermal method. By incorporating MnO2 into pyrolusite, the ZnO band gap was modified, leading to a reduction in bandwidth of approximately 1.21 eV compared to pristine ZnO. Consequently, the light absorption range of the material was significantly broadened. Through the synergistic effect of photocatalysis, we achieved an impressive 96.45% removal rate of chemical oxygen demand (COD) in SMP wastewater, which effectively enhanced the photocatalytic performance of the material. Furthermore, our quenching experimental study confirmed the involvement of active chlorine species (ACl: Cl2, HClO, and ClO-), OH, h+, and O2- in the degradation process of SMP within the photocatalytic system constructed by the ZnO/pyrolusite composite particle electrode. The relative contributions were ranked as follows: ACl > h+ > ·OH > ·O2-.

Carboxymethyl cellulose/activated carbon/hydroxyapatite composite adsorbent for remediation of methylene blue from water media

In the present study, activated carbon (AC), activated carbon/hydroxyapatite (AC/HAp), and carboxymethyl cellulose/activated carbon/hydroxyapatite (CMC/AC/HAp) composite adsorbents were prepared to remediation of methylene blue (MB) from water media. The pyrolysis method used the Pine cone as a natural precursor to synthesize AC. FTIR, XRD, Raman, BET, TEM, and SEM-Dot mapping techniques were applied to characterize synthesized adsorbents. Experimental results demonstrated that the maximum removal efficiency of AC, AC/HAp, and CMC/AC/HAp adsorbents under optimum conditions of pH 8, adsorbent dose 1 g/L, contact time 60 min, initial concentration 10 mg/L, and temperature 25 °C was computed to be 98.75, 98.86, and 98.93 %, respectively. Kinetic and equilibrium data were well-fitted with pseudo-second-order and Langmuir models, respectively. The maximum monolayer adsorption capacity of AC, AC/HAp, and CMC/AC/HAp was determined to be 40, 44.248, and 43.86 mg/g, respectively. FTIR results showed that hydrogen bonding and electrostatic interactions are the main mechanisms of the adsorption process. Results of the thermodynamic study showed that the adsorption process is spontaneous and exothermic. Finally, AC, AC/HAp, and CMC/AC/HAp composite adsorbents can be used as promising adsorbents for the remediation of MB from wastewater.

Treating waste with waste: adsorption behavior and mechanism of phosphate in water by modified phosphogypsum biochar

The use of green methods to treat industrial waste and waste reuse has become a key environmental issue. In order to achieve this goal, this study treated waste phosphogypsum (PG) and produced modified PG biochar to adsorb and remove phosphorus from PG leachate, so that the PG pollution problem was controlled. In this study, PG was modified with sodium carbonate (Na2CO3) to prepare a modified PG biochar that was used for the removal of phosphorus-containing wastewater. An X-ray diffraction (XRD) analysis of the modified PG revealed that the main component was calcium carbonate (CaCO3), and a suitable amount of modified PG could load calcium oxide (CaO) onto the biochar and improve its physical properties. The experimental results showed that the modified PG biochar had a maximum phosphorus adsorption capacity of 132 mg/g. A further investigation of the mechanism of adsorption revealed the importance of electrostatic attraction and chemical precipitation, and it was found that the CaO in the modified PG biochar could effectively facilitate the conversion of phosphate to hydroxylapatite (Ca5(PO4)3OH) in water. The phosphorus removal rate from leachate obtained from a landfill containing PG was 99.38% for a specific dose of the modified PG biochar. In this study, a PG pollution control technology was developed to realize the goal of replacing waste with waste.

Fabrication of MoS2 restrained magnetic chitosan polysaccharide composite for the photocatalytic degradation of organic dyes

Chitosan (CS) polysaccharide is expected to exhibit greater ionic conductivity, which can be attributed to its increased amino group content when it is blended with different semiconducting materials. Herein, the work used this conducting ability of chitosan and prepared a heterogeneous MoS2-induced magnetic chitosan (MF@CS) composite via the co-precipitation method, which was used to scrutinize the catalytic performance with Methylene Blue (MB) and Malachite Green (MG) dyes by visible light irradiation. The saturation magnetization value of the MF@CS composite is found to be 7.8 emu/g, which is less when compared to that of pristine Fe3O4 (55.7 emu/g) particles. The bandgap of the MF@CS composite is ∼ 2.17eV, which exceeds the bandgap (Eg) of bare MoS2 of 1.80 eV. The maximum color removal of 96.3 % and 93.4 % for MB and MG dyestuffs is recognized in the exposure of the visible spectrum, respectively. At a starting dye dosage of 30 mg/L, 0.1 g/L of MF@CS, a pH level of 8-11, and 70 min of contact with direct light. The photocatalyst provides extremely good durability for a maximum of five phases. Hence, the MF@CS matrix is a viable and appropriate substance for the efficient treatment of effluents containing dye molecules.

