Fast fabrication of ultrathin CoMn LDH nanoarray as flexible electrode for water oxidation. (1st September 2018)

• Record Type: Journal Article
• Authors: Yan, Feng; Guo, Dong; Kang, Jianyu; Liu, Lina; Zhu, Chunling; Gao, Peng; Zhang, Xitian; Chen, Yujin
• Is Part Of: Electrochimica acta. Volume 283(2018)
• Page Start: 755
• Page End: 763
• Publication Date: 2018-09-01
• Subjects: Ultrathin CoMn LDH -- Electrodeposition -- Flexible electrode -- OER -- Nanosheet; Electrochemistry -- Periodicals; Electrochemistry, Industrial -- Periodicals; 541.37
• DOI: 10.1016/j.electacta.2018.06.202
• Languages: English
• ISSNs: 0013-4686

Abstract

Abstract: Electrochemical water splitting is an efficient way for large-scale production of clean hydrogen fuel. However, high overpotential is required to catalyzing oxygen evolution reaction (OER). Here we fabricate self-supported CoMn-LDH nanosheets with a thickness of approximately 1.9 nm on carbon fiber cloth through electrodeposition method within 50 s. The self-supported, binder-free anodes exhibit excellent OER performance with an overpotential of 258 mV at 10 mA cm −2 in 0.1 M KOH solution, remarkably lower than those of Co and Mn single counterparts, and the-state-of-the-art IrO2 catalyst. Furthermore, self-supported, binder-free anodes exhibit robust stability for OER with a negligible current loss even at a high current density (>370 mA cm −2 ) over 15 h. Flexible and bendable measurements indicate no obvious degradation in the OER performance of the anode even as being bended to 180°. Moreover, the water electrolysis with the CoMn-LDH/CFC as anode and Pt/C/CFC as cathode only needs a cell voltage of 1.54 V to deliver the current density of 10 mA cm −2 in 0.1 M KOH solution. Our experimental results demonstrate that the electron interaction between Mn and Co, increased electrochemical active area and decreased charge-transfer resistance contribute to the enhancement of the optimized anode in OER performance. Graphical abstract: Image 1 Highlights: Ultrathin CoMn-LDH/carbon fiber cloth flexible electrodes are synthesized. The electrodeposition time of the optimized anode is only 50 s. The electrodes exhibit remarkably enhanced OER activities in 0.1 M KOH. The electrode requires an overpotential of 258 mV at 10 mA cm −2 . The OER performance of the electrode outperforms the commercial IrO2 catalyst.