A novel flower-like architecture of FeCo@NC-functionalized ultra-thin carbon nanosheets as a highly efficient 3D bifunctional electrocatalyst for full water splitting. Issue 11 (24th February 2017)

• Record Type: Journal Article
• Authors: Li, Mian; Liu, Tingting; Bo, Xiangjie; Zhou, Ming; Guo, Liping
• Is Part Of: Journal of materials chemistry. Volume 5:Issue 11(2017)
• Page Start: 5413
• Page End: 5425
• Publication Date: 2017-02-24
• Subjects: Materials -- Research -- Periodicals; Chemistry, Analytic -- Periodicals; Environmental sciences -- Research -- Periodicals; 543.0284
• DOI: 10.1039/c6ta09976a
• Languages: English
• ISSNs: 2050-7488

Abstract

Abstract : A novel three-dimensional hierarchically meso/macroporous flower-like architecture of ultra-thin N-doped carbon nanosheets with fine FeCo@NC core–shell units dispersed on their surfaces can efficiently catalyze water splitting. Abstract : A novel three-dimensional (3D) hierarchically meso/macroporous flower-like architecture of ultra-thin N-doped carbon nanosheets (NCNS) with fine FeCo@NC core–shell units dispersed on their surfaces (denoted as FeCo@NC/NCNS) is reported as an efficient catalyst for two key electrode processes ( i.e. the oxygen evolution reaction (OER) and hydrogen evolution reaction (HER)) in the development of sustainable energy conversion systems. Upon optimization of the dosages of Fe/Co sources and calcination temperature, the optimal Fe0.5 Co0.5 @NC/NCNS-800 sample exhibits high activity with a potential of 1.5 V vs. reversible hydrogen electrode (RHE) to achieve a current density of 10 mA cm −2 for the OER in 1.0 M KOH, which even surpassed that of commercial RuO2 . Moreover, as an HER electrocatalyst in 1.0 M KOH, Fe0.5 Co0.5 @NC/NCNS-800 just requires a low overpotential of 150 mV to achieve 10 mA cm −2 with an onset potential of −63 mV. All these results highlight the synergistic effects of the 3D macroporous channels of the flower-like architecture, 2D mesoporous CNSs, high specific surface area, fine FeCo@NC core–shell units, and various active centers for boosting the OER/HER catalytic activities, defining the Fe0.5 Co0.5 @NC/NCNS as one of the best non-precious metal-based carbonaceous electrocatalysts for oxygen/hydrogen-based electrocatalysis. More importantly, when Fe0.5 Co0.5 @NC/NCNS was used as positive and negative electrodes in a two-electrode system for overall water splitting, it just required a cell voltage of 1.60 V to achieve ∼10 mA cm −2, which opens a new possibility for the construction of novel water splitting devices. We also believe that our present synthetic strategy can encourage further research for the development of other 3D hierarchically meso/macroporous noble-metal-free catalysts for sensors, batteries, and various other renewable energy applications without any tedious steps or templates.