Enhanced photocatalytic performance of ZnSnO3/rGO nanocomposite

ZnSnO3-derived ZnSnO3/ZIF-8 composites with enhanced adsorption and photocatalytic activity in RhB degradation and CO2 reduction

This study aims to increase the photoactivity of ZnSnO3 by modifying it with zeolitic imidazolate framework-8 (ZIF-8). The composite catalyst was prepared by a straightforward hydrothermal method using ZnSnO3 as the zinc source. The in-situ generated ZnSnO3/ZIF-8 composite exhibits a strong interaction between ZnSnO3 and ZIF-8, which benefits electron transfer. Band structure analysis shows that ZIF-8 has a higher conduction band and a lower valence band than ZnSnO3, and cannot form a typical heterojunction. However, defects in ZIF-8 may act as electron traps, accepting electrons from the conduction band of ZnSnO3. This atypical heterojunction results in the spatial separation of charge carriers within the composite. The transient photocurrent response, electrochemical impedance spectroscopy, and photoluminescence analysis confirmed this hypothesis. Meanwhile, ZIF-8 also plays a role in adsorbing dyes and concentrating reactants due to its extremely high specific surface area. Therefore, the ZnSnO3/ZIF-8 composite exhibits significantly improved photocatalytic performance in Rhodamine B degradation. The degradation rate of the best sample was 10.4 times that of ZnSnO3. Active species capture experiments showed that holes and superoxide radicals were the main active species. Additionally, the ZnSnO3/ZIF-8 composite showed enhanced photocatalytic activity in CO2 reduction. This study may show new insights into the design of efficient photocatalytic materials using metal-organic framework materials.

Development of novel reduced graphene oxide/metalloporphyrin nanocomposite with photocatalytic and antimicrobial activity for potential wastewater treatment and medical applications

This research investigates a novel nanocomposite material composed of reduced graphene oxide (rGO) and nickel-5,15-bisdodecylporphyrin (Ni-BDP) nanoparticles for the effective removal of methyl orange (MO), a harmful synthetic dye, from water. The structure and composition of the synthesized rGO/Ni-BDP nanocomposite were characterized using high-resolution transmission electron microscopy (HR-TEM), Raman spectroscopy, nuclear magnetic resonance (NMR) spectroscopy, mass spectrometry, and ultraviolet-visible (UV-Vis) spectroscopy. The study demonstrates the material's efficacy as both a catalyst and adsorbent for MO removal. Optimal performance was observed at pH 3.0, where the positively charged nanocomposite surface facilitated strong interactions with negatively charged MO molecules, leading to enhanced photocatalytic activity. Under these conditions, 0.01 g of the nanocomposite achieved an impressive 86.2% MO removal efficiency. Furthermore, the study explored the reusability of the rGO/Ni-BDP nanocomposite in repeated cycles of photocatalytic MO degradation under visible light irradiation. While exhibiting some decrease in efficiency over five cycles, the nanocomposite maintained a respectable degradation rate even after multiple uses. Finally, the antimicrobial properties of the nanocomposite were evaluated against both Gram-negative (Escherichia coli) and Gram-positive (Staphylococcus aureus) bacteria exhibiting a zone of inhibition measuring 23 mm and 26, respectively. The minimum inhibitory concentration (MIC) values of 2.50 µg/ml and 1.25 µg/ml for Escherichia coli and Staphylococcus aureus, respectively. The results revealed significant antibacterial activity, demonstrating the broad-spectrum efficacy of the rGO/Ni-BDP nanocomposite. This research underscores the potential of the rGO/Ni-BDP nanocomposite as a versatile material for environmental remediation and antibacterial applications.

