Bi2S3 nanoparticles by facile chemical synthesis: Role of pH on growth and physical properties

Nature-Inspired Vertically Oriented 1D Bi2S3 Surface Nanorods for Ultra-Selective Electrochemical Sensing of Mancozeb

The issue of environmental contamination is becoming increasingly critical as industrial and agricultural activities continue to grow. As a result, there is a growing need for fast and accurate methods to detect and determine pesticide residues in environmental samples. This study highlights the development of nature-inspired 1D Bi2S3 vertically oriented nanorods on fluorine-doped tin oxide glass (Bi2S3-VONs(nat)/FTO) using the vegetal extract of Sechium edule (S. edule) for electrochemical detection of mancozeb (MCZ) in environmental matrices. The phytochemicals in the S. edule extract were utilized to promote the growth and stabilization of Bi2S3 VONs. The Bi2S3 nanorods synthesized at 2.3 g of Bi(NO3)3·5H2O and pH 3 (2.3Bi2S3-VONs(nat)/FTO@pH3) exhibit ∼1.74 ± 0.09 μm vertical length with a high surface roughness (67.5% higher than FTO(bare)). The 2.3Bi2S3-VONs(nat)/FTO@pH3 electrode exhibited an 89.2% reduction in charge transfer resistance (Rp), a 64.4% increase in the effective surface area (Ae), and a 68.7% enhancement in the anodic peak current of MCZ compared to the FTO(bare). The detection of MCZ at 2.3Bi2S3-VONs(nat)/FTO@pH3 involved a reversible four-electron diffusion-controlled event with a formal potential (E0) of 0.655 V vs Ag/AgCl, a rate constant (k0) of 0.011 s-1, and a surface coverage of MCZ ions (Γ*) of 1.126 × 10-11 mol cm-2. 2.3Bi2S3-VONs(nat)/FTO@pH3 demonstrated a detection limit of 0.0085 μM, a quantification limit of 0.0284 μM, and a sensitivity of 0.1578 μA·μM-1·cm-2 within a working range of 0-200 μM. Commonly used pesticides, such as chlorpyrifos, carbendazim, malathion, thiram, ziram, and profenofos, could not interfere with MCZ detection. Only a 16.4% reduction in the peak current was observed up to the 30th run when the same sensing platform was reused. 2.3Bi2S3-VONs(nat)/FTO@pH3 could effectively detect MCZ spiked in the environmental matrices, which are comparable to liquid chromatography, with a maximum deviation of 4.1, 4.9, 7.1, and 9.7% recorded for tap water, river water, agricultural runoff, and wastewater, respectively.

Lab-on-a chip electrochemical sensing platform for simultaneous, ultra-sensitive and on-spot detection of 4-aminosalicylic acid and 5-aminosalicylic acid based on synergistic potential of chitosan functionalized MWCNTs supported on Ni doped Bi2S3

Mesalamine or 5-aminosalicylic acid (5-ASA) and its isomer 4-aminosalicylic acid (4-ASA), well known key therapeutic agents used to treat inflammatory bowel diseases (IBDs) can pose toxicity risks upon unregulated consumption. However, their simultaneous real-time detection from physiological fluids like urine remains unexplored. This study presents an innovative electrochemical sensing platform using modified screen-printed electrodes capable of simultaneous detection of both the drugs by harnessing the synergistic potential of a novel nanocomposite comprising chitosan functionalized multi-walled carbon nanotubes and nickel doped bismuth sulphide. Comprehensive optical and microstructural characterization validate the modified sensor platform's morphological characteristics. The sensor was evaluated using CV and DPV, exhibiting notably low detection limits which is of the value 39.559 μM for 5-ASA and 85.21 μM for 4-ASA. Sensitivity was found to be 0.174 μA μM-1cm-2 for the linear dynamic range (LDR) of 50 μM-5750 μM for 5-ASA and 0.139 μA μM-1cm-2 for the linear dynamic range (LDR) of 100 μM-2200 μM for 4-ASA. Moreover, the adaptability of the sensor for integration into hand-held point-of-care devices for practical application has been demonstrated in this paper. Experimental validation using real urine samples underscores the sensor's impressive recovery rate of 98-99.6 % for 5-ASA and 95.12-99.24 % for 4-ASA and its capability of detecting target drugs even when present with typical urinary constituents as interferences. The real-world applicability of this sensing platform is further emphasized by conducting experiments on miniaturized hand-held device thus making it a promising tool for on-the-spot detection, offering substantial potential for future integration into point-of-care diagnostic devices to monitor patients requiring precise medical monitoring. Our approach offers unprecedented real-time identification capabilities of 4-ASA and 5-ASA which has not been explored before.

