MoSx Quantum Dot-Modified Black Silicon for Highly Efficient Photoelectrochemical Hydrogen Evolution

Nanostructured black silicon (bSi) is widely used for solar water-splitting application due to the excellent light-harvesting properties and large surface area-to-volume ratio that favors photoelectrochemical reactions. However, bSi suffers from low catalytic activity, owing to its poor charge transfer kinetics during the hydrogen evolution process. In this work, we developed a novel photoelectrode by incorporating molybdenum sulfide (MoSx) quantum dots on the surface of black silicon. The synergetic effect of MoSx and bSi significantly enhances the activity for the hydrogen evolution reaction. An onset potential of 0.255 V-RHE, a high short-circuit photocurrent density (J(sc)) of 12.2 mA.cm(-2), and a hydrogen evolution rate of 226.5 mu mol.h(-1).cm(-2) have been achieved.