Extracting large photovoltages from a-SiC photocathodes with an amorphous TiO 2 front surface field layer for solar hydrogen evolution

A p–i–n junction photocathode made from 110 nm (p/i) amorphous SiC and an (n) TiO 2 top layer leads to an onset potential of +0.8 V RHE and a photocurrent density of 8.3 mA cm −2 at 0 V RHE using only earth abundant materials.