Recent Developments of Scalable Photocatalytic Reactors for Green Hydrogen Production

Water splitting for hydrogen generation under exposure to sunlight is an excellent technique for generating sustainable power and mitigating the consequences of climate change. Numerous attempts have been made to synthesize superior nano-composite elements. Several constraints still prevail at every stage of the development of a photoreactor system, from the scalable production of the photocatalyst (PC) material to the fabrication of an ideal photocatalyst structure having a high transfer of mass, effective charge carrier separation, high charge carrier mobility, required bandgap and band edge positions, effective photon absorption, and stability. In this chapter, recent developments in photocatalysts, including metal doping, surface photosensitization, defect engineering, copolymerization, and novel architectures, are discussed. The design of the photoreactor system is also a major concern, as it plays a significant role in achieving the desired output. This chapter aims to give a thorough explanation of the main obstacles encountered while scaling up PC devices and also to suggest some possible remedies for its use in commercially viable generation of solar hydrogen. In conclusion, the important aspects influencing performance have been highlighted, and recommendations for future research based on an assessment of the most recent experimental developments have been proposed.