Advances and challenges in photocatalytic water splitting: recent developments and trends

Abstract

Photocatalytic hydrogen generation using sunlight is an innovative approach to address the pressing issues of energy scarcity aligning with Sustainable Development Goals (SDGs) such as affordable and clean energy (SDG 7) and climate action (SDG 13). This review explores recent advancements in photocatalytic materials designed to efficiently convert solar energy into hydrogen, focusing on the development of robust photocatalysts that operate under visible to near infrared light. Key technical strategies include optimization through doping, heterojunction construction, morphological tuning, and crystallinity enhancement, which collectively improve the photocatalyst's ability to absorb and utilize solar energy. Furthermore, the integration of photosensitizers, co-catalysts, and plasmonic materials has significantly enhanced the efficiency of the hydrogen evolution reaction (HER). Despite these advancements, challenges such as the reverse reaction kinetics of water splitting, light intensity dependence, sacrificial reagent optimization, and reaction temperature control remain. This review provides a comprehensive summary on these critical parameters and their impact on solar-to-hydrogen conversion efficiency. It also highlights current advancements in manufacturing techniques and identifies key research gaps. This review concludes a discussion on overcoming existing challenges and suggests pathways for future research to advance the development of highly efficient semiconducting photocatalysts for large-scale hydrogen production, contributing to global sustainability efforts.