Recent advances in photocatalytic hydrogen evolution and oxidation performance of Ta₂O₅ based materials: A comprehensive review

Tantalum pentoxide (Ta₂O₅) has recently attracted significant attention as a promising photocatalyst for environmental remediation and solar-driven hydrogen production due to its strong oxidation capability, high chemical stability, and favorable electronic band structure. Although numerous studies have explored various synthesis methods for Ta₂O₅-based materials, the existing literature predominantly emphasizes fabrication techniques while providing comparatively limited insight into the actual photocatalytic performance of these systems. In contrast, this review focuses on the outcomes rather than the synthesis approaches, presenting a comprehensive evaluation of the oxidation efficiencies, hydrogen production capacities, and operational stability of Ta₂O₅-based photocatalysts. Attention is given to the key parameters influencing photocatalytic performance, including catalyst composition, dopant types, nanostructure morphology, light source characteristics, pH conditions, and reaction time. Through comparative analysis of reported studies, the review highlights how structural modifications such as doping, defect engineering, nano structuring, and heterojunction formation significantly improve light absorption, charge carrier separation, and catalytic activity. The results demonstrate that modified Ta₂O₅ systems can achieve degradation efficiencies exceeding 90% for various organic pollutants and improved hydrogen evolution performance under optimized conditions. Furthermore, stability and recyclability analyses confirm the durability of Ta₂O₅ photocatalysts in repeated operation cycles. This review provides a performance-oriented perspective on Ta₂O₅ photocatalysis and offers insights into future strategies for developing efficient photocatalysts for sustainable wastewater treatment and solar-to-hydrogen energy conversion.