Cheng Yi, Liu Chang, Cheng Hui-Ming, Jiang San Ping
Fuels and Energy Technology Institute, Curtin University , Perth, Western Australia 6102, Australia.
ACS Appl Mater Interfaces. 2014 Jul 9;6(13):10089-98. doi: 10.1021/am500988p. Epub 2014 Jun 23.
Oxygen evaluation reaction (OER) is the most important reaction in hydrogen production from water splitting. Here we developed metal-carbon nanotubes (M-CNTs) hybrids with high metal oxide catalyst loading synthesized by arc-discharge and chemical vapor deposition (CVD) methods as electrocatalysts for OER in alkaline solutions. The M-CNTs hybrids produced by arc-discharge (M-CNTs-Arc) and CVD (M-CNTs-CVD) exhibit a core-shell-like structure, in which metal nanoparticles (NPs) encapsulated by graphite shells are connected by carbon nanotubes (CNTs), forming M-CNTs network hybrids. M-CNTs-Arc has NiCo0.16Fe0.34 metal core and shows very high activity and superior stability for OER, achieving 100 A g(-1) at an overpotential (η) of 0.29 V and 500 A g(-1) at η = 0.37 V in 1 M KOH solution. This is probably the highest activity reported for OER in alkaline solutions. The reaction follows the first-order kinetics with respect to OH(-) concentration and Tafel slope of 34 mV dec(-1). The results demonstrate a highly efficient, scalable, and low-cost one-step synthesis method for developing highly active and stable catalysts for electrochemical water splitting in alkaline solutions.
析氧反应（OER）是水分解制氢过程中最重要的反应。在此，我们通过电弧放电和化学气相沉积（CVD）方法，开发了一种具有高金属氧化物催化剂负载量的金属-碳纳米管（M-CNTs）杂化物，作为碱性溶液中OER的电催化剂。通过电弧放电（M-CNTs-Arc）和CVD（M-CNTs-CVD）制备的M-CNTs杂化物呈现出核壳状结构，其中被石墨壳包裹的金属纳米颗粒（NPs）通过碳纳米管（CNTs）连接，形成M-CNTs网络杂化物。M-CNTs-Arc具有NiCo0.16Fe0.34金属核，对OER表现出非常高的活性和优异的稳定性，在1 M KOH溶液中，过电位（η）为0.29 V时达到100 A g(-1)，η = 0.37 V时达到500 A g(-1)。这可能是碱性溶液中OER报道的最高活性。该反应对OH(-)浓度遵循一级动力学，塔菲尔斜率为34 mV dec(-1)。结果表明，一种高效、可扩展且低成本的一步合成方法可用于开发碱性溶液中电化学水分解的高活性和稳定催化剂。