Enhanced piezocatalytic RhB degradation with ZnSnO3 Nanocube-modified Bi4Ti3O12 composite catalyst by harnessing ultrasonic energy

With the increasing demand for effective methods to address environmental pollution, piezocatalysis has emerged as a promising approach for pollutant degradation under mechanical energy. However, the development of highly efficient piezocatalytic materials remains a challenge. This study aimed to increase the piezocatalytic activity of bismuth titanate (Bi4Ti3O12) by modifying it with zinc stannate (ZnSnO3) nanocubes. The composite catalysts were synthesized using a straightforward deposition and calcination process. The calcination process ensured the tight adhesion of ZnSnO3 nanocubes to the Bi4Ti3O12 surface, while facilitating strong interactions between ZnSnO3 and Bi4Ti3O12, which enhanced electron transfer and heterojunction structure formation. Band structure analysis indicated that Bi4Ti3O12 has higher conduction band and valence band potentials than ZnSnO3, forming a type-II heterojunction. Bi4Ti3O12 possesses a higher Fermi level than ZnSnO3, resulting in interfacial electron drift and formation of a built-in electric field, which further promotes the directional transfer and separation efficiency of charge carriers within the composite catalyst. This hypothesis was confirmed by surface photovoltage spectroscopy, piezoelectric current response, and electrochemical analysis. Consequently, the ZnSnO3/Bi4Ti3O12 composite exhibited significantly improved piezocatalytic performance in RhB degradation, achieving a degradation efficiency of 80 % within 90 min under ultrasonic vibration. The degradation rate of the optimal sample was 8.2 times that of Bi4Ti3O12 and 6.3 times that of ZnSnO3. Additionally, experiments to detect reactive species were conducted to elucidate the mechanism behind the piezocatalytic RhB degradation. Holes and hydroxyl radicals were the main reactive species. This study may offer new insights into the design of efficient piezocatalytic materials.

New spacious SrWO4/PEDOT-PPy nanohybrids and their electrochemical and photocatalytic activities

A novel SrWO4-poly(3,4-ethylene dioxythiophene) (PEDOT)-polypyrrole (PPy) nanocomposite was synthesized via chemically oxidative polymerization and considered by using numerous method of the techniques. The resulting SrWO4/PEDOT-PPy nanocomposite demonstrated remarkable electrochemical sensing capabilities for sulfadiazine (SFA). As a modified glassy carbon electrode (SrWO4/PEDOT-PPy/GCE) revealed for superior catalytic activity in the electrochemical oxidation of sulfadiazine, enabling sensitive detection with quantification and detection limits of 1.0936 × 10-9 M µA-1 and 2.2104 × 10-9 M µA-1, respectively. This technique effectively determined SFA content in real samples. Additionally, SrWO4/PEDOT-PPy demonstrated extraordinary photocatalytic ability, achieving a Methylene Blue (MB) degradation rate of up to 99.1% under halogen light irradiation within 80 min. Hybrid photocatalyst has exhibited to strong reusability and photocatalytic stability under frequent light exposure. A contrivance for the photocatalytic deprivation of MB by SrWO4/PEDOT-PPy is proposed. These results underscore the crucial role of SrWO4/PEDOT-PPy in practical environmental remediation analysis. The fluorescence investigations have betrothed to terephthalic acid radical formations of SrWO4/PEDOT-PPy hybrids, which were modulated by different approaches, and its mainly driven for higher illumination aptitudes. Meanwhile, this was more supporting for physio-chemical properties of the phenomenon, at this consequential with significantly well improved to the photocatalytic performances. Because of this, SrWO4/PEDOT-PPy hybrid materials were comprehended to deliver excellent kinetics, and better recyclable activities.

Enhancement of the photocatalytic activity of rGO/NiO/Ag nanocomposite for degradation of methylene blue dye

The current study focuses on boosting the photocatalytic ability of reduced graphene oxide (rGO) by decorating the rGO nano-sheets with nickel oxide (NiOx) and silver (Ag) nanomaterials. The developed ternary nanomaterials were investigated using FTIR, XRD, FESEM, TEM, Raman, and UV-vis to evaluate the photo-degradation process. The rGO/NiOx/Ag ternary system showed promising photocatalytic dye degradation under simulated sunlight irradiance. The addition of NiOx and Ag nanomaterials widened the catalytic activity spectrum from the visible region to the UV-region. Besides, these materials hindered the electron-hole recombination, boosting the catalytic activity. The reusability results also clearly showed that the synthesized ternary nanomaterials have good reproducibility and stability for photocatalytic degradation of industrial wastewater.

