Heteroepitaxial Growth of GaP Photocathode by Hydride Vapor Phase Epitaxy for Water Splitting and CO2 Reduction

Heteroepitaxial Zn-doped p-GaP was grown on (001) GaAs, Si and (111) substrates by hydride vapor phase epitaxy for solar-driven photoelectrochemical applications of hydrogen generation water splitting CO2 reduction. Growth GaP realized through the implementation a low-temperature buffer layer, morphology crystalline quality were enhanced optimizing precursor flows pre-heating ambient substrate. The p-GaP/GaAs p-GaP/Si samples processed to photoelectrodes with an amorphous TiO2 coating reduction combination layer mesoporous tungsten phosphide catalyst splitting. P-GaP/GaAs suitable Zn-doping concentration exhibited performance comparable homoepitaxial p-GaP/GaP Degradation photocurrent in is observed PEC due high density defects arising from heteroepitaxial growth.