Exploring strategies for enhancing photocatalytic activity of SmVO4-based heterojunctions formation for water purification

Background

Semiconductor-based heterojunctions in the realm of photocatalysis has attracted significant consideration among scientific community as a promising strategy to advance environmentally resilient development for long-term generational benefit. This approach has been acknowledged as an effective solution to ameliorate the ongoing environmental crisis. Samarium vanadate (SmVO₄), a fascinating rare earth metal orthovanadate, has been the focal point in the solar-driven applications due to optimal band positions and a narrow band gap, thereby broadening the absorption capacity within the visible light region. It also acts as a highly effective photocatalyst for many reactions, such as the dehydrogenation of alkanes, olefins, etc.

Methods

To address the broad spectrum of photocatalytic application demands, the bare photocatalyst is ineffective owing to its limitations, such as high recombination rate, agglomeration, low surface area, etc. Therefore, various strategies were explored and implemented by the researchers to mitigate the above-mentioned shortcomings and to improve the overall photocatalytic performance. To fill this gap, the review systematically elucidates the crystallographic, electronic and optical properties, followed by synthesis methods. Thereafter, modification strategy i.e., heterojunction formation via integrating bare SmVO₄ with other semiconductors such as metal oxide, metal-free, metal halide, metal organic frameworks, insulating material and more was analysed.

Significant findings

This approach increases the surface area, chemical stability, facilitates the charge-segregation capability, offers more active sites and exhibits high quantum efficiency. The various photocatalytic applications, including antibiotic, dye, and heavy metal degradation via SmVO₄-based heterojunctions were examined, aligning with the United Nations Sustainable Development Goals-6 i.e., clean water and sanitation. Finally, the article concluded with key issues and future directions related to SmVO₄-based heterojunctions for sustainable living.