Ultrasound-promoted synthesis of γ-graphyne for supercapacitor and photoelectrochemical applications

Wen Ding; Mingxuan Sun; Zihan Zhang; Xiaojing Lin; Bowen Gao

doi:10.1016/j.ultsonch.2019.104850

Ultrasound-promoted synthesis of γ-graphyne for supercapacitor and photoelectrochemical applications

Ultrason Sonochem. 2020 Mar:61:104850. doi: 10.1016/j.ultsonch.2019.104850. Epub 2019 Oct 29.

Authors

Wen Ding¹, Mingxuan Sun², Zihan Zhang¹, Xiaojing Lin¹, Bowen Gao¹

Affiliations

¹ School of Materials Engineering, Shanghai University of Engineering Science, Shanghai 201620, China.
² School of Materials Engineering, Shanghai University of Engineering Science, Shanghai 201620, China; Shanghai Collaborative Innovation Center of Laser Advanced Manufacturing Technology, Shanghai 201620, China; State Key Laboratory of Photocatalysis on Energy and Environment, Fuzhou University, Fuzhou 350002, China. Electronic address: mingxuansun@sues.edu.cn.

PMID: 31698197
DOI: 10.1016/j.ultsonch.2019.104850

Abstract

As a novel type of carbon materials, graphynes possesses the merits of high carrier mobility and large surface areas, etc. However, to date, the main research of graphynes is focused on theoretical calculation whereas few strategies have been reported for the fabrication of graphynes. In this work, a facile method named ultrasound-promoted synthesis was developed to fabricate γ-graphyne using PhBr₆ and CaC₂ as the raw materials. The reaction system in argon atmosphere ultrasonically vibrated for 24 h in the ultrasonic bath at a power of 180 W and frequency of 53 kHz. The structure, morphology, and component of the obtained samples were detected by X-ray diffraction, Raman spectroscopy, X-ray photoelectron spectroscopy, FT-IR spectra, scanning electron microscopy, transmission electron microscopy, and the selected area electron diffraction. The electrochemical and photoelectrochemical measurements indicate that γ-graphyne can be used as superior electrode mateirals in supercapacitor and photoelectrochemical catalysis. From the results of galvanostatic charge/discharge measurements, the γ-graphyne supercapacitor delivers a maximum specific capacitance of 81 F/g at 0.2 A/g and a capacitance retention rate of 87.5% after 5000 cycles at 3 A/g. Moreover, UV-vis light photoelectrochemical response and high carrier density are observed for γ-graphyne. It is also demonstrated that the charge-transfer resistance is low by Tafel slopes and Nyquist plots. This work puts forward a new and facile strategy for the fabrication of γ-graphyne and explores its application in the field of solar energy conversion and storage.

Keywords: Carbon; Photoelectrochemical performance; Supercapacitor; Ultrasound irradiation; γ-Graphyne.