High-Performance MoP-Mo₂C/C Heterogeneous Nanoparticle Catalysts for Alkaline Hydrogen Evolution and Oxidation Reactions

Abstract

The slow kinetics of the alkaline hydrogen evolution reaction (HER) and oxidation reaction (HOR) must be upgraded to achieve a renewable hydrogen cycle. Transition metal phosphides and transition metal carbides exhibit excellent activity toward diverse catalytic reactions. The synthesis of MoP-Mo2C heterogeneous nanoparticles coated with a porous carbon network (MoP-Mo2C/C) via a one-step heat treatment was reported, which exhibited a low overpotential at 10 mA cm–2 (102.1 mV), low Tafel slope (53.1 mV dec–1), and excellent stability (96 h) for the HER. In addition, MoP-Mo2C/C exhibited excellent catalytic performance toward the HOR, with an exchange current density of 1.40 mA cm–2. Density functional theory simulations indicated that the electronic structure of MoP-Mo2C/C was optimized, and its Gibbs free energy was approximately zero, which is the origin of the fast reaction kinetics. This work provides a promising strategy for designing high-performance bifunctional electrocatalysts.

Zinc-induced polycrystalline transformation of high-entropy fluorides and derived regulatory mechanisms for bifunctional oxygen electrocatalysis

“…All of these proved that the crystal interfaces of the polycrystalline particles were more likely to participate in the OER, thereby generating oxygen-containing intermediates. 84…”

“…All of these proved that the crystal interfaces of the polycrystalline particles were more likely to participate in the OER, thereby generating oxygencontaining intermediates. 84 The practical application of the prepared catalysts is evaluated by assembling them into ZABs (Fig. 5f).…”

Hollow and Ultrathin Mo-Doped CoP Bamboo-Leaf Nanoarrays for pH-Universal Hydrogen Evolution

“…Nowadays, the widespread use of fossil energy not only occasions nonrenewable energy shortage but also leads to serious environmental pollution and unsustainable economic development. − In the cause of facilitating the continuable progress of the global economy, it is exigent to exploit reproducible clean energy and substitute fossil energy. − Hydrogen is deemed to be a desired replacement due to its environmental friendliness and high energy density. , Noble metal-based electrocatalysts appear to have outstanding activity to produce hydrogen for the HER, but their low reserve and high cost prevent actual application. − Consequently, it is still imperative to utilize nonprecious metal hydrogen evolution substances with ample sources, low price, supernal activity, and stability. , In recent years, transition metal-based materials are being widely explored, such as sulfides, , nitrides, , oxides, − and phosphides, , as preponderant HER electrocatalysts, thanks to their advantages of economical efficiency and environmental protection. Among them, transition metal phosphides (TMPs) have attracted much attention because of their low Gibbs adsorption energy. , In particular, cobalt-based phosphides possess obvious catalytic activity and durability. , In order to further improve the electrocatalytic activity, rational metal doping has been demonstrated to be a practical method. , Dopant atom substitution is finely acknowledged as an efficient tactic to ameliorate catalytic properties on account of the fact that the foreign atom can optimize the electronic structure of catalysts and the adsorption energy of intermediates. − As a common n-type dopant, Mo has the peculiarity of a large atomic radius and strong electronegativity compared with Co.…”

Sucralose with bifunctional groups as a functional additive enhancing the interfacial stability of zinc metal anodes via interfacial molecular chemistry regulation

“…Aqueous zinc ion batteries (AZIBs) hold significant promise among emerging next-generation electrochemical energy storage 1–9 and conversion 10,11 technologies due to their intrinsic safety, the earth-abundant nature of zinc resources, appropriate electrode potential (−0.76 V vs. the standard hydrogen electrode) and the high theoretical capacity (volume capacity of 5854 mA h cm −3 and gravimetric capacity of 820 mA h g −1 ) of Zn anodes. 12–15 However, Zn metal electrodes in neutral and weak acidic electrolyte aqueous environments suffer from corrosion and dendritic growth during electrochemical zinc plating/striping.…”