Constructing the synergistic effects of chitosan and ionic liquid on SPEEK polymer for efficient adsorption of crystal violet dye

In the study, a novel chitosan biopolymer and 1-ethyl-3-methylimidazolium tetrafluoroborate ionic liquid (IL)-incorporated sulfonated poly (ether ether ketone) (SPEEK) composite (Ch-IL@SPEEK) was prepared for adsorption of cationic crystal violet (CV) dye. The proposed composite was well characterized by several techniques. CV adsorption performance was examined via batch studies by varying various variables involving adsorbent dosage, contact time pH and temperature. The isotherm results were demonstrated the adsorption characters of the processes were Langmuirian. The maximum adsorption capacity was determined as 77.66 mg g-1 for the composite which was significantly higher than SPEEK (qmax = 45.36 mg g-1). The determined equilibrium time of the operated system was 360 min and the kinetic model was assessed as Elovich. At low pHs the protonated surface groups repelled the positively charged CV and the adsorption rate increased with increasing pH. The process is spontaneous and favorable as it proceeds via endothermic interactions. Furthermore, even at the end of 5 successful adsorption cycles, 77.86 % CV removal was obtained. Remarkable efficiencies were also achieved in the removal performance of different organic pollutants. Based on the reported results, Ch-IL@SPEEK composite were exhibited as an impressive adsorbent material for adsorption processes.

Protective effects of sodium humate and its zinc and selenium chelate on the oxidative stress, inflammatory, and intestinal barrier damage of Salmonella Typhimurium-challenged broiler chickens

The objective of this study was to investigate the protective effects and mechanisms of dietary administration of sodium humate (HNa) and its zinc and selenium chelate (Zn/Se-HNa) in mitigating Salmonella Typhimurium (S. Typhi) induced intestinal injury in broiler chickens. Following the gavage of 109 CFU S. Typhi to 240 broilers from 21-d to 23-d aged, various growth performance parameters such as body weight (BW), average daily gain (ADG), average daily feed intake (ADFI), and feed ratio (FCR) were measured before and after infection. Intestinal morphology was assessed to determine the villus height, crypt depth, and chorionic cryptologic ratio. To evaluate intestinal barrier integrity, levels of serum diamine oxidase (DAO), D-lactic acid, tight junction proteins, and the related genes were measured in each group of broilers. An analysis was conducted on inflammatory-related cytokines, oxidase activity, and Nuclear Factor Kappa B (NF-κB) and Nuclear factor erythroid2-related factor 2 (Nrf2) pathway-related proteins and mRNA expression. The results revealed a significant decrease in BW, ADG, and FCR in S. typhi-infected broilers. HNa tended to increase FCR (P = 0.056) while the supplementation of Zn/Se-HNa significantly restored BW and ADG (P < 0.05). HNa and Zn/Se-HNa exhibit favorable and comparable effects in enhancing the levels of serum DAO, D-lactate, and mRNA and protein expression of jejunum and ileal tight junction. In comparison to HNa, Zn/Se-HNa demonstrates a greater reduction in S. Typhi shedding in feces, as well as superior efficacy in enhancing the intestinal morphology, increasing serum catalase (CAT) activity, inhibiting pro-inflammatory cytokines, and suppressing the activation of the NF-κB pathway. Collectively, Zn/Se-HNa was a more effective treatment than HNa to alleviate adverse impact of S. Typhi infection in broiler chickens.

Perspectives on cultivation and harvesting technologies of microalgae, towards environmental sustainability and life cycle analysis

The development of algae is seen as a potential and ecologically sound approach to address the increasing demands in multiple sectors. However, successful implementation of processes is highly dependent on effective growing and harvesting methods. The present study provides a complete examination of contemporary techniques employed in the production and harvesting of algae, with a particular emphasis on their sustainability. The review begins by examining several culture strategies, encompassing open ponds, closed photobioreactors, and raceway ponds. The analysis of each method is conducted in a systematic manner, with a particular focus on highlighting their advantages, limitations, and potential for expansion. This approach ensures that the conversation is in line with the objectives of sustainability. Moreover, this study explores essential elements of algae harvesting, including the processes of cell separation, dewatering, and biomass extraction. Traditional methods such as centrifugation, filtration, and sedimentation are examined in conjunction with novel, environmentally concerned strategies including flocculation, electro-coagulation, and membrane filtration. It evaluates the impacts on the environment that are caused by the cultivation process, including the usage of water and land, the use of energy, the production of carbon dioxide, and the runoff of nutrients. Furthermore, this study presents a thorough examination of the current body of research pertaining to Life Cycle Analysis (LCA) studies, presenting a perspective that emphasizes sustainability in the context of algae harvesting systems. In conclusion, the analysis ends up with an examination ahead at potential areas for future study in the cultivation and harvesting of algae. This review is an essential guide for scientists, policymakers, and industry experts associated with the advancement and implementation of algae-based technologies.

