Tuning the Electronic Structure of LaNiO3 through Alloying with Strontium to Enhance Oxygen Evolution Activity

Jishan Liu; Endong Jia; Le Wang; Kelsey A Stoerzinger; Hua Zhou; Chi Sin Tang; Xinmao Yin; Xu He; Eric Bousquet; Mark E Bowden; Andrew T S Wee; Scott A Chambers; Yingge Du

doi:10.1002/advs.201901073

Tuning the Electronic Structure of LaNiO₃ through Alloying with Strontium to Enhance Oxygen Evolution Activity

Adv Sci (Weinh). 2019 Aug 7;6(19):1901073. doi: 10.1002/advs.201901073. eCollection 2019 Oct 2.

Authors

Jishan Liu^{1

2

3}, Endong Jia^{3

4

5}, Le Wang³, Kelsey A Stoerzinger^{3

6}, Hua Zhou⁷, Chi Sin Tang^{8

9}, Xinmao Yin⁸, Xu He¹⁰, Eric Bousquet¹⁰, Mark E Bowden¹¹, Andrew T S Wee⁸, Scott A Chambers³, Yingge Du³

Affiliations

¹ State Key Laboratory of Functional Materials for Informatics Shanghai Institute of Microsystem and Information Technology Chinese Academy of Sciences Shanghai 200050 China.
² Center for Excellence in Superconducting Electronics Chinese Academy of Sciences Shanghai 200050 China.
³ Physical and Computational Sciences Directorate Pacific Northwest National Laboratory Richland WA 99354 USA.
⁴ The Key Laboratory of Solar Thermal Energy and Photovoltaic System Institute of Electrical Engineering Chinese Academy of Sciences Beijing 100190 China.
⁵ Department of Physics University of Chinese Academy of Sciences Beijing 100190 China.
⁶ School of Chemical Biological and Environmental Engineering Oregon State University Corvallis OR 97331 USA.
⁷ X-Ray Science Division Advanced Photon Source Argonne National Laboratory Lemont IL 60439 USA.
⁸ Department of Physics Faculty of Science National University of Singapore Singapore 117542 Singapore.
⁹ NUS Graduate School for Integrative Sciences and Engineering National University of Singapore Singapore 117456 Singapore.
¹⁰ Theoretical Materials Physics Q-MAT Cesam University of Liège B-4000 Liège Belgium.
¹¹ Environmental Molecular Sciences Laboratory Pacific Northwest National Laboratory Richland WA 99354 USA.

Abstract

The perovskite oxide LaNiO₃ is a promising oxygen electrocatalyst for renewable energy storage and conversion technologies. Here, it is shown that strontium substitution for lanthanum in coherently strained, epitaxial LaNiO₃ films (La_1- _x Sr _x NiO₃) significantly enhances the oxygen evolution reaction (OER) activity, resulting in performance at x = 0.5 comparable to the state-of-the-art catalyst Ba_0.5Sr_0.5Co_0.8Fe_0.2O_3- _δ . By combining X-ray photoemission and X-ray absorption spectroscopies with density functional theory, it is shown that an upward energy shift of the O 2p band relative to the Fermi level occurs with increasing x in La_1- _x Sr _x NiO₃. This alloying step strengthens Ni 3d-O 2p hybridization and decreases the charge transfer energy, which in turn accounts for the enhanced OER activity.

Keywords: LaNiO3; hole doping; hybridization; nickelates; oxygen evolution reaction.