Ultrathin Co3S4 nanosheets that synergistically engineer spin states and exposed polyhedra that promote water oxidation under neutral conditions

Youwen Liu; Chong Xiao; Mengjie Lyu; Yue Lin; Weizheng Cai; Pengcheng Huang; Wei Tong; Youming Zou; Yi Xie

doi:10.1002/anie.201505320

Ultrathin Co3S4 nanosheets that synergistically engineer spin states and exposed polyhedra that promote water oxidation under neutral conditions

Angew Chem Int Ed Engl. 2015 Sep 14;54(38):11231-5. doi: 10.1002/anie.201505320. Epub 2015 Jul 31.

Authors

Youwen Liu¹, Chong Xiao², Mengjie Lyu¹, Yue Lin¹, Weizheng Cai¹, Pengcheng Huang¹, Wei Tong³, Youming Zou³, Yi Xie⁴

Affiliations

¹ Hefei National Laboratory for Physical Sciences at the Microscale, Collaborative Innovation Center of Chemistry for Energy Materials, University of Science and Technology of China, Hefei, Anhui, 230026 (P.R. China).
² Hefei National Laboratory for Physical Sciences at the Microscale, Collaborative Innovation Center of Chemistry for Energy Materials, University of Science and Technology of China, Hefei, Anhui, 230026 (P.R. China). cxiao@ustc.edu.cn.
³ High Magnetic Field Laboratory, Chinese Academy of Sciences, Hefei, Anhui, 230031 (P.R. China).
⁴ Hefei National Laboratory for Physical Sciences at the Microscale, Collaborative Innovation Center of Chemistry for Energy Materials, University of Science and Technology of China, Hefei, Anhui, 230026 (P.R. China). yxie@ustc.edu.cn.

PMID: 26235387
DOI: 10.1002/anie.201505320

Abstract

Development of efficient and affordable electrocatalysts in neutral solutions is paramount importance for the renewable energy. Herein, we report that the oxygen evolution reaction (OER) performance of Co3 S4 under neutral conditions can be enhanced by exposed octahedral planes and self-adapted spin states in atomically thin nanosheets. A HAADF image clearly confirmed that the active octahedra with Jahn-Teller distortions were exposed exclusively. Most importantly, in the atomically thin nanosheets, the spin states of Co(3+) in the octahedral self-adapt from low-spin to high-spin states. As a result, the synergistic effect endow the Co3 S4 nanosheets with superior OER performance, with exceptional low onset overpotentials of circa 0.31 V in neutral solutions, which is state-of-the-art among inorganic non-noble metal compounds.

Keywords: cobalt; exposed polyhedra; nanosheets; spin states; water oxidation.