Solution-synthesized nanostructured materials with high thermoelectric performance

Facing the growing scarcity of traditional fossil fuels and the inefficiency of energy utilization, thermoelectric materials have garnered increasing attention due to their ability to convert between electrical and thermal energy. However, the strong coupling between thermoelectric parameters presents a significant challenge for simultaneously reducing thermal conductivity and maintaining electrical performance in bulk materials. The solution-based synthesis of nanostructured materials offers a promising approach for the decoupling regulation of electronic and phonon transport properties by regulating grain size and morphology, second phases, and surface ligands. The strategies for optimizing thermoelectric performance outlined above are founded upon several pivotal elements: the enhancement of grain boundary effects, precise regulation of grain stacking, utilization of heterogeneous interface effects, and generation of metastable phases and novel structural configurations facilitated by ligand management approaches. We have also comprehensively addressed the challenges associated with solution-based synthesis, particularly material oxidation and grain coarsening, along with their corresponding mitigation strategies. In addition, machine learning can effectively accelerate solution synthesis and the exploration of composite materials. This review summarizes and generalizes the research related to these strategies, providing recommendations for future research directions based on observed trends.

Ultrasonic treatment-assisted reductive deposition of Cu and Pd nanoparticles on ultrathin 2D Bi2S3 nanosheets for selective electrochemical reduction of CO2 into C2 compounds

In this work, we have ultrasonically deposited Cu and Pd nanoparticles on Bi2S3 nanoparticles, prepared using an ultrasonication assisted hydrothermal method. We implemented intense ultrasonic waves bearing frequency of 20 kHz and power of 750 W at the acoustic wavelength of 100 mm to reduce Cu and Pd nanoparticles on the Bi2S3 surface. The XRD confirmed the formation of highly crystalline Bi2S3 nanoparticles with a pure orthorhombic phase and the deposition of copper (Cuo) and palladium (Pdo) nanoparticles was indicated by the strengthening and broadening of the peaks. XPS also confirmed the formation of Cuo and Pdo nanoparticles on Bi2S3. The Transmission Electron Microscopy (TEM) also exhibited the deposition of Cu and Pd nanoparticles on the Bi2S3 nanosheets which was further confirmed using high resolution TEM analysis. The electrochemical CO2 reduction by Cu-Pd/Bi2S3 electrocatalyst using Cu foam as the conducting support led to the formation of acetaldehyde and ethylene as the major products. The rate of formation of ethylene was found to be 488.5 μ mol g-1h-1 at an applied potential of -0.6 V (vs. RHE), with the best Faradaic efficiency of 57.09 % at -0.4 V (vs. RHE). Among the liquid phase products, acetaldehyde was the major product showing the maximum Faradaic efficiency of 6.473 % at -0.2 V (vs. RHE), with a total formation rate of 64.27 μ mol g-1h-1. The results revealed that the Cu-Pd/Bi2S3 electrocatalyst was more selective to C2 products while the pure Bi2S3 nanoparticles majorly produced C1 compounds.

The versatile biomedical applications of bismuth-based nanoparticles and composites: therapeutic, diagnostic, biosensing, and regenerative properties

Studies of nanosized forms of bismuth (Bi)-containing materials have recently expanded from optical, chemical, electronic, and engineering fields towards biomedicine, as a result of their safety, cost-effective fabrication processes, large surface area, high stability, and high versatility in terms of shape, size, and porosity. Bi, as a nontoxic and inexpensive diamagnetic heavy metal, has been used for the fabrication of various nanoparticles (NPs) with unique structural, physicochemical, and compositional features to combine various properties, such as a favourably high X-ray attenuation coefficient and near-infrared (NIR) absorbance, excellent light-to-heat conversion efficiency, and a long circulation half-life. These features have rendered bismuth-containing nanoparticles (BiNPs) with desirable performance for combined cancer therapy, photothermal and radiation therapy (RT), multimodal imaging, theranostics, drug delivery, biosensing, and tissue engineering. Bismuth oxyhalides (BiO_x, where X is Cl, Br or I) and bismuth chalcogenides, including bismuth oxide, bismuth sulfide, bismuth selenide, and bismuth telluride, have been heavily investigated for therapeutic purposes. The pharmacokinetics of these BiNPs can be easily improved via the facile modification of their surfaces with biocompatible polymers and proteins, resulting in enhanced colloidal stability, extended blood circulation, and reduced toxicity. Desirable antibacterial effects, bone regeneration potential, and tumor growth suppression under NIR laser radiation are the main biomedical research areas involving BiNPs that have opened up a new paradigm for their future clinical translation. This review emphasizes the synthesis and state-of-the-art progress related to the biomedical applications of BiNPs with different structures, sizes, and compositions. Furthermore, a comprehensive discussion focusing on challenges and future opportunities is presented.