Pirarucu hydroxyapatite applied to ternary competitive adsorption of synthetic basic dyes as contaminants of emerging concern: kinetic, equilibrium, and ANN studies

This study investigated the single and multicomponent adsorption of three emerging pollutants, the basic dyes Rhodamine 6G (R6G), Auramine-O (AO), and Brilliant Green (BG) by using hydroxyapatite synthesized from Pirarucu scales as adsorbent (HAP). The adsorption process was studied using seven different systems: AO-single, R6G-single, BG-single, R6G + AO, BG + AO, BG + R6G, and R6G + AO + BG. For kinetics, the initial concentration of each adsorbate per system was 50 mg/L, the results showed that the singular adsorption of these dyes was best-represented by the pseudo-second-order model (qAO = 62.54 mg/g, qR6G = 7.91 mg/g, qBG = 62.40 mg/g), however, the multicomponent adsorption was well-fitted by a pseudo-first-order model (ternary system: qAO = 56.21 mg/g, qR6G = 14.95 mg/g, qBG = 60.62 mg/g). For equilibrium, the initial concentration of each adsorbate per system was 10-300 mg/L, and the single adsorption systems were best represented by the Langmuir model. Nonetheless, the results displayed in the multicomponent mixture showed the presence of inflection points of AO and R6G whenever BG was present in solution with C0 > 150 mg/L, thus indicating that BG has greater affinity with HAP. The presence of inflection points in the curves represented a limitation for applying traditional equilibrium models, thus, an artificial neural network (ANN) was applied to non-linear curve fit this process and satisfactorily predicted the kinetics and equilibrium data. Finally, the analysis of thermodynamics for the ternary mixture revealed that the adsorption process is spontaneous (ΔG < 0), endothermic (ΔH > 0), and increases to a disorganized state as the temperature rises (ΔS > 0).

Powdered silk: A promising biopolymer for the treatment of dye contaminated water

Discharge of textile dye effluents into water bodies is creating stress to aquatic life and contaminating water resources. In this study, a new biopolymer adsorbent silk fibroin (SF) was prepared from Bombyx mori silk fibroin (SF) and used for removal of Solochrome Black-T (SB-T) from water. This innovative adsorbent exhibits an exceptional adsorption capacity of 20.08 mg/g, achieving a removal efficiency of approximately 98.6 % within 60 min. Notably, the powdered SF adsorbent demonstrates rapid kinetics, surpassing the performance of previously reported similar adsorbents in adsorption capacity and reaction speed. The molecular weight and particle diameter of the material were observed to be > 1.243 kDa and 3 μm, respectively. The experimental investigations were performed on different parameters, viz., adsorbent dosage, contact time, repeatability, and desorption-adsorption study. The experimental data well fit for the Langmuir model (R2 = 0.937, qmax = 20.08 mg/g) and the pseudo-second-order kinetics (R2 = 0.921 and qe = 1.496 mg/g). Compared to the adsorbents reported in the literature, the newly prepared SF showed high adsorption capacity and faster kinetics to address real-life situations. The novelty of this work extends beyond its remarkable adsorption capabilities. The SF adsorbent offers a cost-effective, sustainable solution and regenerable adsorption material with minimal negative environmental impacts. This regenerability, with its versatility and broad applicability, positions powdered SF fibroin as a transformative technology in water treatment and environmental protection.

Novel multifunctional environmentally friendly degradable zeolitic imidazolate frameworks@poly (γ-glutamic acid) hydrogel with efficient dye adsorption function

Recently, metal-organic frameworks (MOFs) have been widely developed due to the rich porosity, excellent framework structure and multifunctional nature. Meanwhile, a series of MOFs crystals and MOF-based composites have been emerged. However, the widespread applications of MOFs are hindered by challenges such as rigidity, fragility, solution instability, and processing difficulties. In this study, we addressed these limitations by employing an in-situ green growth approach to prepare a zeolitic imidazolate frameworks-8@poly (γ-glutamic acid) hydrogel (ZIF-8@γ-PGA) with hierarchical structures. This innovative method effectively resolves the inherent issues associated with MOFs. Furthermore, the ZIF-8@γ-PGA hydrogel is utilized for dye adsorption, demonstrating an impressive maximum adsorption capacity of 1130 ± 1 mg/g for methylene blue (MB). The adsorption behavior exhibits an excellent agreement with both the kinetic model and isotherm. Meanwhile, because the adsorbent raw materials are all green non-toxic materials, multiple applications of materials can also be realized. Significantly, the results of antibacterial experiments showed that the ZIF-8@γ-PGA hydrogel after in-situ growth of ZIF-8 had better antibacterial properties. Thus, the ZIF-8@γ-PGA hydrogel has great potential for development in wound dressings, sustained drug owing to its biocompatibility and antibacterial activity.

