Details

Autor(en) / Beteiligte

• Wang, Ke
• Du, Hongfang
• He, Song
• Liu, Lei
• Yang, Kai
• Sun, Jinmeng
• Liu, Yuhang
• Du, Zhuzhu
• Xie, Linghai
• Ai, Wei
• Huang, Wei

Titel

Kinetically Controlled, Scalable Synthesis of γ‐FeOOH Nanosheet Arrays on Nickel Foam toward Efficient Oxygen Evolution: The Key Role of In‐Situ‐Generated γ‐NiOOH

Ist Teil von

• Advanced materials (Weinheim), 2021-03, Vol.33 (11), p.e2005587-n/a

Ort / Verlag

Germany: Wiley Subscription Services, Inc

Erscheinungsjahr

2021

Quelle

Wiley-Blackwell Journals

Beschreibungen/Notizen

• Layered γ‐type iron oxyhydroxide (γ‐FeOOH) is a promising material for various applications; however, its sheet‐shaped structure often suffers from instability that results in aggregation and leads to inferior performance. Herein, a kinetically controlled hydrolysis strategy is proposed for the scalable synthesis of γ‐FeOOH nanosheets arrays (NAs) with enhanced structural stability on diverse substrates at ambient conditions. The underlying mechanisms for the growth of γ‐FeOOH NAs associated with their structural evolution are systematically elucidated by alkalinity‐controlled synthesis and time‐dependent experiments. As a proof‐of‐concept application, γ‐FeOOH NAs are developed as electrocatalysts for the oxygen evolution reaction (OER), where the sample grown on nickel foam (NF) exhibits superior performance of high catalytic current density, small Tafel slope, and exceptional durability, which is among the top level of FeOOH‐based electrocatalysts. Density functional theory calculations suggest that γ‐NiOOH in situ generated from the electrooxidation of NF would induce charge accumulation on the Fe sites of γ‐FeOOH NAs, leading to enhanced OER intermediates adsorption for water splitting. This work affords a new technique to rationally design and synthesize γ‐FeOOH NAs for various applications. The controllable and scalable synthesis of γ‐iron oxyhydroxide (γ‐FeOOH) nanosheets arrays (NAs) on diverse substrates is achieved via one‐step hydrolysis of K2FeO4 in NaOH solution under ambient conditions, where NaOH decides the hydrolysis pathway and kinetics of K2FeO4. Benefiting from the optimized nanostructure and electrooxidation‐generated γ‐NiOOH, the γ‐FeOOH NAs on nickel foam system exhibits excellent catalytic performance for the oxygen evolution reaction.