In Situ Fabrication of Mn-Doped NiMoO4 Rod-like Arrays as High Performance OER Electrocatalyst

Abstract

The slow kinetics of the oxygen evolution reaction (OER) is one of the significant reasons limiting the development of electrochemical hydrolysis. Doping metallic elements and building layered structures have been considered effective strategies for improving the electrocatalytic performance of the materials. Herein, we report flower-like nanosheet arrays of Mn-doped-NiMoO4/NF (where NF is nickel foam) on nickel foam by a two-step hydrothermal method and a one-step calcination method. The doping manganese metal ion not only modulated the morphologies of the nickel nanosheet but also altered the electronic structure of the nickel center, which could be the result of superior electrocatalytic performance. The Mn-doped-NiMoO4/NF electrocatalysts obtained at the optimum reaction time and the optimum Mn doping showed excellent OER activity, requiring overpotentials of 236 mV and 309 mV to drive 10 mA cm−2 (62 mV lower than the pure NiMoO4/NF) and 50 mA cm−2 current densities, respectively. Furthermore, the high catalytic activity was maintained after continuous operation at a current density of 10 mA cm−2 of 76 h in 1 M KOH. This work provides a new method to construct a high-efficiency, low-cost, stable transition metal electrocatalyst for OER electrocatalysts by using a heteroatom doping strategy.

Investigating the Corrosion Resistance of Different SiC Crystal Types: From Energy Sectors to Advanced Applications

“…In the chemical industry, many reaction processes are required to be conducted under high-temperature, high-pressure, or strongly corrosive conditions. Silicon carbide, because of its exceptional chemical stability, high-temperature resilience, and excellent thermal conductivity, emerges as an ideal material for manufacturing chemical reactors. − SiC reactors are capable of handling highly corrosive chemicals such as strong acids and bases, as widely applied in the production of silicates, fertilizers, and dyes and in the refining and petrochemical industries. Compared to traditional materials, SiC reactors provide higher thermal efficiency, reduce energy consumption, and, due to their outstanding corrosion resistance, significantly lower maintenance costs and downtime.…”

Application of changing the valence state of metals through the reaction time for efficient oxygen evolution reaction

“…[4][5][6] Different from the HER, it is known that the OER process encounters significant kinetic hindrance as it involves a four-electron process. 7 Numerous studies have demonstrated that Ir-based and Rubased catalysts are excellent OER catalysts and can effectively enhance the catalytic activity in the OER. 8 However, as noble metals, the scarcity and high price of Ir and Ru seriously restrict their widespread use.…”