標題: Synergistic-Effect-Controlled CoTe2/Carbon Nanotube Hybrid Material for Efficient Water Oxidation
作者: Lu, Tzu-Hsiang
Chen, Chih-Jung
Lu, Ying-Rui
Dong, Chung-Li
Liu, Ru-Shi
加速器光源科技與應用學位學程
Master and Ph.D. Program for Science and Technology of Accelrrator Light Source
公開日期: 15-Dec-2016
摘要: In anode, electrocatalytic water splitting involves oxygen evolution reaction (OER), which is a complex and sluggish reaction, and thus the efficiency to produce hydrogen is seriously limited by OER. We report that CoTe2 exhibits optimized OER activity for the first time. Multiwalled carbon nanotube (MWCNT) is utilized to support CoTe2 in generating a synergistic effect to enhance OER activity and improve stability by tuning different loading amounts of CoTe2 on CNT. In 1.0 M KOH, bare CoTe2 needed overpotential of 323 mV to produce 10 mA/ cm(2) with Tafel slope of 85.1 mV/dec, but CoTe2/carbon nanotube (CNT) with optimized loading amount of CoTe2 required only 291 mV to produce10 mA/cm(2) with Tafel slope of 44.2 mV/dec. X-ray absorption near edge structure (XANES) was applied to prove that an electron transfer from e(g) band of CoTe2 to CNT caused a synergistic effect. This electron transfer modulated the bond strength of oxygen-related intermediate species on the surface and optimized OER performance. In situ XANES was used to compare CoTe2/CNT and pristine CoTe2 during OER. It proved the transition state of CoOOH more easily existed by adding CNT in hybrid material during OER to enhance the efficiency of OER. Moreover, bare CoTe2 is unstable under OER, but the CoTe2/CNT hybrid materials exhibited improved and exceptional durability by time dependent potentiostatic electrochemical measurement for 24 h and continuous cyclic voltammetry for 1000 times. Our result suggests that this new OER electrocatalyst for OER can be applied in various water-splitting devices and can promote hydrogen economy.
URI: http://dx.doi.org/10.1021/acs.jpcc.6b10000
http://hdl.handle.net/11536/132969
ISSN: 1932-7447
DOI: 10.1021/acs.jpcc.6b10000
期刊: JOURNAL OF PHYSICAL CHEMISTRY C
Volume: 120
Issue: 49
起始頁: 28093
結束頁: 28099
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