Boosting ethanol oxidation over nickel oxide through construction of quasi-one-dimensional morphology and hierarchically porous structure
(1. School of Metallurgy and Environment, Central South University, Changsha 410083, China;
2. National Engineering Laboratory for High Efficiency Recovery of Refractory Nonferrous Metals Resources, Changsha 410083, China)
2. National Engineering Laboratory for High Efficiency Recovery of Refractory Nonferrous Metals Resources, Changsha 410083, China)
Abstract: Quasi-one-dimensional NiO with a hierarchically porous structure was synthesized through a facile coordination-precipitation method with the coupling effect of ammonia and a post-calcination treatment. The electrocatalytic properties of NiO fibers for the oxidation of ethanol were compared with those of NiO spheres. The results show that the fibrous NiO possesses a larger specific surface area of 140.153 m2/g and a lower electrical resistivity of 4.5×105 Ω·m, leading to an impressively superior electrocatalytic activity to spherical NiO for ethanol oxidation in alkaline media. The current decay on fibrous NiO at 0.6 V in 100-900 s was 0.00003%, which is much lower than that of spherical NiO, indicating its better stability. The unique morphology and hierarchically porous structure give the fibrous NiO great potential to be used as an anodic electrocatalyst for direct ethanol fuel cells.
Key words: hierarchically porous structure; nickel oxide; ethanol oxidation; quasi-one-dimensional morphology