OXYGEN EVOLUTION REACTION BY USING PHOTOANODIC TA3N5 FOR WATER SPLITTING PROCESS BY DIFFERENT SURFACE MODIFICATION: A REVIEW

Abstract

Fossil energy is a widely used energy source these days, but because of the fossil usage; many complications also arise. In response, a global shift toward sustainable and renewable energy sources has amplified interest in photoelectrochemical (PEC) water splitting as a viable route for clean hydrogen production. Water splitting, which involves the decomposition of water into hydrogen and oxygen, depends critically on the development of efficient and stable semiconductor photoanodes. For this reason, many semiconductors are used; but titanium nitride (Ta₃N₅) semiconductor has great importance because of the low-over potential, better band structure, lesser charge transfer resistance (Rct), decreased solution resistance (Rs), maximum current density and abundance. However, the practical application of Ta₃N₅ is limited by poor charge mobility, surface instability, and rapid electron-hole recombination. To overcome these limitations, significant research has been carried out to prepare the nanocomposites of Ta₃N₅ such as nanofibers, nanofilms, micro sheets, dum bell-like nanostructures, and nanoflowers. These varied morphologies not only enhance visible-light harvesting and charge separation but also lower overpotential and suppress recombination losses, thus improving the overall efficiency of PEC water splitting. Furthermore, a variety of synthetic methodologies including hydrothermal, sol-gel, electrospinning, electrochemical, precipitation, and chemical reduction techniques helped in achieving uniform doping, nanoscale control, and enhanced structural stability. In conclusion, Ta₃N₅ is of significant interest in semiconductor research for water splitting applications. However, future research must focus on improving long-term operational stability, enhancing charge transport across interfaces, and integrating Ta₃N₅ into tandem PEC cells or hybrid solar fuel systems.