Solar-driven electrolysis coupled with valuable chemical synthesis

The energy transition requires the development of clean energy alternatives and more sustainable methods for chemical production. For instance, alternative reactions to replace conventional hydrogenation processes, which typically require high temperatures and pressures, are needed. Solar-driven (photo)electrolysis can convert chemicals into value-added products without the need for energy-intensive processes such as heating. In this Review, we outline valuable electrochemical synthetic approaches that are driven by sunlight (either directly or indirectly) and include alternative reactions that replace O2 evolution, hydrogenate feedstocks using water as the proton source or integrate downstream utilization of H2 in the same device. We categorize feedstocks and products into four quadrants based on their market price and demand. Comparative techno-economic assessments suggest that centralized single-product facilities are more suitable for chemicals from the second quadrant (low market price and high demand), whereas chemicals in the fourth quadrant (high market price and low market demand) are best suited for decentralized facilities that generate multiple products. For future practical solar electrolysis, oxidation and reduction reactions should be chosen based on their economic value and feasibility. © 2025, Springer Nature Limited.