One-Step Fabrication of Monolithic Electrodes Comprising Co9 S8 Particles Supported on Cobalt Foam for Efficient and Durable Oxygen Evolution Reaction.
Dehua XiongQingqing ZhangSitaramanjaneya Mouli ThalluriJunyuan XuWei LiXiuli FuLifeng LiuPublished in: Chemistry (Weinheim an der Bergstrasse, Germany) (2017)
A very easy and cost-effective approach to the fabrication of monolithic Co9 S8 water oxidation electrodes (Co@Co9 S8 ), fabricated by one-step hydrothermal treatment of commercially available cobalt foam in the presence of thiourea, is reported. The morphology, crystal structure, microstructure, and composition of as-fabricated Co@Co9 S8 electrodes were examined by using scanning electron microscopy (SEM), powder X-ray diffractometry (XRD), transmission electron microscope (TEM), and X-ray photoelectron spectroscopy (XPS), and their electrochemical properties were investigated by cyclic voltammetry (CV), chronopotentiometry (CP), chronoamperometry (CA), and electrochemical impedance spectroscopy (EIS). When used to catalyze the oxygen evolution reaction (OER) in alkaline solution, the Co@Co9 S8 electrode with an optimal Co9 S8 loading exhibits outstanding catalytic activity, requiring a low overpotential of 350 mV to deliver an anodic current density of 10 mA cm-2 and showing fast kinetics for OER with a small Tafel slope (55 mV dec-1 ) and charge-transfer resistance (0.44 Ω cm-2 ), which outperforms many sulfide-based OER catalysts and some state-of-the-art noble metal catalysts recently reported in the literature. Importantly, the electrodes show excellent long-term stability, and are capable of operating at both a low current density and a high current density relevant to industrial water electrolysis up to 100 hours.
Keyphrases
- electron microscopy
- solid state
- reduced graphene oxide
- carbon nanotubes
- gold nanoparticles
- high resolution
- crystal structure
- molecularly imprinted
- ionic liquid
- electron transfer
- metal organic framework
- highly efficient
- systematic review
- heavy metals
- liquid chromatography
- solid phase extraction
- dual energy
- wastewater treatment
- label free
- magnetic resonance
- low cost
- hydrogen peroxide