Comprehensive review of micro/nanostructured ZnSnO3: characteristics, synthesis, and diverse applications

Generally, zinc stannate (ZnSnO3) is a fascinating ternary oxide compound, which has attracted significant attention in the field of materials science due to its unique properties such high sensitivity, large specific area, non-toxic nature, and good compatibility. Furthermore, in terms of both its structure and properties, it is the most appealing category of nanoparticles. The chemical stability of ZnSnO3 under normal conditions contributes to its applicability in various fields. To date, its potential as a luminescent and photovoltaic material and application in supercapacitors, batteries, solar cells, biosensors, gas sensors, and catalysts have been extensively studied. Additionally, the efficient energy storage capacity of ZnSnO3 makes it a promising candidate for the development of energy storage systems. This review focuses on the notable progress in the structural features of ZnSnO3 nanocomposites, including the synthetic processes employed for the fabrication of various ZnSnO3 nanocomposites, their intrinsic characteristics, and their present-day uses. Specifically, we highlight the recent progress in ZnSnO3-based nanomaterials, composites, and doped materials for their utilization in Li-ion batteries, photocatalysis, gas sensors, and energy storage and conversion devices. The further exploration and understanding of the properties of ZnSnO3 will undoubtedly lead to its broader implementation and contribute to the advancement of next-generation materials and devices.

Novel Bi2WO6/ZnSnO3 heterojunction for the ultrasonic-vibration-driven piezocatalytic degradation of RhB

This study designed and prepared a new piezoelectric catalytic nanomaterial, Bi₂WO₆/ZnSnO₃, and applied it in piezocatalytic water purification. Results indicated that the composite had superior piezocatalytic efficiency and stability in rhodamine B (RhB) degradation under ultrasonic vibration. The Bi₂WO₆/ZnSnO₃ sample with 10% Bi₂WO₆ had the optimum activity with a degradation rate of 2.15 h^-1, which was 7.4 and 11.3 times that of ZnSnO₃ and Bi₂WO₆, respectively. Various characterizations were conducted to study the morphology, structure, and piezoelectric properties of the Bi₂WO₆/ZnSnO₃ composites and reveal the reasons for their improved piezocatalytic performance. Results showed that ZnSnO₃ cubes were dispersed throughout the surface of Bi₂WO₆ nanosheets, which enhanced the specific surface area and facilitated the piezocatalytic reaction. Additionally, type-II heterojunction structures formed at the contact interface of Bi₂WO₆ and ZnSnO₃, driving the migration of piezoelectric-induced electrons and holes. Accordingly, the separation efficiency of charge carriers improved, and the piezoelectric catalytic activity was significantly enhanced. This study may provide a potential composite catalyst and a promising idea for the design of highly efficient piezoelectric catalyst.

New development and photocatalytic performance and antimicrobial activity of α-NH4(VO2)(HPO4) nanosheets

α-NH₄(VO₂)(HPO₄) nanosheets were developed by hydrothermal method. Furthermore, it's determined by the several analyses like XRD, Raman, FESEM, TEM, UV-Visible spectroscopy, TGA and DRS UV-Visible spectroscopy studies. The orthorhombic crystalline phase of α-NH₄(VO₂)(HPO₄) nanosheets were recognized by XRD analysis. The α-NH₄(VO₂)(HPO₄) nanosheets functional groups identification was investigated by Raman spectroscopy. Thermal gravimetric analysis of α-NH₄(VO₂)(HPO₄) nanosheets were identified and its attain for three decomposition stages. The nanosheets of the α-NH₄(VO₂)(HPO₄) was clearly evaluated by FESEM and TEM measurements. α-NH₄(VO₂)(HPO₄) nanomaterial band gap energy was determined by DRS UV Visible spectroscopy analysis and the calculated bandgap energy is 1.83 eV. Hence, it was more convenient way for the dye degradation applications. These α-NH₄(VO₂)(HPO₄) nanosheets was will be tested in the photocatalytic and antimicrobial applications. In this case, antimicrobial study was not encouraged in the catalyst. Consequently, this material has more encouraging for electrostatic interaction with enhanced for the applications.

