CoMo carbide/nitride from bimetallic MOF precursors for enhanced OER performance. (23rd June 2021)

• Record Type: Journal Article
• Authors: Guo, Yuanyuan; Huang, Qi; Ding, Junyang; Zhong, Li; Li, Ting-Ting; Pan, Junqing; Hu, Yue; Qian, Jinjie; Huang, Shaoming
• Is Part Of: International journal of hydrogen energy. Volume 46:Number 43(2021)
• Page Start: 22268
• Page End: 22276
• Publication Date: 2021-06-23
• Subjects: Metal-organic frameworks -- Carbon materials -- Cobalt-molybdenum carbide -- Structural transformation -- Oxygen evolution reaction; Hydrogen as fuel -- Periodicals; Hydrogène (Combustible) -- Périodiques; Hydrogen as fuel; Periodicals; 665.81
• DOI: 10.1016/j.ijhydene.2021.04.084
• Languages: English
• ISSNs: 0360-3199

Abstract

Abstract: The rational design and facile synthesis of transition metal-based catalysts supported by carbon nanomaterials with high activity, selectivity and stability remain a great challenge. Recently, the low-cost, stable and high-performance electrocatalysts for efficient oxygen evolution reaction (OER) derived from porous metal-organic framework (MOF) precursors have attracted numerous attention. Herein, a new type of CoMo carbide/nitride embedded in the flower-like carbon materials (CoMo-MI-T, MI = 2-Methylimidazole, T = 400, 500, 600, 700 °C) has been synthesized by a simple pyrolysis, in which bimetallic CoMo-MI precursors can be conveniently converted from crystalline cobalt-based MOFs of Co-MI by solvothermal reaction. The pyrolyzed CoMo-MI-T series exhibits a hierarchically porous nanostructure, high Co3 Mo3 C/N content, suitable N-doping, graphitic carbon layers as well as well-preserved flower-shaped morphology, which shows an excellent OER performance. Among them, the most optimal CoMo-MI-600 owns the small overpotential of 316 mV at 10 mA cm −2 and Tafel slope of 89.9 mV dec −1 in 1.0 M KOH solution. Meanwhile, the rotating ring-disk electrode technique is examined to verify near 4-electron transfer process for CoMo-MI-600 together with a high Faradaic efficiency of 98.7%. The well-performed CoMo-MI-600 electrocatalyst may be stemmed from the best balance of the synergistic effect of abundant multi-component, suitable electrical conductivity and large porosity. The current work will provide a new route to prepare MOF-derived bimetallic active sites in porous carbon nanomaterials with satisfactory activity and robust stability in the relevant energy applications. Graphical abstract: Image 1 Highlights: Flower-shaped bimetallic coordination polymer can be solvothermally obtained. Graphitic carbon-coated Co3 Mo3 C/N nanomaterials are obtained by pyrolysis. The synergistic effect of multi-component, electrical conductivity and porosity enhances OER.