Formation of Mo-Polydopamine Hollow Spheres and Their Conversions to MoO2 /C and Mo2 C/C for Efficient Electrochemical Energy Storage and Catalyst

Chunli Wang; Lianshan Sun; Feifei Zhang; Xuxu Wang; Qujiang Sun; Yong Cheng; Limin Wang

doi:10.1002/smll.201701246

Formation of Mo-Polydopamine Hollow Spheres and Their Conversions to MoO₂ /C and Mo₂ C/C for Efficient Electrochemical Energy Storage and Catalyst

Small. 2017 Aug;13(32). doi: 10.1002/smll.201701246. Epub 2017 Jul 10.

Authors

Chunli Wang^{1

2}, Lianshan Sun¹, Feifei Zhang¹, Xuxu Wang^{1

2}, Qujiang Sun¹, Yong Cheng¹, Limin Wang¹

Affiliations

¹ State Key Laboratory of Rare Earth Resource Utilization, Changchun Institute of Applied Chemistry, Chinese Academy of Sciences, Changchun, 130022, P. R. China.
² University of Science and Technology of China, Hefei, 230026, P. R. China.

PMID: 28692790
DOI: 10.1002/smll.201701246

Abstract

Highly uniform hierarchical Mo-polydopamine hollow spheres are synthesized for the first time through a liquid-phase reaction under ambient temperature. A self-assembly mechanism of the hollow structure of Mo-polydopamine precursor is discussed in detail, and a determined theory is proposed in a water-in-oil system. Via different annealing process, these precursors can be converted into hierarchical hollow MoO₂ /C and Mo₂ C/C composites without any distortion in shape. Owing to the well-organized structure and nanosize particle embedding, the as-prepared hollow spheres exhibit appealing performance both as the anode material for lithium-ion batteries and as the catalyst for hydrogen evolution reaction (HER). Accordingly, MoO₂ /C delivers a high reversible capacity of 940 mAh g^-1 at 0.1 A g^-1 and 775 mAh g^-1 at 1 A g^-1 with good rate capability and long cycle performance. Moreover, Mo₂ C/C also exhibits an enhanced electrocatalytic performance with a low overpotential for HER in both acidic and alkaline conditions, as well as remarkable stability.

Keywords: Li-ion battery; hydrogen evolution reaction; molybdenum carbide; molybdenum dioxide; polydopamine.

Publication types

Research Support, Non-U.S. Gov't