Light-driven simultaneous water purification and green energy production by photocatalytic fuel cell: A comprehensive review on current status, challenges, and perspectives

Solar energy is a crucial source that sustains all life and activities on Earth. Photocatalysis based on solar energy is an exciting technology with great potential for solving complex problems, including environmental pollution, energy crisis, and global warming. Over the past few decades, significant efforts have been made in developing photocatalytic techniques. One particularly promising area is the use of photocatalytic fuel cells (PFCs) for light-driven wastewater remediation and energy generation, which has gained considerable attention due to its ability to simultaneously remove organic pollutants and generate electricity/hydrogen using sunlight alone. In this review, we comprehensively assess recent progress in the development of photoanode/photocathode materials, cathode materials, system configurations, and radical reaction processes. We also summarize five key strategies to improve system dynamics and charge transfer properties. By highlighting the significance of designing and implementing PFCs as alternatives to traditional technologies, we provide insights into future research directions necessary for the advancement of highly efficient PFCs. Furthermore, we extensively discuss the challenges, perspectives, and future studies for various PFC or hybrid systems, and also the cost analysis of PFC based wasterwater treatment technique. Addressing challenges related to catalyst design, charge carrier dynamics, mass transport, system integration, and scalability, along with exploring environmental applications, advanced characterization techniques, combining with machine learning, system optimization, and control, will pave the way for the successful implementation and widespread adoption of PFCs.