Tetracycline decontamination from aqueous media using nanocomposite adsorbent based on starch-containing magnetic montmorillonite modified by ZIF-67

In the present study, starch/zeolitic imidazole framework-67 (ZIF-67) modified magnetic montmorillonite nanocomposite adsorbent to remove tetracycline (TC) as an emerging antibiotic-based contaminant from aqueous media. The surface properties of the adsorbents were investigated using FTIR, XRD, SEM, EDX-Map, XPS, TEM, BET, and VSM analysis. The specific surface area of MMT, St/MMT-MnFe2O4, and St/MMT-MnFe2O4-ZIF-67 magnetic nanocomposite samples were found to be 15.63, 20.54, and 588.41 m2/g, respectively. The influence of pH, adsorbent amount, initial TC concentration, temperature, contact time, and coexisting ions on TC elimination was explored in a batch adsorption system. The kinetic and equilibrium data were well matched with the pseudo-second-order and Langmuir isotherm models, respectively. The maximum monolayer adsorption capacities of TC were obtained to be 40.24, 66.1, and 135.2 mg/g by MMT, St/MMT-MnFe2O4, and St/MMT-MnFe2O4-ZIF-67 magnetic nanocomposite adsorbents, respectively. Also, thermodynamic studies illustrated that the TC adsorption process is exothermic and spontaneous. Furthermore, the magnetic nanocomposite adsorbent St/MMT-MnFe2O4-ZIF-67 showed good reusability and could be recycled for up to five cycles. This excellent adsorption performance, coupled with the facile separation of the magnetic nanocomposite, gave St/MMT-MnFe2O4-ZIF-67 a high potential for TC removal from aqueous media.

Facile green synthesis route for new ecofriendly photo catalyst for degradation acid red 8 dye and nitrogen recovery

This study novelty is that new photo catalyst prepared from sustainability low cost precursors. Dark red color hydrogel composites have been easily prepared from gelatin biopolymer using a simple sol-gel method. Gelatin doped by cobalt chloride, and silver nanoparticles (SNPs) in the presence of traces amount of sodium dodecyl sulfate surfactant and calcium chloride. Water-insoluble Gelatin composites are thermally stable photocatalysts for the degradation of toxic anionic acid red 8 dye. Promising photodynamic activity confirmed by fluorescence emission at λmax 650 nm. Optical absorption in Vis. light enhanced photo catalytic activity. Silver nanoparticles enhanced crystallinity, and improved optical properties and porosity. Dopants by CoCl2 and silver nanoparticles increased band gap of gelatin composites from (1.82 to 1.95) indicating interfacial charge separation. Low band gaps improved photo catalytic activity. Optical band gaps (Eg) lower than 2.0 eV indicates high catalytic activity in the photo degradation acid red 8 dye using Vis. light, wavelength 650 nm. Percent removal efficiency (%Re) of the dye at 500 ppm initial concentration, pH 1, contact time 30 min., and 0.20 g L-1 dose photo catalyst reached 95%. pH not affects removal efficiency. So, gelatin composites removed AR8 dye by photodegradation mechanism rather than adsorption due to photodynamic activity. Kinetics of photodegradation followed pseudo first order kinetic with rate constant k1 5.13 × 10-2 min.-1 Good electrical conductivity and magnetic properties (effective magnetic moment (µeff 4.11 B.M) improved dye degradation into simple inorganic species. Nutrients NH4+, and NO3- degradation products recovered by using alumina silicate clay via a cation exchange mechanism.

