The synergetic effect of N, S-codoped carbon and CoOx nanodots derived from ZIF-67 as a highly efficient cocatalyst over CdS nanorods

Abstract

Earth-abundant transition metal cocatalysts are promising rare and noble metal alternatives for efficient photocatalytic hydrogen evolution. Herein, a novel composite of ZIF-67 derived CoO_x nanodots confined in a N, S co-doped graphitic nanosheet co-catalyst (CoO_x@N, S-C) was successfully constructed via a one pot carbonization process. Through loading onto photosensitizer of CdS nanorods, the obtained CoO_x@N, S-C/CdS composite exhibited an unprecedented H₂ production rate of 40.1 mmol g⁻¹ h⁻¹, which is 57, 20 and 1.7 times higher than that of CdS, N, S-C/CdS and CoO_x/CdS, respectively. It was demonstrated that the excellent photocatalytic H₂ production performance arises from the synergetic effect between the confined ultrafine CoO_x nanodots and N, S heteroatom co-doped graphitic carbon. This work shows considerable improvements over MOF derived materials as non-noble cocatalysts and provides significant motivation for new photocatalyst development for improving the conversion efficiency of solar energy to chemical fuels.