Materials Engineering in Perovskite for Optimized Oxygen Evolution Electrocatalysis in Alkaline Condition. Issue 2 (16th December 2020)

• Record Type: Journal Article
• Authors: Dong, Feifei; Li, Lu; Kong, Ziqi; Xu, Xiaomin; Zhang, Yaping; Gao, Zhenghui; Dongyang, Biaokui; Ni, Meng; Liu, Quanbing; Lin, Zhan
• Is Part Of: Small. Volume 17:Issue 2(2021)
• Page Start: n/a
• Page End: n/a
• Publication Date: 2020-12-16
• Subjects: electrocatalysis -- oxygen evolution reaction -- oxygen vacancy -- perovskites -- water splitting; Nanotechnology -- Periodicals; Nanoparticles -- Periodicals; Microtechnology -- Periodicals; 620.5
• DOI: 10.1002/smll.202006638
• Languages: English
• ISSNs: 1613-6810

Abstract

Abstract: Developing robust and highly efficient electrocatalysts for oxygen evolution reaction (OER) is critical for renewable, secure, and emission‐free energy technologies. Perovskite Ba0.5 Sr0.5 Co0.8 Fe0.2 O3‐δ (BSCF) has emerged as a promising OER electrocatalyst with desirable intrinsic activity. Inspired by the factor that substituting in transition‐metal sublattice of the perovskite can further optimize the OER activity, herein, nickel‐substituted BSCF is adopted, that is, Ba0.5 Sr0.5 Co0.8‐ x Fe0.2 Ni x O3‐δ ( x = 0.05, 0.1, 0.2, denoted as BSCFN x, x = 5, 10, 20, respectively), as efficient and stable OER catalysts in alkaline solution. The phase structure, microchemistry, oxygen vacancy, and electrochemical activity of such samples are well‐investigated. Endowed with an overpotential of only 278 mV at 10 mA cm −2 and a Tafel slope of merely 47.98 mV dec −1, BSCFN20 exhibits the optimum OER activity. When constructing a two‐electrode cell with BSCFN20 as anode and Pt/C as cathode (BSCFN20||Pt/C) for water splitting, it only requires a voltage of 1.63 V to achieve 50 mA cm −2, and the BSCFN20||Pt/C remains stable within 80 h at 10 mA cm −2, superior to the state‐of‐the‐art RuO2 ||Pt/C counterpart. This work provides a feasible strategy for designing stable and highly active perovskite electrocatalysts for future energy storage and conversion. Abstract : Nickel‐substituted perovskites Ba0.5 Sr0.5 Co0.8‐ x Fe0.2 Ni x O3‐δ (BSCFN x ) are developed as highly active and durable electrocatalysts for oxygen evolution reaction (OER). BSCFN20 representing the Ni ratio of 20% exhibits the optimum OER activity. The alkaline electrolytic cell with BSCFN20 anode achieves remarkable activity and durability for water oxidation. The increased oxygen vacancies resulting from Ni substitution enables promising OER electroactivity and water splitting.