Engineering Bimetallic NiFe‐Based Hydroxides/Selenides Heterostructure Nanosheet Arrays for Highly‐Efficient Oxygen Evolution Reaction. Issue 7 (27th January 2021)

• Record Type: Journal Article
• Authors: Liu, Caichi; Han, Yu; Yao, Libing; Liang, Limin; He, Jiayin; Hao, Qiuyan; Zhang, Jun; Li, Ying; Liu, Hui
• Is Part Of: Small. Volume 17:Issue 7(2021)
• Page Start: n/a
• Page End: n/a
• Publication Date: 2021-01-27
• Subjects: bimetallic heterostructure -- (Ni, Fe)Se 2 -- NiFe(OH)x/(Ni, Fe) -- oxygen evolution -- theoretical calculation; Nanotechnology -- Periodicals; Nanoparticles -- Periodicals; Microtechnology -- Periodicals; 620.5
• DOI: 10.1002/smll.202007334
• Languages: English
• ISSNs: 1613-6810

Abstract

Abstract: Developing cost‐effective and high‐efficiency electrocatalysts toward alkaline oxygen evolution reaction (OER) is crucial for water splitting. Amorphous bimetallic NiFe‐based (oxy)hydroxides have excellent OER activity under alkaline media, but their poorly electrical conductivity impedes the further improvement of their catalytic performance. Herein, a bimetallic NiFe‐based heterostructure electrocatalyst that is composed of amorphous NiFe(OH) x and crystalline pyrite (Ni, Fe)Se2 nanosheet arrays is designed and constructed. The catalyst exhibits an outstanding OER performance, only requiring low overpotentials of 180, 220, and 230 mV at the current density of 10, 100, and 300 mA cm −2 and a low Tafel slope of 42 mV dec −1 in 1 m KOH, which is among the state‐of‐the‐art OER catalysts. Based on the experimental and theoretical results, the electronic coupling at the interface that leads to the increased electrical conductivity and the optimized adsorption free energies of the oxygen‐contained intermediates plays a crucial role in enhancing the OER activities. This work focusing on improving the OER performance via engineering amorphous‐crystalline bimetallic heterostructure may provide some inspiration for reasonably designing advanced electrocatalysts. Abstract : A novel bimetallic NiFe‐based heterostructure electrocatalyst composed of amorphous NiFe(OH) x and crystalline pyrite (Ni, Fe)Se2 nanosheet arrays is reported, which exhibits an outstanding oxygen evolution reaction activities with low overpotentials of 180, 220, and 230 mV at 10, 100, and 300 mA cm −2 . The electronic coupling at the heterostructure interface plays a key role, according to the experimental and theoretical results.