Premium
Ultrafine Molybdenum Carbide Nanoparticles Composited with Carbon as a Highly Active Hydrogen‐Evolution Electrocatalyst
Author(s) -
Ma Ruguang,
Zhou Yao,
Chen Yongfang,
Li Pengxi,
Liu Qian,
Wang Jiacheng
Publication year - 2015
Publication title -
angewandte chemie international edition
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 5.831
H-Index - 550
eISSN - 1521-3773
pISSN - 1433-7851
DOI - 10.1002/anie.201506727
Subject(s) - tafel equation , electrocatalyst , catalysis , ammonium molybdate , materials science , molybdenum , exchange current density , chemical engineering , nanoparticle , platinum , graphene , carbide , carbon fibers , inorganic chemistry , nanotechnology , chemistry , electrochemistry , composite number , metallurgy , composite material , electrode , organic chemistry , zinc , engineering
The replacement of platinum with non‐precious‐metal electrocatalysts with high efficiency and superior stability for the hydrogen‐evolution reaction (HER) remains a great challenge. Herein, we report the one‐step synthesis of uniform, ultrafine molybdenum carbide (Mo 2 C) nanoparticles (NPs) within a carbon matrix from inexpensive starting materials (dicyanamide and ammonium molybdate). The optimized catalyst consisting of Mo 2 C NPs with sizes lower than 3 nm encapsulated by ultrathin graphene shells (ca. 1–3 layers) showed superior HER activity in acidic media, with a very low onset potential of −6 mV, a small Tafel slope of 41 mV dec −1 , and a large exchange current density of 0.179 mA cm −2 , as well as good stability during operation for 12 h. These excellent properties are similar to those of state‐of‐the‐art 20 % Pt/C and make the catalyst one of the most active acid‐stable electrocatalysts ever reported for HER.