Higher hydrogen production by photocatalytic water splitting using a hollow tubular graphitic carbon nitride-zinc telluride composite

摘要

Abstract Energy demand and pollution due to urbanization and industrialization are calling for clean energies such as dihydrogen (H2) obtained by water splitting. For that, zinc telluride is a promising semiconductor having a narrow bandgap that can absorb a large amount of visible light and promotes the separation of charge carriers. Here, we prepared a 1D hollow tubular graphitic carbon nitride (g-C3N4) composite (h-CN) by a precipitation using melamine as a precursor. Results show that composite produces higher yields of dihydrogen, of 11,188?μmol?g?1?h?1, than with ZnTe, of 8331?μmol?g?1?h?1, and with h-CN, of 1012?μmol?g?1?h?1. Furthermore, the new modified heterojunction displays quantum efficiency of about 17.1% at 420?nm, which is much higher than for h-CN, of 0.87%, and for ZnTe, of 7.29%. Higher performances are explained by reducing the charge recombination and increasing the transfer of electrons by creating a strong p-n heterojunction. An advantage of the new photocatalyst is that it does not require an expensive noble metal.