The design and fabrication of eco-friendly, highly efficient, and non-noble-metal-based catalysts are demanding challenges in energy-conversion technologies. Herein, we successfully synthesized CuS nanosheets decorated with CoS2 nanoparticles through a facile route. The optimized 3% CoS2-7% CuS catalysts exhibited remarkable electrocatalytic performance, with excellent cyclic stability at all pH values for the hydrogen evolution reaction (HER). They exhibited lower Tafel slopes (46, 52, and 59 mV dec–1) and smaller overpotentials (62, 85, and 106 mV) at 10 mA cm–2 in 0.5 M H2SO4, 1 M KOH, and 0.5 phosphate buffer aqueous solutions, respectively, than other CoS2/CuS, pure CoS2, and pure CuS catalysts. We attribute their high electrocatalytic performance to their unique heterostructure and the synergistic effects between the constituent metal sulfides that provides a large interfacial contact area, numerous charge-transfer pathways, as well as abundant surface reaction active sites, enhancing the charge-carrier transfer during the HER activity.

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Porous metal sulfides/TiO2 (P‐MST) photocatalysts are successfully prepared via a low‐cost strategy. It is found that the P‐MST possesses a high crystallinity with average pore size of ≈500 nm, which greatly enhances the structural stability as well as catalytic activity. The catalytic properties of the P‐MST are examined by monitoring the degradation of rhodamine B (RhB) under visible‐light irradiation. Particularly, the optimized 7% Bi2S3–CdS–MoS2–TiO2 heterostructures exhibit a remarkable catalytic performance (i.e., the degradation of RhB of ≈98.9%) and long‐term cyclic stability (i.e., the catalytic activity of ≈91.7% even after 30 cyclic test), compared with that of other P‐MST heterostructures. The exceptional catalytic performance may be ascribed to the following benefits: i) the porous structure supplies ample carrier charge transfer channels and lots of surface reaction sites; and ii) the suitable amount of metal sulfides grown on TiO2 have contributed to significant improvement of the electrical conductivity and the light absorption capability.