Rational design W-doped Co-ZIF-9 based Co3S4 composite photocatalyst for efficient visible-light-driven photocatalytic H2 evolution

Abstract

Herein, a novel W doped Co₃S₄ composite photocatalyst was successfully prepared by MOF (metal organic framework), Co-ZIF-9, as a nanoscaled template via a hydrothermal treatment. Efficient heteroatom doping emerged a large number of joints in Co₃S₄–WS_X, providing multitudinous active sites for hydrogen catalysis. Moreover, due to these unmatched structural and compositional features, the optimized Co₃S₄–WS_X hybrid without introducing any noble metal cocatalysts in the catalytic system also displayed a brilliant performance for hydrogen evolution and prominent stability under long-term visible light irradiation. In particular, the sample of Co₃S₄–WS_X(0.6)), the amount of hydrogen evolution in the five-hour continuous light could reach up to 428.3 μmol, which was increased by 38 times compared with Co-ZIF-9. In addition, some necessary characterization such as XRD, FTIR, SEM, TEM, XPS, BET, UV-vis diffuse spectroscopy, photoelectrochemistry and PL etc. were further examed to support related results and put forward the possible reaction mechanism.