Pseudocapacitive Ni‐Co‐Fe Hydroxides/N‐Doped Carbon Nanoplates‐Based Electrocatalyst for Efficient Oxygen Evolution

• Published in: Small (Weinheim an der Bergstrasse, Germany) Vol. 14; no. 34; pp. e1801878 - n/a
• Main Authors: Liu, Wu‐Jun, Hu, Xiao, Li, Hong‐Chao, Yu, Han‐Qing
• Format: Journal Article
• Language: English
• Published: Germany Wiley Subscription Services, Inc 01.08.2018
• Subjects: Carbon; Catalysis; Catalysts; Catalytic activity; Cobalt; Electrocatalysts; Flux density; Hydrogels; Hydroxides; Iron; Modular structures; Nanotechnology; Nickel; Ni‐Co‐Fe hydroxides; N‐doped carbon; oxygen evolution reaction; Oxygen evolution reactions; pseudocapacitive; Synthesis; Transition metal oxides; oxygen evolution reaction; pseudocapacitive; Ni-Co-Fe hydroxides; electrocatalysts; N-doped carbon
• ISSN: 1613-6810; 1613-6829; 1613-6829
• DOI: 10.1002/smll.201801878

The oxygen evolution reaction (OER) catalytic activity of a transition metal oxides/hydroxides based electrocatalyst is related to its pseudocapacitance at potentials lower than the OER standard potential. Thus, a well‐defined pseudocapacitance could be a great supplement to boost OER. Herein, a highly pseudocapacitive Ni‐Fe‐Co hydroxides/N‐doped carbon nanoplates (NiCoFe‐NC)‐based electrocatalyst is synthesized using a facile one‐pot solvothermal approach. The NiCoFe‐NC has a great pseudocapacitive performance with 1849 F g−1 specific capacitance and 31.5 Wh kg−1 energy density. This material also exhibits an excellent OER catalytic activity comparable to the benchmark RuO2 catalysts (an initiating overpotential of 160 mV and delivering 10 mA cm−2 current density at 250 mV, with a Tafel slope of 31 mV dec−1). The catalytic performance of the optimized NiCoFe‐NC catalyst could keep 24 h. X‐ray photoelectron spectroscopy, electrochemically active surface area, and other physicochemical and electrochemical analyses reveal that its great OER catalytic activity is ascribed to the Ni‐Co hydroxides with modular 2‐Dimensional layered structure, the synergistic interactions among the Fe(III) species and Ni, Co metal centers, and the improved hydrophily endowed by the incorporation of N‐doped carbon hydrogel. This work might provide a useful and general strategy to design and synthesize high‐performance metal (hydr)oxides OER electrocatalysts. In this work, a highly pseudocapacitive Ni‐Fe‐Co hydroxides/N‐doped carbon nanoplates (NiCoFe‐NC)‐based electrocatalyst is synthesized via a facile one‐pot solvothermal approach. The as‐synthesized NiCoFe‐NC has an excellent pseudocapacitive performance, leading to high oxygen evolution reaction catalytic activity with an overpotential of 160 mV and delivering 10 mA cm−2 current density at 250 mV overpotential.