In-situ grafting of Au and Cu nanoparticles over graphitic carbon nitride sheets and unveiling its superior supercapacitive performance as a hybrid composite electrode material. (1st December 2021)

• Record Type: Journal Article
• Authors: Yesmin, Sebina; Devi, Meghali; Hussain, Inamul; Dasgupta, Rajdeep; Dhar, Siddhartha S.
• Is Part Of: Journal of energy storage. Volume 44(2021)Part A
• Publication Date: 2021-12-01
• Subjects: Bimetallic nanocomposites -- Graphitic carbon nitride -- Supercapacitors electrode -- Synergistic effect -- High specific energy/specific power; Energy storage -- Periodicals; Energy storage -- Research -- Periodicals; 621.3126
• DOI: 10.1016/j.est.2021.103308
• Languages: English
• ISSNs: 2352-152X

Abstract

Highlights: Bimetallic hybrid composite Au-Cu graphitic carbon nitride material is proposed for supercapacitative application. Au and Cu nanoparticles were grafted over graphitic carbon nitride sheets with one pot reduction method. Au-Cu/g-C3 N4 hybrid exhibits a high specific capacitance of 506.25 F/g at current density of 1.25 A/g and a specific energy of 59.3 Wh/kg at a specific power of 2.49 kW/kg. It shows good cycle stability with 76.1% capacitance retention after 5000 cycles at 5 A/g current density. Abstract: In this article, a bimetallic hybrid composite of Au and Cu nanoparticles over graphitic carbon nitride has been reported as supercapacitor electrode material. The bimetallic Au-Cu/g-C3 N4 hybrid was synthesized using facile one-phase impregnation of Au and Cu nanoparticles in holey g-C3 N4 sheets. The as-synthesized materials were systematically characterized to assess structural, morphological, electronic, and thermal properties. The electrochemical tests revealed that the Au-Cu/g-C3 N4 hybrid uncovers a superior specific capacitance of 506.25 F/g at 1.25 A/g current density amiable cycle stability with 76.1% capacitance retention at 5 A/g current density after 5000 cycles and excellent rate capability. Our designed asymmetric supercapacitor device based on Au-Cu/g-C3 N4 hybrid unveils specific energy of 59.3 Wh/kg at a specific power of 2.49 kW/kg. The substantial enhancement in supercapacitor performance of Au-Cu/g-C3 N4 compared to pristine g-C3 N4, Au/g-C3 N4, and Cu/g-C3 N4 is attributed to synergy between Au, Cu nanoparticles, and semiconductor g-C3 N4 surface. In hybrid electrode material, the mass ratio of components plays a vital role synergistic supercapacitive effect. Graphical abstract: The bimetallic Au-Cu/g-C3 N4 with superior specific capacitance of 506.25 F/g at 1.25 A/g current density and rate capability even at the high current density and good cycle stability with 76.1% capacitance retention after 5000 cycles at 5 A/g current density. Image, graphical abstract