Hollow Spherical Pd/CdS/NiS with Carrier Spatial Separation for Photocatalytic Hydrogen Generation

Abstract

Inspired by the unique properties of the three-dimensional hollow nanostructures in the field of photocatalysis, as well as the combination of co-catalyst, porous hollow spherical Pd/CdS/NiS photocatalysts are prepared by stepwise synthesis. The results show that the Schottky junction between Pd and CdS accelerates the transport of photogenerated electrons, while a p-n junction between NiS and CdS traps the photogenerated holes. As co-catalysts, the Pd nanoparticles and the NiS are loaded inside and outside the hollow CdS shell layer, respectively, which combines with the particular characteristic of the hollow structure, resulting in a spatial carrier separation effect. Under the synergy of the dual co-catalyst loading and hollow structure, the Pd/CdS/NiS has favorable stability. Its H2 production under visible light is significantly increased to 3804.6 μmol/g/h, representing 33.4 times more than that of pure CdS. The apparent quantum efficiency is 0.24% at 420 nm. A feasible bridge for the development of efficient photocatalysts is offered by this work.

Advanced Photocatalytic Nanomaterials for Energy Conversion and Environmental Remediation

“…These eleven papers were devoted to achieving high-efficiency photocatalysts by broadening the light absorption range, inhibiting the photo-induced electrons and holes recombination, and promoting the extraction of photo-induced charges for chemical reactions. The strategies include defect engineering [1], element doping [2,3], morphology manipulation [3,4], and binary and ternary composite fabrication [5][6][7][8][9][10][11]. Herein, we will provide a brief introduction to these works.…”

“…CoH x PO y nanoparticles exhibit a better hydrogen evolution reaction improvement effect on the CdIn 2 S 4 photocatalyst than Pt nanoparticles. Wang et al [11] prepared porous hollow spherical Pd/CdS/NiS, wherein the Pd and NiS co-catalysts were loaded inside and outside the hollow CdS shell layer. This special structure spatially separates the photo-generated electrons and holes, therefore remarkably increasing the photocatalytic hydrogen production rate of CdS under visible light.…”