Fig. 2: Photocathodes evaluated in a two-electrode configuration.

a The initial 10 h of the chronoamperometry (CA) stability test of the photocathode at −2.3 V vs. IrOx under AM 1.5 G one-sun illumination in 0.5 M H2SO4 with 0.2 mM Triton X-100. b Faradaic efficiency measurements of the first 10 h of the CA. The red dots represent the average amount of H2 measured at different times via gas chromatography, and the black dotted curve is the amount of H2 calculated from the photocurrent over time. c LSV curves of the photocathode before (red curve) and after 10 hours (blue curve) of CA under AM 1.5 G one-sun illumination and dark (black curve) conditions. d Nyquist plots of the photocathode before (red curve) and after 10 h (blue curve) of CA under AM 1.5 G one-sun illumination.