Photoelectrochemical Gas-Electrolyte-Solid Phase Boundary for Hydrogen Production From Water Vapor.

Hydrogen production from humidity in the ambient air reduces the maintenance costs for sustainable solar-driven water splitting. We report a gas-diffusion porous photoelectrode consisting of tungsten trioxide (WO) nanoparticles coated with a proton-conducting polymer electrolyte thin film for visible-light-driven photoelectrochemical water vapor splitting. The gas-electrolyte-solid triple phase boundary enhanced not only the incident photon-to-current conversion efficiency (IPCE) of the WO photoanode but also the Faraday efficiency (FE) of oxygen evolution in the gas-phase water oxidation process.

Solid Polymer Electrolyte-Coated Macroporous Titania Nanotube Photoelectrode for Gas-Phase Water Splitting.

Photoelectrochemical (PEC) water vapor splitting by using n-type semiconductor electrodes with a proton exchange membrane (PEM) enabled pure hydrogen production from humidity in ambient air. We proved a design concept that the gas-electrolyte-semiconductor triple-phase boundary on a nanostructured photoanode is important for the photoinduced gas-phase reaction. A surface coating of solid-polymer electrolyte on a macroporous titania-nanotube array (TNTA) electrode markedly enhanced the incident photon-to-current conversion efficiency (IPCE) at the gas-solid interface.