Liquid‐Crystal‐Mediated 3D Macrostructured Composite of Co/Co3O4 Embedded in Graphene: Free‐Standing Electrode for Efficient Water Splitting. (3rd March 2017)

• Record Type: Journal Article
• Authors: Islam, Md. Monirul; Faisal, Shaikh Nayeem; Akhter, Taslima; Roy, Anup Kumar; Minett, Andrew I.; Konstantinov, Konstantin; Dou, Shi Xue
• Is Part Of: Particle and particle systems characterization. Volume 34:Number 9(2017:Sep.)
• Page Start: n/a
• Page End: n/a
• Publication Date: 2017-03-03
• Subjects: electrocatalysts -- free‐standing -- hydrogen evolution -- liquid crystal graphene oxides -- oxygen evolution; Particles -- Periodicals; 620.43
• DOI: 10.1002/ppsc.201600386
• Languages: English
• ISSNs: 0934-0866

Abstract

Abstract : A free‐standing, 3D, macro/microstructured atomic‐cobalt/cobalt‐oxide–reduced‐graphene‐oxide (Co/Co3 O4 ‐Gr) composite has been developed for complete water splitting. The self‐assembled porous morphology associated with the metal/metal oxide active sites makes the whole surface of the electrode conducive toward catalyzing hydrogen and oxygen evolution in alkaline media at a low onset potential. The liquid‐crystal‐mediated free‐standing electrocatalyst shows oxygen evolution at the onset potential of 1.38 V and at the potential of 1.66 V for a current density of 10 mA cm −2 . These potentials are comparable to the corresponding values for Ru/C (1.46 and 1.62 V, respectively). In addition, the promising hydrogen evolution performance of our composite compared to Pt/C in alkaline media makes it an efficient bifunctional electrocatalyst for comprehensive water splitting, as well as provides guidance for future electrochemical energy material technologies. Abstract : The self‐assembly nature of liquid crystal graphene oxide leads the formation of free‐standing electrode of metal/metal oxide (Co/Co3 O4 ) embedded graphene. The formation of cobalt along with cobalt oxide in a 3D macro/microarchitecture graphene facilitates complete electrocatalytic water splitting through hydrogen evolution reaction as well as oxygen evolution reaction.