CuS Nanosheets Decorated with CoS₂ Nanoparticles as an Efficient Electrocatalyst for Enhanced Hydrogen Evolution at All pH Values

Abstract

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.

A High Catalytic Activity Photocatalysts Based on Porous Metal Sulfides/TiO2 Heterostructures

“…[ 60 ] For S 2p spectra, the corresponding peaks are found at 160.5 and 161.6 eV, which is assigned to the S 2p 3/2 and S 2p 1/2 of S 2− in metal sulfides. [ 61 ]…”

Multifunctional photo‐electrocatalysts of copper sulfides prepared via pulsed laser ablation in liquid: Phase formation kinetics and photo‐electrocatalytic activity

“…26 There are many recent works on Cu x S y applications in the newly emerging research fields created by the current economic and environmental issues, such as solar cells, photovoltaics, photocatalysts, photothermal agents, and electrocatalysts for the HER and CO 2 reduction reactions. [30][31][32][33][34][35][36][37][38] A few studies were performed to explore the applicability of Cu x S y for the HER and CO 2 reduction, which revealed that Cu-based materials could be used in energy storage devices and major CO 2 converters. 30,[39][40][41] In most previous works, Cu x S y was prepared by a conventional hydrothermal method, chemical bath deposition, and wet-chemical route.…”

“…In contrast, Cu 2 S does not exhibit any localized surface plasmon resonance (LSPR) 26 . There are many recent works on Cu x S y applications in the newly emerging research fields created by the current economic and environmental issues, such as solar cells, photovoltaics, photocatalysts, photothermal agents, and electrocatalysts for the HER and CO 2 reduction reactions 30‐38 . A few studies were performed to explore the applicability of Cu x S y for the HER and CO 2 reduction, which revealed that Cu‐based materials could be used in energy storage devices and major CO 2 converters 30,39‐41 …”

Porous Cobalt Sulfide Selenium Nanorods for Electrochemical Hydrogen Evolution

“…Meanwhile, the properties of electrochemical devices are closely related to the structure of materials. Therefore, in recent years, scientists have been trying to develop new techniques for synthesizing different structures such as nanoparticles, nanosheets, − nanocrystals, nanoboxes, , nanowires, and so on. Nonetheless, the performance of pure CoS 2 is still insufficient due to lack of active sites and low conductivity.…”