Recent advances in cellulose-based sustainable materials for wastewater treatment: An overview

Water pollution presents a significant challenge, impacting ecosystems and human health. The necessity for solutions to address water pollution arises from the critical need to preserve and protect the quality of water resources. Effective solutions are crucial to safeguarding ecosystems, human health, and ensuring sustainable access to clean water for current and future generations. Generally, cellulose and its derivatives are considered potential substrates for wastewater treatment. The various cellulose processing methods including acid, alkali, organic & inorganic components treatment, chemical treatment and spinning methods are highlighted. Additionally, we reviewed effective use of the cellulose derivatives (CD), including cellulose nanocrystals (CNCs), cellulose nano-fibrils (CNFs), CNPs, and bacterial nano-cellulose (BNC) on waste water (WW) treatment. The various cellulose processing methods, including spinning, mechanical, chemical, and biological approaches are also highlighted. Additionally, cellulose-based materials, including adsorbents, membranes and hydrogels are critically discussed. The review also highlighted the mechanism of adsorption, kinetics, thermodynamics, and sorption isotherm studies of adsorbents. The review concluded that the cellulose-derived materials are effective substrates for removing heavy metals, dyes, pathogenic microorganisms, and other pollutants from WW. Similarly, cellulose based materials are used for flocculants and water filtration membranes. Cellulose composites are widely used in the separation of oil and water emulsions as well as in removing dyes from wastewater. Cellulose's natural hydrophilicity makes it easier for it to interact with water molecules, making it appropriate for use in water treatment processes. Furthermore, the materials derived from cellulose have wider application in WW treatment due to their inexhaustible sources, low energy consumption, cost-effectiveness, sustainability, and renewable nature.

MOF-derived Co-Ni layered double hydroxides/polyethyleneimine modified chitosan micro-nanoreactor for high-efficiency capture of uranium from seawater

The preparation of powder adsorbent into microsphere adsorbent is one of the effective methods for the industrialization of uranium extraction from seawater. Herein, a MOF-derived Co-Ni layered double hydroxides/polyethyleneimine modified chitosan micro-nanoreactor (DNPM) was prepared by a simple method in this work. The microstructure and chemical structure of DNPM were comprehensively characterized. The pH value, adsorption time, initial solution concentration, temperature, competitive ions, regeneration performance, and bed column heights were investigated for the adsorption performance of DNPM by batch adsorption and fixed-bed column continuous adsorption experiments. When the contact time was 8 h, the initial concentration was 150 mg/L, and the pH value was 6, the adsorption capacity of DNPM was 334.67 mg/g. The uranium adsorption by DNPM fits with the pseudo-second-order kinetic and Langmuir models, which was a spontaneous and endothermic process. In addition, DNPM has good adsorption selectivity and reusability. The fixed-bed column continuous adsorption experiment shows that the adsorption capacity increased with the increase of bed column height. The adsorption mechanism can be attributed to coordination chelation and electrostatic interaction. In general, this work provides an effective strategy for developing environmentally friendly uranium adsorbent that can be industrially used.

A novel CoMoO4 enwrapped ZIF-8 nanocomposite with enhanced visible light photocatalytic activity

A hybrid nano catalyst, CoMoO4 anchored zeolitic imidazolate framework-8 (ZIF-8) has been synthesized by simplest in-situ chemical method. The characterization results showed that the CoMoO4@ZIF-8 composites had a crystalline structure with a uniform distribution of the Cobalt molybdate particles on the ZIF-8 surface. The FTIR spectra revealed the presence of characteristic peaks for both ZIF-8 and CoMoO4, indicating the successful incorporation of the metal molybdate into the ZIF-8 framework. The SEM-EDS analysis showed that the CoMoO4 nanoparticles (NPs) have been evenly distributed on the ZIF-8 surface. In HRTEM, some rod-like CoMoO4 is observed on the surface of the ZIF-8 material, which is stacked in a disorderly manner and a porous channel structure is formed. The photocatalytic activity of the CoMoO4@ZIF-8 has been evaluated using the degradation of methylene blue (MB) and antibiotic Ciprofloxacin (CIP) under visible light. The optimal photocatalytic activity was achieved with the CoMoO4@ZIF-8 composite, which showed a degradation efficiency of 100% under visible light after 40 min of irradiation. In conclusion, the CoMoO4@ZIF-8 composites showed enhanced photocatalytic activity under visible light, and it exhibited the best performance compared with pure CoMoO4 and ZIF-8.

