Ruthenium-Doped Cobalt-Chromium Layered Double Hydroxides for Enhancing Oxygen Evolution through Regulating Charge Transfer

Chenlong Dong; Xilin Zhang; Jie Xu; Rui Si; Jun Sheng; Jun Luo; Shaoning Zhang; Wujie Dong; Guobao Li; Weichao Wang; Fuqiang Huang

doi:10.1002/smll.201905328

Ruthenium-Doped Cobalt-Chromium Layered Double Hydroxides for Enhancing Oxygen Evolution through Regulating Charge Transfer

Small. 2020 Feb;16(5):e1905328. doi: 10.1002/smll.201905328. Epub 2020 Jan 10.

Authors

Chenlong Dong¹, Xilin Zhang^{2

3}, Jie Xu⁴, Rui Si⁵, Jun Sheng¹, Jun Luo⁴, Shaoning Zhang⁶, Wujie Dong⁶, Guobao Li¹, Weichao Wang^{2

3}, Fuqiang Huang^{1

6}

Affiliations

¹ State Key Laboratory of Rare Earth Materials Chemistry and Applications, College of Chemistry and Molecular Engineering, Peking University, Beijing, 100871, P. R. China.
² School of Physics, Henan Normal University, Xinxiang, 453007, P. R. China.
³ Department of Electronics, National Institute for Advanced Materials, Renewable Energy Conversion and Storage Center, Tianjin Key Laboratory of Photo-Electronic Thin Film Device and Technology, Nankai University, Tianjin, 300071, P. R. China.
⁴ Center for Electron Microscopy and Tianjin Key Lab of Advanced Functional Porous Materials, Institute for New Energy Materials & Low-Carbon Technologies, School of Materials Science and Engineering, Tianjin University of Technology, Tianjin, 300384, P. R. China.
⁵ Shanghai Synchrotron Radiation Facility, Shanghai Institute of Applied Physics, Chinese Academy of Sciences, Shanghai, 201204, P. R. China.
⁶ CAS Key Laboratory of Materials for Energy Conversion and State Key Laboratory of High Performance Ceramics and Superfine Microstructure, Shanghai Institute of Ceramics, Chinese Academy of Sciences, Shanghai, 200050, P. R. China.

PMID: 31922697
DOI: 10.1002/smll.201905328

Abstract

Exploring the origin of transition metal (TM) lattice-doped layered double hydroxides (LDHs) toward the oxygen evolution reaction (OER) plays a crucial role in engineering efficient electrocatalysts. Without understanding the physics behind the TM-induced catalytic enhancements, it would be challenging to design the next generation of electrocatalysts. Herein, single Ru atoms are introduced into a CoCr LDHs lattice to improve activity. In 0.1 m KOH, CoCrRu LDHs require only 290 mV overpotential to drive to 10 mA cm^-2 and show a Tafel slope of 56.12 mV dec^-1 . Electronic structure analyses based on density functional theory confirm that promoted OER activity originates from synergetic charge transfer among Ru, Cr, and Co elements. Specifically, Ru dopants can downshift d states of Co and enhance electron donation of Cr to oxygenates, which essentially breaks the scaling relation and achieves higher activity. This work provides insights into how single atomic Ru dopant tunes the electronic structures of its neighbor's active site Co and thus increases OER activities.

Keywords: charge transfer; lattice doping; layered double hydroxides; oxygen evolution reaction; single atoms.

Abstract

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