Issue 23, 2021

Yolk–shell structured CoSe2/C nanospheres as multifunctional anode materials for both full/half sodium-ion and full/half potassium-ion batteries

Abstract

Transition metal selenides (TMSs) are suitable for SIBs and PIBs owing to their satisfactory theoretical capacity and superior electrical conductivity. However, the large radius of Na+/K+ easily leads to sluggish kinetics and poor conductivity, which hinder the development of SIBs and PIBs. Structure design is an effective method to solve these obstacles. In this study, Co2+ ions combined with glycerol molecules to form self-assembled nanospheres at first, and then they were in situ converted into CoSe2 nanoparticles embedded in a carbon matrix during the selenization process. This structure has three-dimensional ion diffusion channels that can effectively hamper the aggregation of metal compound nanoparticles. Meanwhile, the CoSe2/C of the yolk–shell structure and a large number of pores help alleviate volume expansion and facilitate electrolyte wettability. These structural advantages of CoSe2/C endow it with remarkable electrochemical performances for full/half SIBs and full/half PIBs. The obtained CoSe2/C exhibits superior stability and excellent performance (312.1 mA h g−1 at 4 A g−1 after 1600 cycles) for SIBs. When it is used as an anode material for PIBs, 369.2 mA h g−1 can be retained after 200 cycles at 50 mA g−1 and 248.1 mA h g−1 can be retained after 200 cycles at 500 mA g−1; in addition, CoSe2/C also shows superior rate capacity (186.4 mA h g−1 at 1000 mA g−1). A series of ex situ XRD measurements were adapted to explore the possible conversion mechanism of CoSe2/C as the anode for PIBs. It is worth noting that the full-cell of CoSe2/C//Na3V2(PO4)3@rGO for SIBs and the full-cell of CoSe2/C//PTCDA-450 for PIBs were successfully assembled. The relationship between the structure and performance of CoSe2/C was investigated through density functional theory (DFT).

Graphical abstract: Yolk–shell structured CoSe2/C nanospheres as multifunctional anode materials for both full/half sodium-ion and full/half potassium-ion batteries

Supplementary files

Article information

Article type
Paper
Submitted
24 פבר 2021
Accepted
30 אפר 2021
First published
30 אפר 2021

Nanoscale, 2021,13, 10385-10392

Yolk–shell structured CoSe2/C nanospheres as multifunctional anode materials for both full/half sodium-ion and full/half potassium-ion batteries

X. Sun, S. Zeng, R. Man, L. Wang, B. Zhang, F. Tian, Y. Qian and L. Xu, Nanoscale, 2021, 13, 10385 DOI: 10.1039/D1NR01227D

To request permission to reproduce material from this article, please go to the Copyright Clearance Center request page.

If you are an author contributing to an RSC publication, you do not need to request permission provided correct acknowledgement is given.

If you are the author of this article, you do not need to request permission to reproduce figures and diagrams provided correct acknowledgement is given. If you want to reproduce the whole article in a third-party publication (excluding your thesis/dissertation for which permission is not required) please go to the Copyright Clearance Center request page.

Read more about how to correctly acknowledge RSC content.

Social activity

Spotlight

Advertisements