Wastewater purification from Rhodamine B and Gemifeloxacine by graphene oxide/pectin/ferrite nanocomposite: A novel molecular dynamics simulation for experimental contaminants removing

In this study, the synthesized nanocomposite was evaluated novel graphene oxide/pectin/ferrite (GOPF) adsorbent to the adsorption of Rhodamine B (RhB) and Gemifloxacin (GEM) from wastewater. Theoretical studies were carried out using quantum simulation via the Forcite module in Material Studio 2017. The simulation results demonstrated RhB and GEM adsorption over other dyes and drugs. The synthesized nanocomposite was identified by BET, TGA, FT-IR, FE-SEM, XRD, VSM, and EDS. The nanocomposite's ability to effectively take RhB and GEM from an aqueous solution was checked by performing a series of experiments based on the effect of adsorbent dose, initial condensation, contact time, pH, and temperature. The nanocomposite kinetics follow a PSO. The Freundlich isotherm model was applied for maximum adsorption capacity of GEM (124.37 mg/g) and RhB (86.60 mg/g) on GOPF nanocomposite. According to the antibacterial activity test, the synthesized nanocomposite can kill bacteria 5 mm in diameter. Also, the anti-cancer test of nanocomposite was done with 75% viability in high concentrations of nanocomposite. Thus, GOPF application results are not only suitable for dyes but only satisfying for drugs. PRACTITIONER POINTS: GOPF nanocomposite was fabricated for adsorption dye and drug and characterized. The effect of different process parameters, pH, catalyst dosage, contact time, and temperature effect was surveyed. The MD simulation were investigated to adsorb various dyes and drugs. The equilibrium isotherm and adsorption kinetic follow from Freundlich and pseudo-second-order kinetics; GOPF nanocomposite was used for about six cycles. The antibacterial activity and anticancer test of GOPF nanocomposite were investigated by satisfying results.

Adsorption-photocatalytic degradation abilities of γ-irradiated chitosan-ZnO-AgNP composite for organic dye removal and antibacterial activity

We synthesized a γ-irradiated chitosan-ZnO-AgNPs (ICZA) composite by using a simple hydrogels method. We evaluated its adsorption/photocatalytic degradation abilities for the removal of an organic dye and its antibacterial activity. The XRD, SEM, TEM, EDS, and FTIR techniques were used to characterize the obtained samples. Based on the adsorption and degradation of methylene blue (MB) in the dark and under UV light irradiation, the adsorption and the photocatalytic activity of the as-obtained samples were evaluated. The optimum conditions for synthesizing the composite were as follows: contact time of 210 min, a dosage of 2 g/L, MB concentration of 40 mg/L, and a solution pH of 8.0. The ICZA had a high adsorption capacity, which was suitable for removing MB from the aqueous solutions; it showed a maximum adsorption capacity (qm) of 92.59 mg/g. The fit of the adsorption isotherms with the Langmuir model was satisfactory. The photocatalytic degradation ability of the composite was also better than that of other catalysts in the presence of UV light, with an apparent rate constant (kapp) of 3.08 × 10-2. The synthesized ICZA also showed good antibacterial activity against Staphylococcus aureus, with a minimum inhibitory concentration (MIC) and a minimum bactericidal concentration (MBC) of 12.5 g/mL and 50 g/mL under light-incubation and dark-incubation conditions. Finally, we discussed the hypothesized mechanism of the adsorption/photocatalytic activity and antibacterial activity of the ICZA composite in this study.

Significant photocatalytic decomposition of malachite green dye in aqueous solutions utilizing facilely synthesized barium titanate nanoparticles

The release of malachite green dye into water sources has detrimental effects on the liver, kidneys, and respiratory system. Additionally, this dye can impede photosynthesis and disrupt the growth and development of plants. As a result, in this study, barium titanate nanoparticles (BaTiO₃) were facilely synthesized using the Pechini sol-gel method at 600 °C (abbreviated as EA600) and 800 °C (abbreviated as EA800) for the efficient removal of malachite green dye from aqueous media. The Pechini sol-gel method plays a crucial role in the production of barium titanate nanoparticles due to its simplicity and ability to precisely control the crystallite size. The synthesized barium titanate nanoparticles were characterized by several instruments, such as X-ray diffraction (XRD), high-resolution transmission electron microscopy (HR-TEM), Fourier transform infrared spectroscopy, and a diffuse reflectance spectrophotometer. The XRD analysis confirmed that the mean crystallite size of the EA600 and EA800 samples is 14.83 and 22.27 nm, respectively. Furthermore, the HR-TEM images confirmed that the EA600 and EA800 samples exhibit irregular and polyhedral structures, with mean diameters of 45.19 and 72.83 nm, respectively. Additionally, the synthesized barium titanate nanoparticles were utilized as catalysts for the effective photocatalytic decomposition of malachite green dye in aqueous media. About 99.27 and 93.94% of 100 mL of 25 mg/L malachite green dye solution were decomposed using 0.05 g of the EA600 and EA800 nanoparticles within 80 min, respectively. The effectiveness of synthesized BaTiO₃ nanoparticles as catalysts stems from their unique characteristics, including small crystallite sizes, a low rate of hole/electron recombination owing to ferroelectric properties, high chemical stability, and the ability to be regenerated and reused multiple times without any loss in efficiency.

