Microwave synthesis of histidine-functionalized graphene quantum dots/Ni-Co LDH with flower ball structure for supercapacitor

Hengrui Qiu; Xuejiao Sun; Shengli An; Dawei Lan; Jinlong Cui; Yongqiang Zhang; Wenxiu He

doi:10.1016/j.jcis.2020.02.018

Microwave synthesis of histidine-functionalized graphene quantum dots/Ni-Co LDH with flower ball structure for supercapacitor

J Colloid Interface Sci. 2020 May 1:567:264-273. doi: 10.1016/j.jcis.2020.02.018. Epub 2020 Feb 6.

Authors

Hengrui Qiu¹, Xuejiao Sun¹, Shengli An¹, Dawei Lan¹, Jinlong Cui¹, Yongqiang Zhang², Wenxiu He³

Affiliations

¹ School of Chemistry and Chemical Engineering, Inner Mongolia University of Science & Technology, Baotou, Inner Mongolia 014010, China.
² School of Chemistry and Chemical Engineering, Inner Mongolia University of Science & Technology, Baotou, Inner Mongolia 014010, China. Electronic address: yongqiang_zhang1203@foxmail.com.
³ School of Chemistry and Chemical Engineering, Inner Mongolia University of Science & Technology, Baotou, Inner Mongolia 014010, China. Electronic address: wenxiu_he@foxmail.com.

PMID: 32062489
DOI: 10.1016/j.jcis.2020.02.018

Abstract

A flower ball-like histidine-functionalized graphene quantum dots/Ni-Co LDH (His-GQD/LDH) composite is synthesized via microwave method. The GQDs are uniformly interspersed on LDH surface and the radius of flower balls is approximately 200 nm. The synergistic effect of His-GQD and LDH can signally increase the specific surface areas and conductivity of the composite, thus endowing the composite high specific capacitance (1526 F g^-1) and an admirable cycling stability (82.36% capacitance retention). Moreover, we have manufactured a supercapacitor employing His-GQD/LDH and active carbon (AC) as positive/negative electrodes. The device exhibits the maximum energy of 48.89 W h kg^-1 at 0.80 kW kg^-1, as well as prominent cycling stability (91.13% capacitance retention). This work provides a practicle experimental method of synthesizing hybridizing histidine-functionalized carbon derivatives with LDH by microwave synthesis. Meanwhile, we are optimistic to believe that the electrode material can be extensively applied for supercapacitor because of its splendid electrochemical properties and facile synthesis.

Keywords: Flower ball; His-GQD/LDH; Microwave method; Supercapacitors.