Activating the hydrogen evolution and overall water splitting performance of NiFe LDH by cation doping and plasma reduction

• Published in: Applied catalysis. B, Environmental Vol. 266; p. 118627
• Main Authors: Tang, Yuanhao, Liu, Qian, Dong, Lin, Wu, Hao Bin, Yu, Xin-Yao
• Format: Journal Article
• Language: English
• Published: Amsterdam Elsevier B.V 05-06-2020; Elsevier BV
• Subjects: Adsorption; Cations; Density functional theory; Doping; Electrocatalysts; Electron transfer; Electronic structure; Evolution; Heterostructures; Hydrogen; Hydrogen evolution reaction; Hydrogen evolution reactions; Hydroxides; Intermetallic compounds; Iron compounds; Nanoparticles; Nickel compounds; Nickel iron layered double hydroxide; Overall water splitting; Oxygen; Oxygen evolution reactions; Reduction; Splitting; Vacancies; Water splitting; Nickel iron layered double hydroxide; Hydrogen evolution reaction; Reduction; Overall water splitting; Doping
• ISSN: 0926-3373; 1873-3883
• DOI: 10.1016/j.apcatb.2020.118627

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•A novel strategy is developed to activate the HER performance of NiFe LDH.•The HER and overall water splitting performance of NiFe LDH is greatly improved.•A electrolysis cell with small voltage and long durability is fabricated.
NiFe layered double hydroxides (LDHs) have been intensively investigated as promising electrocatalysts for oxygen evolution reaction. However, their hydrogen evolution reaction (HER) and overall water splitting performance are not satisfactory. Herein, we report a facile cation doping combined with plasma reduction strategy to generate heterostructured Ni nanoparticles/V-doped NiFe LDH nanosheet array with multiple vacancies, exhibiting excellent HER performance with a small overpotential of 19 mV at 10 mA cm−2. Moreover, when evaluated as bi-functional electrocatalyst for overall water splitting, a small cell voltage (1.43 V at 10 mA cm−2) and ultralong stability (over 1000 h) are achieved. Density functional theory (DFT) calculations reveal that V-doping, oxygen vacancy (Ov), Ni vacancy (Niv), and Ni nanoparticles can effectively improve the conductivity and optimize the hydrogen adsorption, Ov, Niv, and Ni nanoparticles help to facilitate H2O adsorption and dissociation progress in HER, the V-doping and Ov can efficiently reduce the energy barrier of O* in OER, and Ni/NiFe LDH heterostructure ameliorates the electronic structure and tunes electron transfer route.