Photocatalytic Hydrolysis of Silicon Hydrides for On-Demand Green Hydrogen Production under Natural Sunlight

Developing an innovative strategy for efficient, on-demand, and on-site production of green hydrogen from waste and renewable resources could offset the cost of the transport and storage of hydrogen. Here, we establish nanoparticle-assisted photocatalytic silicon hydride (silane) hydrolysis as an effective strategy for the on-demand production of green hydrogen from sunlight without electricity. Furthermore, this process produces silanol and siloxanes as value-added side products with extensive industrial applications. We demonstrated that this process works with all visible and NIR wavelengths with a maximum absolute photon-to-hydrogen conversion efficiency (IPHCE), reaching 0.66% at 808 nm. It also has a broad substrate scope and works with primary to tertiary silanes. Besides green hydrogen production, we also report a photocatalytic pathway for synthesizing polysiloxanes from the hydrolysis of primary and secondary hydrosilanes. Finally, we demonstrated on-demand hydrogen production from methyl phenyl silane under natural sunlight with an appreciable hydrogen production rate of approximately 19.6 L m^-2 h^-1. These results demonstrate the suitability of photocatalytic silicon hydride hydrolysis as a highly potent strategy for setting up domestic-scale, on-demand hydrogen production units at remote locations.