Bifunctional Co3O4/g-C3N4 Hetrostructures for Photoelectrochemical Water Splitting.

This study explored the synergistic potential of photoelectrochemical water splitting through bifunctional Co3O4/g-C3N4 heterostructures. This novel approach merged solar panel technology with electrochemical cell technology, obviating the need for external voltage from batteries. Scanning electron microscopy and X-ray diffraction were utilized to confirm the surface morphology and crystal structure of fabricated nanocomposites; Co3O4, Co3O4/g-C3N4, and Co3O4/Cg-C3N4. The incorporation of carbon into g-C3N4 resulted in improved catalytic activity and charge transport properties during the visible light-driven hydrogen evolution reaction and oxygen evolution reaction. Optical properties were examined using UV-visible spectroscopy, revealing a maximum absorption edge at 650 nm corresponding to a band gap of 1.31 eV for Co3O4/Cg-C3N4 resulting in enhanced light absorption. Among the three fabricated electrodes, Co3O4/Cg-C3N4 exhibited a significantly lower overpotential of 30 mV and a minimum Tafel slope of 112 mV/dec This enhanced photoelectrochemical efficiency was found due to the established Z scheme heterojunction between Co3O4 and gC3N4. This heterojunction reduced the recombination of photogenerated electron-hole pairs and thus promoted charge separation by extending visible light absorption range chronoamperometric measurements confirmed the steady current flow over time under constant potential from the solar cell, and thus it provided the effective utilization of bifunctional Co3O4/g-C3N4 heterostructures for efficient solar-driven water splitting.

Non-enzymatic glucose sensor with electrodeposited silver/carbon nanotubes composite electrode.

Diabetes mellitus is a debilitating disease that affects each and every organ of human body. Hence it is important to continuously monitor the glucose level throughout the day and night. Glucose sensors are in great demand due to a rapid increase in diabetic community. A strategy has been implemented here to fabricate silver nanoparticles (AgNPs) with the support of functionalized carbon nanotubes (f-CNTs). Silver/carbon nanotubes (Ag/CNTs) nanocomposite electrode have been prepared by electrochemical process on Fluorine doped tin oxide (FTO) glass, by varying silver (Ag) concentrations for non-enzymatic glucose sensor. The variable Ag concentration in the morphology of Ag/CNTs nanocomposite has influenced the electrical conductivity, oxidation and reduction potential and electrochemical activity of glucose. Highest current density and good electrocatalytic activity for electrodes are obtained at 70 mM concentration of silver in Ag/CNTs composite. The present study indicates that the Ag/CNTs electrode is a possible substitute of the expensive glassy carbon electrode for enzyme-free glucose sensors.

Facile Microemulsion Synthesis of Vanadium-Doped ZnO Nanoparticles to Analyze the Compositional, Optical, and Electronic Properties.

In this work, microemulsion method has been followed to synthesize vanadium-doped Zn1-xVxO (with x = 0.0, 0.02, 0.04, 0.06, 0.08, and 0.10) nanoparticles. The prepared samples are characterized by several techniques to investigate the structural, morphology, electronic, functional bonding, and optical properties. X-ray diffractometer (XRD) analysis confirms the wurtzite phase of the undoped and V-doped ZnO nanoparticles. Variation in the lattice parameters ensures the incorporation of vanadium in the lattice of ZnO. Scanning electron microscopy (SEM) shows that by increasing contents of V ions, the average particle size increases gradually. X-ray Absorption Near Edge Spectroscopy (XANES) at the V L3,2 edge, oxygen K-edge, and Zn L3,2 edge reveals the presence and effect of vanadium contents in the Zn host lattice. Furthermore, the existence of chemical bonding and functional groups are also asserted by attenuated total reflection Fourier transform infrared spectroscopy (ATR-FTIR). UV⁻Visible analysis shows that by increasing V⁺ contents, a reduction up to 2.92 eV in the energy band gap is observed, which is probably due to an increase in the free electron concentration and change in the lattice parameters.