In today’s energy transition contest, where reducing carbon emissions is crucial, green hydrogen offers a promising means to store and valorize solar energy. Photoelectrocatalysis (PEC) and photocatalysis (PC) technologies enable the direct conversion of photons into hydrogen via semiconductors, bypassing the intermediate electricity generation step and paving the way for modular, stand-alone systems ideally suited to remote sites or integration with small-scale photovoltaic plants. Despite their potential, these approaches can be significant improved. First, efficiency remains low: many semiconductors fail to harvest the full solar spectrum and suffer losses from rapid electron–hole recombination, penalizing solar-to-hydrogen yields. At the same time, material stability is challenged by photochemical corrosion and surface passivation, which quickly degrade performance in the absence of suitable protective coatings. Finally, industrial-scale synthesis is often costly and complex, as many advanced materials require elaborate fabrication processes. To address these critical issues, the session will focused into several emerging research. One particularly promising frontier is hybrid metal-organic perovskites, which combine exceptional charge mobility with tunable band gaps and energetic alignments with catalytic materials; to fully harness their potential, however, robust encapsulation and interface-engineering strategies are essential to ensure operational stability and durability. A second focus will be on charge-transport materials—crucial for rapid carrier extraction and recombination suppression.
Finally, advanced catalysts designed to enhance reaction kinetics will be explored. Throughout the session, these challenges will be critically assessed and potential solutions discussed, with the aim of defining shared guidelines to make PEC and PC competitive technologies for solar-driven hydrogen production.