Ultrasound-Assisted Hydrothermal Synthesis of SrSnO3/g-C3N4 Heterojunction with Enhanced Photocatalytic Performance for Ciprofloxacin under Visible Light

In this work, an SrSnO3/g-C3N4 heterojunction with different dosage of SrSnO3 was fabricated by an ultrasound-assisted hydrothermal approach and characterized by X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), X-ray photoelectron spectroscopy (XPS), scanning electron microscopy (SEM), transmission electron microscopy (TEM), UV-visible diffuse reflectance spectra (UV-Vis DRS), and photoluminescence spectroscopy (PL). Ciprofloxacin was adopted to assess the degradation performance, and the sample combined with 40% SrSnO3 eliminated 93% of ciprofloxacin (20 mg/L) within 3 h under visible light, which is 6.6 and 1.7 times greater than for SrSnO3 and g-C3N4, respectively. Furthermore, 85% CIP was extinguished after five cycles of a photocatalytic process. Ultimately, a possible photocatalytic mechanism was dissected.

Recent Advances on Properties and Utility of Nanomaterials Generated from Industrial and Biological Activities

Today is the era of nanoscience and nanotechnology, which find applications in the field of medicine, electronics, and environmental remediation. Even though nanotechnology is in its emerging phase, it continues to provide solutions to numerous challenges. Nanotechnology and nanoparticles are found to be very effective because of their unique chemical and physical properties and high surface area, but their high cost is one of the major hurdles to its wider application. So, the synthesis of nanomaterials, especially 2D nanomaterials from industrial, agricultural, and other biological activities, could provide a cost-effective technique. The nanomaterials synthesized from such waste not only minimize pollution, but also provide an eco-friendly approach towards the utilization of the waste. In the present review work, emphasis has been given to the types of nanomaterials, different methods for the synthesis of 2D nanomaterials from the waste generated from industries, agriculture, and their application in electronics, medicine, and catalysis.

Fabrication of different SnO2 nanorods for enhanced photocatalytic degradation and antibacterial activity

The acid-mediated (oxalic acid [OXA], cinnamic acid [CA], and itaconic acid [IA]) SnO₂ nanorods were synthesized by the hydrothermal method. The synthesized SnO₂ nanorods, in turn, were analyzed with various physico-chemical techniques such as the X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FT-IR), scanning electron microscope (SEM), and Raman spectroscopy. Furthermore, the photocatalytic activity of the different SnO₂ nanorods was investigated with the malachite green (MG) dye under visible light illumination. The OXA-SnO₂ nanorods displayed an excellent degradation performance with observed value at 91% and it was compared to CA and IA-SnO₂ nanomaterials. This tetragonal phase was identified and confirmed by XRD studies. In this regards, obtained band gap energy is low then optimally performed to the photocatalytic evolution. The OXA-SnO₂ materials were tested for antibacterial and antifungal studies; this was as shown in good biological activities with admire to the different bacterial strains. The Candida albicans (antifungal) and Enterococcus faecalis (Gram-positive) bacteria were not affected in the microbial studies.

The fate of oxygen on graphene-catalyst in the photocatalytic water splitting reaction

This paper reveals the transformation of oxygen on graphene in the water splitting process and for the first time, points out a step by step dehydrogenation process with the intermediates OH–C and O–C, and finally CO2.