Plasma-Assisted Synthesis of NiCoP for Efficient Overall Water Splitting
Plasma-Assisted Synthesis of NiCoP for Efficient Overall Water Splitting
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DOI：
10.1021/acs.nanolett.6b03803
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发表时间：
2016-12-01
期刊：
影响因子：
10.8
通讯作者：
Alshareef, Husam N.
中科院分区：
文献类型：
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作者：
Liang, Hanfeng;Gandi, Appala N.;Alshareef, Husam N.
高效的水分解需要高活性、地球资源丰富且稳定的催化剂。单磷化物如Ni 2 P已被证明对水裂解具有活性。我们的理论分析表明，它们的性能可以进一步提高与外来金属取代，虽然很少的工作已经在这方面进行。在这里，我们首次提出了一种新型的PH 3等离子体辅助方法，将NiCo氢氧化物转化为三元NiCoP。获得的负载在Ni泡沫上的NiCoP纳米结构对析氢反应（HER）表现出上级催化活性，在碱性介质中在-10 mA cm（-2）下具有32 mV的低过电位。此外，它还能高效催化析氧反应（OER），尽管其真实的活性中心是在催化过程中原位形成的表面氧化物。具体地，在280 mV的过电位下实现10 mA cm（-2）的电流密度。这些过电位是非贵金属催化剂的最佳报道值之一。最重要的是，当用作阴极和阳极用于整体水分解时，在低至1.58 V的电池电压下实现10 mA cm（-2）的电流密度，使得NiCoP成为用于水分解的最有效的地球丰富的催化剂之一。此外，我们的新合成方法可以作为一个通用的路线，以合成各种不同的磷化物，甚至更复杂的各种应用。
Efficient water splitting requires highly active, earth-abundant, and robust catalysts. Monometallic phosphides such as Ni2P have been shown to be active toward water splitting. Our theoretical analysis has suggested that their performance can be further enhanced by substitution with extrinsic metals, though very little work has been conducted in this area. Here we present for the first time a novel PH3 plasma-assisted approach to convert NiCo hydroxides into ternary NiCoP. The obtained NiCoP nanostructure supported on Ni foam shows superior catalytic activity toward the hydrogen evolution reaction (HER) with a low overpotential of 32 mV at -10 mA cm(-2) in alkaline media. Moreover, it is also capable of catalyzing the oxygen evolution reaction (OER) with high efficiency though the real active sites are surface oxides in situ formed during the catalysis. Specifically, a current density of 10 mA cm(-2) is achieved at overpotential of 280 mV. These overpotentials are among the best reported values for non-noble metal catalysts. Most importantly, when used as both the cathode and anode for overall water splitting, a current density of 10 mA cm(-2) is achieved at a cell voltage as low as 1.58 V, making NiCoP among the most efficient earth-abundant catalysts for water splitting. Moreover, our new synthetic approach can serve as a versatile route to synthesize various bimetallic or even more complex phosphides for various applications.