Dinh Khang Ngoc, Zheng Penglun, Dai Zhengfei, Zhang Yu, Dangol Raksha, Zheng Yun, Li Bing, Zong Yun, Yan Qingyu
Energy Research Institute @ NTU (ERI@N), Interdisciplinary Graduate School, Nanyang Technological University, Singapore, 637553, Singapore.
School of Materials Science and Engineering, Nanyang Technological University, Singapore, 639798, Singapore.
Small. 2018 Feb;14(8). doi: 10.1002/smll.201703257. Epub 2017 Dec 27.
Herein, the hydrothermal synthesis of porous ultrathin ternary NiFeV layer double hydroxides (LDHs) nanosheets grown on Nickel foam (NF) substrate as a highly efficient electrode toward overall water splitting in alkaline media is reported. The lateral size of the nanosheets is about a few hundreds of nanometers with the thickness of ≈10 nm. Among all molar ratios investigated, the Ni Fe V -LDHs/NF electrode depicts the optimized performance. It displays an excellent catalytic activity with a modest overpotential of 231 mV for the oxygen evolution reaction (OER) and 125 mV for the hydrogen evolution reaction (HER) in 1.0 m KOH electrolyte. Its exceptional activity is further shown in its small Tafel slope of 39.4 and 62.0 mV dec for OER and HER, respectively. More importantly, remarkable durability and stability are also observed. When used for overall water splitting, the Ni Fe V -LDHs/NF electrodes require a voltage of only 1.591 V to reach 10 mA cm in alkaline solution. These outstanding performances are mainly attributed to the synergistic effect of the ternary metal system that boosts the intrinsic catalytic activity and active surface area. This work explores a promising way to achieve the optimal inexpensive Ni-based hydroxide electrocatalyst for overall water splitting.
本文报道了在泡沫镍（NF）基底上通过水热合成法制备多孔超薄三元镍铁钒层状双氢氧化物（LDHs）纳米片，作为在碱性介质中用于全水分裂的高效电极。纳米片的横向尺寸约为几百纳米，厚度约为10nm。在所研究的所有摩尔比中，Ni Fe V -LDHs/NF电极表现出最佳性能。在1.0 m KOH电解液中，它对析氧反应（OER）表现出优异的催化活性，过电位适中，为231 mV，对析氢反应（HER）的过电位为125 mV。其卓越的活性还体现在OER和HER的塔菲尔斜率分别为39.4和62.0 mV dec。更重要的是，还观察到了显著的耐久性和稳定性。当用于全水分裂时，Ni Fe V -LDHs/NF电极在碱性溶液中仅需1.591 V的电压即可达到10 mA cm。这些优异的性能主要归因于三元金属体系的协同效应，该效应提高了本征催化活性和活性表面积。这项工作探索了一种有前景的方法，以实现用于全水分裂的最佳廉价镍基氢氧化物电催化剂。
