Layer-Structured Copper Antimony Chalcogenides (CuSbSe_xS_2–x): Stable Electrode Materials for Supercapacitors

Abstract

The ever-growing need for energy generation and storage applications demands development of materials with high performance and long term stability. A sizeable number of chalcogenide-based materials have been investigated for supercapacitor applications. Layerstructured chalcogenides are advantageous in terms of providing large surface area with good ionic conductivity and ability to host a variety of atoms or ions between the layers. CuSbS 2 is a ternary layered chalcogenide material that is composed of earth abundant and less-toxic elements. For the first time we have developed a simple colloidal method for the synthesis of CuSbSe x S 2-x mesocrystals over the whole composition range (0 ≤ x ≤ 2) by substitution of S with Se. Our approach yields mesocrystals with belt-like morphology for all the compositions. X-ray diffraction results show that substitution of sulfur with selenium in CuSbS 2 enables tuning the width of the interlayer gap between the layers. In order to investigate the suitability of CuSbSe x S 2-x mesocrystals for supercapacitor applications, we have carried out electrochemical measurements by cyclic voltammetry and galvanostatic charge-discharge measurements in 3M KOH, NaOH and LiOH electrolytes. Our investigations reveal that the mesocrystals exhibit promising specific capacitance values with excellent cyclic stability. The unique properties of CuSbSe x S 2-x mesocrystals make them attractive both for solar energy conversion and energy storage applications.

Layered ternary sulfide CuSbS2 nanoplates for flexible solid-state supercapacitors

“…These values are higher than those for CuSbE 2 (E = S or Se) mesocrystals and comparable to the specific capacitance values reported for other chalcogenide nanocrystals (SnSe, CoS, CuS) 49,30,50,38. The C sp values for 55 ± 6.5 nm thick nanoplates with KOH as electrolyte are determined to be 100, 96, 94, 92, 89, 92, 99 F/g at applied currents of 0., respectively.…”

“…32,33 The crystal structure comprises of SbS 2 and CuS 3 interconnected chains that layer perpendicular to the c-axis. 38 Herein, we report results of a systematic study of CuSbS 2 nanoplates with varied thicknesses for use in supercapacitors. 32,33 Because of its direct band gap at solar wavelengths and high absorption coefficient (>10 4 cm -1 ), CuSbS 2 has been studied for solar cell applications.…”

Role of interlayer coupling for the power factor ofCuSbS2andCuSbSe2

“…1). The optimized [37] distance between the Sb atoms of neighboring atomic layers is 2.00 and 2.08Å for CuSbS 2 and CuSbSe 2 , respectively, in reasonable agreement with the experimental values (2.05 and 2.14Å [35]). The band structures and densities of states in the top row of Fig.…”

CuSbSe2 as a Potential Photovoltaic Absorber Material: Studies from Theory to Experiment

“…(iii) CuSbSe 2 crystallizes in an orthorhombic layered structure with Pnma space group. [ 11,12 ] It is composed of double CuSbSe 2 layers with an interlayer distance of 7.59 Å held together by weak van der Waals forces, as shown in Figure 1 . Each layer can wileyonlinelibrary.com be viewed as consisting of SbSe 2 and CuSe 3 chains along the b -axis connected by Sb square pyramids and CuSe 4 tetrahedral links.…”