Lollipop-shaped Co9S8/CdS nanocomposite derived from zeolitic imidazolate framework-67 for the photocatalytic hydrogen production

The unlimited consumption of traditional fossil fuels prompted an urgent need for the new H2 production strategies to provide green and sustainable energy resources. In this context, Co9S8 has emerged as a potent photocatalyst due to its narrow bandgap. Herein, we describe the synthesis of a recyclable lollipop-shaped Co9S8/CdS nanocomposite via direct annealing of zeolitic imidazolate framework-67 (ZIF-67) and CdS, as the template and sulfur source, respectively. The close contact of these two materials promotes the electron transfer and enhances the number of active sites toward the desired redox reaction. The special structure of Co9S8/CdS results in a high photocatalytic H2 production rate of 1852 μmol h−1 g−1 under visible-light illumination, which is ~200 times higher than that of pure ZIF-67 and Co9S8. Therefore, this study provides a new method for the preparation of Co9S8 that concomitantly improves the photocatalytic performance of pure ZIF-67 in the H2 production technology.