Key Laboratory of Functional Inorganic Material Chemistry, Ministry of Education, Heilongjiang University, Harbin 150080, People's Republic of China.
Nanoscale. 2018 Apr 26;10(16):7619-7629. doi: 10.1039/c8nr01057a.
We have reported the synthesis of hierarchical whisker-on-sheet (HWS) NiCoP anchored on Ni foam with adjustable surface structure for efficient hydrogen evolution reaction (HER). The HWS NiCoP was obtained by controllable phosphidation of HWS Ni-Co-carbonates hydroxide precursor grown on Ni foam (NF). The experimental parameters were optimally tuned to understand the formation process of the precursor and to regulate the microstructure of the materials. The test results indicated that the HWS NiCoP/NF can produce a current density of 10 mA cm-2 (η10) at a low overpotential of 59 mV and a current density of 100 mA cm-2 (η100) at an overpotential of 220 mV for HER. Notably, upon surface activation with KOH, the HER performance of HWS NiCoP/NF could be dramatically enhanced with η10 and η100 values of 42 mV and 141 mV, respectively. The HWS NiCoP/NF showed a superior performance to NiCoP displaying other morphologies (sheets and wires etc.) The good performance of HWS NiCoP/NF should be attributed to their special whisker-on-sheet structures that are favourable for effective contact with the electrolyte. Also, hydrated metals can be formed on surface after the alkali treatment step, which is beneficial to moderate the bonding to hydrogen and thus, improve the HER activity. The present study will be indicative toward the construction of highly-efficient HER catalysts by regulating the structure of the materials.
我们报道了一种分层晶须片（HWS）NiCoP 锚定在 Ni 泡沫上的合成，具有可调的表面结构，用于高效析氢反应（HER）。HWS NiCoP 是通过在 Ni 泡沫（NF）上生长的 HWS Ni-Co-碳酸盐氢氧化物前体制备物的可控磷化获得的。实验参数被优化以了解前体的形成过程并调节材料的微观结构。测试结果表明，HWS NiCoP/NF 在低过电势 59 mV 下可产生 10 mA cm-2（η10）的电流密度，在过电势 220 mV 下可产生 100 mA cm-2（η100）的电流密度。值得注意的是，经过 KOH 表面活化后，HWS NiCoP/NF 的 HER 性能可显著增强，η10 和 η100 值分别为 42 mV 和 141 mV。HWS NiCoP/NF 的性能优于具有其他形态（薄片和线等）的 NiCoP。HWS NiCoP/NF 的良好性能应归因于其特殊的晶须片结构，有利于与电解质有效接触。此外，碱处理步骤后可以在表面形成水合金属，这有利于适度与氢结合，从而提高 HER 活性。本研究将对通过调节材料结构来构建高效 HER 催化剂具有指示意义。
