Optical and electrochemical effects of H2 and O2 bubbles at upward-facing Si photoelectrodes

摘要: The effects of the size, contact-angle, and coverage gas bubbles on solar fuels devices were characterized at cm-scale, upward-facing planar microwire-array Si photoelectrodes in stagnant electrolytes. Experimental measurements supported by ray-tracing simulations surface attached bubble films. A dilute, redox-active tracer allowed for quantification mass-transport during photoanodic O2(g) evolution photoanodes 1.0 M KOH(aq.). Measurements p-Si photocathodes 0.50 H2SO4(aq.) nucleation rate contact angle H2(g) to be evaluated systems having various free energies. Under simulated illumination, rapid departure small produced stable photocurrents oxygen-evolving yielded increased velocities relative a electrolyte, indicating that can provide net benefit photoelectrochemical performance an photoanode devices.