Core-shell coaxially structured NiCo2S4@TiO2nanorod arrays as advanced electrode for solid-state asymmetric supercapacitors

Fangya Qi; Han Li; Fan Yang; Zhipeng Sun

doi:10.1088/1361-6528/abf693

Core-shell coaxially structured NiCo₂S₄@TiO₂nanorod arrays as advanced electrode for solid-state asymmetric supercapacitors

Nanotechnology. 2021 Apr 30;32(29). doi: 10.1088/1361-6528/abf693.

Authors

Fangya Qi¹, Han Li², Fan Yang¹, Zhipeng Sun^{1

2}

Affiliations

¹ Materials and Energy School, Guangdong University of Technology, No. 100 Waihuan Xi Road, Guangzhou Higher Education Mega Center, Panyu District, Guangzhou 510006, People's Republic of China.
² Key Laboratory Energy Materials Chemistry, Ministry of Education, Institute of Applied Chemistry, Xinjiang University, Urumqi 830046, Xinjiang, People's Republic of China.

PMID: 33836514
DOI: 10.1088/1361-6528/abf693

Abstract

An integrated electrode of core-shell coaxially structured NiCo₂S₄@TiO₂nanorod arrays/carbon cloth (NiCo₂S₄@TiO₂@CC) have been fabricated, via a two-step hydrothermal method. Comprehensive structural and compositional analyzes are performed to understand the effects of the NiCo₂S₄shell on the TiO₂core. Such core-shell arrays structure can significantly provide abundant electroactive sites for redox reactions, convenient ion transport paths, and favorable structure stability. The NiCo₂S₄@TiO₂@CC electrode represents a splendid specific capacitance (650 F g^-1at 1 A g^-1) and enhanced cycling stability (capacitance retention of 97% over 10 000 cycles at 5 A g^-1). Additionally, the assembled NiCo₂S₄@TiO₂@CC//CNT@CC solid-state asymmetric supercapacitors exhibit a maximal energy density of 0.6 mWh cm^-3at 32.4 W cm^-3, and topping cycling stability (85% capacitance retention after 5000 cycles at 5 mA cm^-2). The results demonstrate that the well-designed NiCo₂S₄@TiO₂@CC presented in this work are applicable for the development of electrode materials in energy storage devices.

Keywords: NiCo2S4; asymmetric supercapacitors; coaxial nanorod arrays; core−shell structure; solid-state.