Controlled Synthesis and Visible-Light-Driven Photocatalytic Activity of BiOBr Particles for Ultrafast Degradation of Pollutants

For the purpose of regulating the visible-light-driven photocatalytic properties of photocatalysts, we selected BiOBr as the research target and various routes were used. Herein, via the use of a hydrothermal method with various solvents, BiOBr particles with controllable morphology and photocatalytic activities are obtained. In particular, through changing the volume ratio of ethylene glycol (EG) to ethanol (EtOH), BiOBr compounds possess microspheres, in which samples synthesized by using EG:EtOH = 1:2 have the highest photocatalytic activity, and can completely decompose RhB under visible light irradiation within 14 min. Furthermore, we also used different volume ratios of EG and H₂O reaction solvents to prepare BiOBr particles so as to further improve its pollutant removal ability. When the volume ratio of EG to H₂O is 1:1, the synthesized BiOBr particles have the best photocatalytic activity, and RhB can be degraded in only 10 min upon visible light irradiation. Aside from the reaction solvent, the impact of sintering temperature on the photocatalytic properties of BiOBr particles is also explored, where its pollutant removal capacities are restrained due to the reduced specific surface area. Additionally, the visible-light-triggered photocatalytic mechanism of BiOBr particles is determined by h⁺, ·OH and ·O^2- active species.

Ultrasound-Assisted Synthesis of a ZnO/BiVO4 S-Scheme Heterojunction Photocatalyst for Degradation of the Reactive Red 141 Dye and Oxytetracycline Antibiotic

The preparation of novel sunlight active photocatalysts for complete removal of pollutants from aqueous solutions is a vital research topic in environmental protection. The present work reports the synthesis of a ZnO/BiVO4 S-scheme heterojunction photocatalyst for degradation of the reactive red dye and oxytetracycline antibiotic in wastewater. ZnO and BiVO4 were first fabricated by a hydrothermal technique, and then, the ZnO/BiVO4 heterostructure was synthesized using an ultrasonic route. An increase of the surface area, compared to that of ZnO, was found in ZnO/BiVO4. The enhancement of charge separation efficiency at the interface was obtained so that a remarkable enhancement of the photocatalytic performance was detected in the prepared heterojunction photocatalyst. Complete detoxification of harmful pollutants was achieved by using the economical solar energy. The removal of the pollutants follows the first-order reaction with the highest rate constant of 0.107 min-1. The stability of the prepared photocatalyst was detected after five cycles of use. The ZnO/BiVO4 S-scheme heterostructure photocatalyst still provides high photoactivity even after five times of use. Hydroxyl radicals play an important role in the removal of the pollutant. This work demonstrates a new route to create the step-scheme heterojunction with high photoactivity for complete removal of the toxic dye and antibiotic in the environment.

Heterostructured Photocatalysts Associating ZnO Nanorods and Ag-In-Zn-S Quantum Dots for the Visible Light-Driven Photocatalytic Degradation of the Acid Orange 7 Dye

Heterostructured photocatalysts associating ZnO nanorods (NRs) sensitized by quaternary Ag-In-Zn-S (AIZS) quantum dots (QDs) were prepared by depositing AIZS QDs at the surface of ZnO NRs followed by thermal treatment at 300 °C. The ZnO/AIZS catalysts were characterized by X-ray diffraction, electron microscopy, UV-vis diffuse spectroscopy and by photoelectrochemical measurements. Their photocatalytic activity was evaluated for the bleaching of the Acid Orange 7 (AO7) dye under visible light irradiation. Results show that the association of ZnO NRs with 10 wt% AIZS QDs affords the photocatalyst the highest activity due to the enhanced visible light absorption combined with the improved charge separation. The ZnO/AIZS(10) photocatalyst degrades 98% AO7 in 90 min under visible light illumination, while ZnO NRs can only decompose 11% of the dye. The ZnO/AIZS(10) photocatalyst was also found to be stable and can be reused up to eight times without significant alteration of its activity. This work demonstrates the high potential of AIZS QDs for the development of visible light active photocatalysts.

