Enhancing Distorted Metal-Organic Framework-Derived ZnO as Anode Material for Lithium Storage by the Addition of Ag2S Quantum Dots

Weixin Song; Rowena Brugge; Ioannis G Theodorou; Alvin Lukai Lim; Yuchen Yang; Tingting Zhao; Clare H Burgess; Ian D Johnson; Ainara Aguadero; Paul R Shearing; Dan J L Brett; Fang Xie; D Jason Riley

doi:10.1021/acsami.7b12661

Enhancing Distorted Metal-Organic Framework-Derived ZnO as Anode Material for Lithium Storage by the Addition of Ag₂S Quantum Dots

ACS Appl Mater Interfaces. 2017 Nov 1;9(43):37823-37831. doi: 10.1021/acsami.7b12661. Epub 2017 Oct 23.

Affiliation

¹ Department of Materials and Centre for Nanotechnology, Imperial College London , London SW7 2AZ, U.K.

PMID: 29022694
DOI: 10.1021/acsami.7b12661

Abstract

The lithium storage properties of the distorted metal-organic framework-derived nanosized ZnO@C are significantly improved by the introduction of Ag₂S quantum dots (QDs) during the processing of the material. In the thermal treatment, the Ag₂S QDs react to produce Ag nanoparticles and ZnS. The metal nanoparticles act to shorten electron pathways and improve the connectivity of the matrix, and the partial sulfidation of the ZnO surface improves the cycling stability of the material. The electrochemical properties of ZnO@C, Ag₂S QDs-treated ZnO@C, and the amorphous carbon in ZnO@C have been compared. The small weight ratio of Ag₂S QDs to ZnO@C at 1:180 shows the best performance in lithium storage. The exhibited specific capacities are improved and retained remarkably in the cycling at high current rates. At low current densities (200 mA g^-1), treatment of ZnO@C with Ag₂S QDs results in a 38% increase in the specific capacity.

Keywords: ZnO; ZnS; distorted MOFs; lithium storage; sulfidation.