Issue 12, 2017

Intrinsic conductivity optimization of bi-metallic nickel cobalt selenides toward superior-rate Na-ion storage

Abstract

Enhancing the conductivity of electrode materials is critically important for improving the high-rate performance of Na-ion batteries (NIBs). Herein, we report a multifaceted strategy for optimizing the conductivity and electrochemical properties of nickel cobalt selenides via the combination of fine component regulation and C coating. The electrical conductivity of C@Ni0.33Co0.67Se2/C nanofiber (CNF) (Co0.67) hybrids achieved in this study was 0.3733 S mm−1, a conductivity five-fold higher than that of selenides with a Ni/Co ratio of 2 : 1. Coupled with desirable three-dimensional (3D) nanobrush morphology and the 1D conducting path of CNFs, the Co0.67 electrode achieved a superior rate performance of 413.1 mA h g−1, even at 2 A g−1. Furthermore, the Co0.67 electrode exhibited an impressive cycling performance of 499 mA h g−1 after 100 cycles (exhibiting an 89.5% capacity retention of the second cycle). Finally, electrochemical impedance spectroscopy (EIS) and cyclic voltammetry analysis at different sweep rates were conducted to demonstrate the Co0.67 electrode's fast charge/ion transport ability and increased electrode kinetics.

Graphical abstract: Intrinsic conductivity optimization of bi-metallic nickel cobalt selenides toward superior-rate Na-ion storage

Supplementary files

Article information

Article type
Research Article
Submitted
12 sep 2017
Accepted
18 okt 2017
First published
19 okt 2017

Mater. Chem. Front., 2017,1, 2656-2663

Intrinsic conductivity optimization of bi-metallic nickel cobalt selenides toward superior-rate Na-ion storage

C. Wu, Y. Wei, Q. Lian, C. Cui, W. Wei, L. Chen and C. Li, Mater. Chem. Front., 2017, 1, 2656 DOI: 10.1039/C7QM00419B

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