Construction of a MoxC/Ni Network Electrode with Low Overpotential for Hydrogen Generation

• Published in: ChemCatChem Vol. 6; no. 7; pp. 2059 - 2064
• Main Authors: Zhang, Jian, Meng, Xin, Zhao, Jianghong, Zhu, Zhenping
• Format: Journal Article
• Language: English
• Published: Weinheim WILEY-VCH Verlag 01.07.2014; WILEY‐VCH Verlag; Wiley Subscription Services, Inc
• Subjects: electrocatalysts; Electrodes; hydrogen evolution; molybdenum carbide; nickel; Solar energy; water splitting
• ISSN: 1867-3880; 1867-3899
• DOI: 10.1002/cctc.201402000

The integration of commercial photovoltaic devices and electrocatalysts has attracted considerable interest to realize the conversion of solar power to renewable hydrogen energy. However, a noble metal electrocatalyst (Pt) is too expensive and rare, which inspires the development of efficient and economical catalytic electrodes. Herein, we have fabricated a 3 D MoxC/Ni network through the carbonization of a polyaniline–Mo7O24 precursor, which was electrochemically deposited on Ni foam in advance. If the 3 D MoxC/Ni network is used as a catalytic electrode for the hydrogen evolution reaction (HER), a low onset potential of approximately 44 mV for driving 1 mA cm−2 of current density and a Tafel slope of approximately 49 mV decade−1 (overpotential η=50–60 mV) are obtained. Moreover, the apparent exchange current density reaches approximately 0.1 mA cm−2. After a long‐term HER test at η=100 mV or 500 CV sweeps, no deactivation is observed. This excellent electrocatalytic performance of the 3 D MoxC/Ni network promotes it as a promising earth‐abundant HER electrode. A remarkable breakthrough: We develop a facile strategy to fabricate a 3 D MoxC/Ni network with a low onset potential of approximately 44 mV for driving 1 mA cm−2 of current density and a high apparent exchange current density of approximately 0.15 mA cm−2. Moreover, the 3 D MoxC/Ni electrode possesses excellent hydrogen evolution reaction durability.