Metal-organic framework-derived integrated nanoarrays for overall water splitting
Metal-organic framework-derived integrated nanoarrays for overall water splitting
复制标题
用于整体水分解的金属有机框架衍生的集成纳米阵列
DOI：
10.1039/c8ta02528b
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发表时间：
2018-05-21
影响因子：
11.9
通讯作者：
Wang, John
中科院分区：
文献类型：
--
作者：
Guan, Cao;Wu, Haijun;Wang, John
在宽pH范围内用于析氢反应（HER）和析氧反应（OER）的地球丰富的电催化剂对于可持续的能量转换技术是高度期望的，但开发具有挑战性。在此，我们报告了中空CoP纳米球嵌入的碳纳米管/氮掺杂碳（NC-CNT/CoP）纳米阵列，其中纳米级Kirkendall效应产生具有丰富活性位点的少层石墨烯包覆的中空CoP纳米球。集成NC-CNT/CoP电极表现为有效的pH通用HER催化剂，并且通过原位转化，衍生材料显示出优异的OER性能。NC-CNT/CoP基电解槽在KOH、PBS和H2SO 4中分别在1.63、1.69和1.66 V的低电压下实现10 mA cm（-2）的电流密度，这与使用贵金属催化剂获得的值相似。重要的是，集成电极在宽pH范围内表现出比基准贵金属上级的稳定性。这项工作提出了一种有前途的方法，实现非贵催化剂的有效能量转换。
Earth-abundant electrocatalysts for both the hydrogen evolution reaction (HER) and oxygen evolution reaction (OER) in a wide pH range are highly desirable for sustainable energy conversion technologies, but challenging to develop. Herein, we report hollow CoP nanosphere-embedded carbon nanotube/nitrogen-doped carbon (NC-CNT/CoP) nanoarrays, in which a nanoscale Kirkendall effect generates few-layer graphene-coated hollow CoP nanospheres with abundant active sites. The integrated NC-CNT/CoP electrode behaves as an efficient pH-universal HER catalyst and, through in situ transformation, the derived materials show excellent OER performance. The NC-CNT/CoP-based electrolyzers achieve a current density of 10 mA cm(-2) at low voltages of 1.63, 1.69, and 1.66 V in KOH, PBS, and H2SO4, respectively, which are similar to the values obtained using noble metal catalysts. Importantly, the integrated electrode exhibits superior stability than that of the benchmark noble metals in a wide pH range. This work presents a promising method for achieving nonprecious catalysts for efficient energy conversion.