Overall pure water splitting using one-dimensional P-doped twinned Zn0.5Cd0.5S1-x nanorods via synergetic combination of long-range ordered homojunctions and interstitial S vacancies with prolonged carrier lifetime

Abstract

Efficient spatial charge separation has been a pivotal element to improve the performance of solar water splitting. Pseudobinary ZnxCd1-xS with nano-twin structures is deemed to be one of the best pristine sulfide photocatalysts for H2 evolution, attributed to the homojunctions between parallel zinc blende/wurtzite (ZB/WZ) segments which can promote effective charge separation. One step further is to introduce heteroatom doping into the electronic structure of semiconductor to form midgap impurity level that can serves as an electron trapping site. In this contribution, we report the fabrication of one-dimensional P-doped twinned Zn0.5Cd0.5S1-x nanorods (NRs) with long-range ordered homojunction incorporated with defect-induced S vacancies. The P-doped twinned Zn0.5Cd0.5S1-x NRs demonstrated visible-light-driven pure water splitting without any sacrificial reagent and co-catalyst loading, resulting in H2 and O2 evolution rates of 0.97 and 0.42 μmol h−1, respectively. The apparent quantum yield (AQY) of H2 production was measured to be 0.15% under monochromatic 420 nm.