Recent progress on visible active nanostructured energy materials for water split generated hydrogen

Solar-driven water splitting is one amongst the fastest growing areas of research for hydrogen evolution. The technology employs application of nanostructured energy materials with featured charge-separation and light absorption characteristics. The high charge-carrier recombination and wide band-gap of energy materials are major material-related bottlenecks that restricted the large-scale implementation. Besides it, the co-catalyst, electron mediator and sacrificial electron donor (SED) were the other major components for further improving the H-2 yield. A water splitting reactor with well-optimized photon and mass transfer properties is mandatory for studying hydrogen evolution at large scale. The present review compiles various strategies that were presented for reducing charge-carrier recombination and extending visible light absorption of materials, insights for loading earth-abundant co-catalysts on photocatalyst surface, recently developed reversible redox and non-noble metal-based solid-state electron mediators and advantage of applying organic contaminant and biomass-derived waste as SEDs. The discussions on several engineered reactor designs for the photocatalytic water splitting technology were also presented. A cost-effective way of designing a photocatalytic water splitting system with functionalized nanostructured energy materials, the earth-abundant co-catalysts, organic waste-based electron donors and efficient electron mediators for achieving improved hydrogen evolution rate is comprehensively discussed. [GRAPHICS] .

Automated summary

Solar-driven water splitting technology is rapidly growing in the field of hydrogen evolution research, utilizing nanostructured energy materials with specific characteristics. Current research focuses on addressing issues such as charge-carrier recombination and limited light absorption range of materials, with the use of co-catalysts and sacrificial electron donors to enhance H-2 yield. Strategies include developing earth-abundant co-catalysts and non-noble metal-based electron mediators for improving hydrogen evolution rate.