Controllable tuning of polymetallic Co-Ni-Ru-S-Se ultrathin nanosheets to boost electrocatalytic oxygen evolution

Abstract

Replacing precious metals in oxygen evolution reaction (OER) catalysts has broad prospects to achieve a viable water splitting system. Since the electrocatalytic OER is a four-electron transfer reaction with a very sluggish kinetic process, there is great interest in the development of inexpensive, durable, and high-efficiency OER catalysts. Herein, trimetallic Co-Ni-Ru sulfoselenide and bimetallic sulfoselenide nanosheets were designed by regulating their composition and morphology for efficient and durable OER electrocatalysis. The sheet structure has a large specific surface area to promote contact between the catalyst and electrolyte. Compared with bimetallic Co-Ni, Co-Ru, Ni-Ru, Co-Cd, and Co-Au sulfoselenide nanosheets, trimetallic Co-Ni-Ru sulfoselenide nanosheets show superior OER performance. By modulating the composition ratio of metal atoms in the Co-Ni-Ru-S-Se nanosheets (1:1:0.5:1:1), the nanosheets showed a significant OER overpotential of η = 261 mV (1.491 V versus RHE) at 10 mA cm−2, a Tafel slope of 52.2 mV dec–1 and outstanding stability after 48 h of continuous testing. For comparison, Co-Ni, Co-Ru, Ni-Ru, Co-Cd, and Co-Au bimetallic sulfoselenide nanosheets (denoted as Co-Ni-S-Se, Co-Ru-S-Se, Ni-Ru-S-Se, Co-Au-S-Se, Co-Cd-S-Se) were also tested. Density functional theory (DFT) calculations showed that appropriately doping Ru and Ni simultaneously (Co-Ni-Ru-S-Se) can increase the density of the states at the Fermi level, resulting in excellent charge density and low intermediate adsorption energy. These findings present a practical route to design 2D polymetallic nanosheets to optimize catalytic OER performance.

Construction of bimetallic FeCo–SA/DABCO nanosheets by modulating the electronic structure for improved electrocatalytic oxygen evolution

“…3a). [37][38][39][40][41] X-ray photoelectron spectroscopy (XPS) was used to verify the surface conditions and valence states of FeCo-SA/DABCO. 42 The C 1s peak at 284.8 eV was used to calibrate the binding energy location of each sample, ensuring that no binding energy alterations occurred due to charging.…”

Recent development and challenges in fuel cells and water electrolyzer reactions: an overview

“… 130 The salient feature is the well-defied ultrathin nanosheet morphological structure of the trimetallic Co–Ni–Ru–S–Se nanocomposite matrix, which was used as an important benchmark for OER catalytic activity under alkaline conditions. 131 One of the most effective approaches was used for the fabrication of a multifunctional (CoNi-N-CNT) electrocatalyst owing to its tunable atomic structure and three different active sites, for example, N-doped CNT, Ni–N–C, and CoNi alloys, respectively. These types of active sites could contribute synergetic catalytic performance in sustainable as well as clean energy technology.…”

Experimentally revealed and theoretically certified synergistic electronic interaction of V-doped CoS for facilitating the oxygen evolution reaction

“…Due to the continuous and rapid growth in global energy demands, together with increasingly serious environmental pollution problems, developing new sources of clean and renewable energy is important. 1,2 Hydrogen is considered to be an ideal substitute for traditional fossil fuels due to its high energy density and environmental friendness. 3,4 Electrocatalytic water decomposition is regarded as the most promising method for hydrogen production due to its high efficiency and high purity.…”