Photocatalytic degradation effect of CdSe nanoparticles for textile wastewater effluents at low cost and proves to be efficient method

Semiconductor nanoparticles and nanocrystals have a great impact due to its contribution in the diverse fields including electronics, solar energy, biological imaging, and photonics. Among these semiconductor nanoparticles, cadmium selenide of II-VI group binary semiconductor nanoparticles were synthesized using solvothermal process for the different reaction temperatures. The XRD pattern of the synthesized samples confirms the crystalline nature of the samples and showed increase in its crystallite size with rise in temperature. The morphology of the samples was analysed with TEM images and found that the nanoparticles synthesized at different temperatures were varied in size and shape indicating the increase in the size of the particles with the raise in temperature. The optical properties of the samples pointed out that they exhibit a blue shift owing to quantum confinement. Photocatalytic activity was carried out for the synthesized samples under visible light radiation using methylene blue (MB) as a model pollutant and it proved to be a good photocatalyst achieving the efficiency of 75% which is promising for future application with good optimization. The efficiency could be increased when these semiconductor CdSe nanoparticles are doped with metal particles due to an increase in the absorption edge wavelength and a decrease in bandgap energy were reported in detail.

Surface conjugation of titanium dioxide nanoparticles on nano-graphene oxide enhances photocatalytic degradation of azo dyes under sunlight

Here, conjugate of nano-graphene oxide (GO) and titanium dioxide nanoparticle (nTiO₂) was proposed for the photocatalytic degradation of two toxic azo dyes, Congo red (CR) and Methylene blue (MB), under sunlight irradiation. Furthermore, the optimized weight ratio between GO and nTiO₂ of 1:5 demonstrated the highest degradation efficiency. The nanoconjugate induced 85% degradation of 40 ppm of CR in 60 min and a complete degradation within 70 min, while it degraded more than 90% of 20 ppm of MB in 80 min. The photocatalyst can be reused for five cycles of photocatalysis. Thus, the photocatalytic potential of GO/nTiO₂ under visible light may be used as a very suitable and cost-effective photocatalyst industrially for the removal of toxic dyes from water.

Assembly and Photocatalytic Degradation Activity of Spherical ZnO/CdSe Heterostructures on Flexible Carbon Cloth Substrates

With the increasing water pollution, traditional treatments cannot sufficiently remove pollutants, thereby prompting the development of photocatalysts. In this study, ZnO–carbon cloth (CC) and spherical ZnO/CdSe–CC heterostructures with different CdSe loadings were synthesized using an ultrasonic-hydrothermal method on flexible CC. Z20CdSe–CC (ZnO with 20 mg CdSe loaded on CC) exhibited the best visible-light-responsive photocatalytic performance, with approximately 83.5% methylene blue reduced in 180 min. In addition, the degradation efficiency of Z20CdSe–CC was maintained at 70.9% after three cycles in relation to that of the ZnO powder. The synergistic effect of CdSe and CC not only effectively widened the light absorption range of ZnO/CdSe–CC but also further promoted the effective transfer of carriers and realized an efficient photocatalytic degradation process. Therefore, the ZnO/CdSe–CC photocatalytic material with CC as the flexible substrate exhibited high photocatalytic activity and stability in environmental remediation. This provides a design idea for the development of an efficient and flexible photocatalytic material in line with the concept of green chemistry.

Sonochemical Synthesis, Characterization and Optical Properties of Tb-Doped CdSe Nanoparticles: Synergistic Effect between Photocatalysis and Sonocatalysis

In this study, Tb-doped CdSe nanoparticles with variable Tb³⁺ content were synthesized by a simple sonochemical technique. The synthesized nanoparticles were characterized by X-ray photoelectron spectroscopy (XPS), scanning electron microscopy (SEM), and powder X-ray diffraction (XRD). The sono-photocatalytic activities of the as-prepared specimens were assessed for the degradation of Reactive Black 5. The experimental results show that the sono-photocatalytic process (85.25%) produced a higher degradation percentage than the individual sono- (22%) and photocatalytic degradation (8%) processes for an initial dye concentration and Tb-doped CdSe dosage of 20 mg/L and 1 g/L, respectively. Response surface methodology (RSM) was utilized to assess model and optimize the impacts of the operational parameters, namely, the Tb³⁺ content, initial dye concentration, catalyst dosage, and time. The addition of benzoquinone results in remarkably inhibited degradation and the addition of ammonium oxalate reduced the removal percentage to 24%. Superoxide radicals and photogenerated holes were detected as the main oxidative species.

Transition metal selenides and diselenides: Hydrothermal fabrication, investigation of morphology, particle size and and their applications in photocatalyst

This review investigates hydrothermal synthesis of metal selenides and diselenides. Briefly, structures, applications and formation mechanisms are studied. The strategies for developing metal selenides, including NiSe, NiSe₂, Ni₃Se₂, CdSe, FeSe₂, MnSe₂, CoSe, CuSe, Cu_1.8Se, CuSe₂, Cu₃Se₂ and ZnSe are discussed. More of 50 hydrothermal methods used for the synthesis of metal selenides are discussed. As well as the investigation of the photocatalytic activities of these metal selenides are followed by different synthesis methods and strategies employed for the synthesis of them.