Electrode and symmetric supercapacitor device performance of boron‐incorporated reduced graphene oxide synthesized by electrochemical exfoliation

Abstract

Abstract Boron‐incorporated reduced graphene oxide (B‐rGO) is synthesized via novel single‐step potentiostatic exfoliation at 3 V vs Ag/AgCl employing (NH 4 ) 2 SO 4 + B(OH) 3 electrolyte for supercapacitor applications. Structural characterization is performed by XRD, Raman, XPS, VB, SEM, TEM, and BET analysis. Eventually, B‐rGO synthesis scheme is proposed. The electron‐deficient B causes p‐doping in B‐rGO forming BCO 2 , BC 2 O, and BC 3 (XPS), redshift of 2D band (Raman) and blue shifts in C 2p‐ π peaks and E f in VB. B‐rGO exhibits specific capacitances ( C sp ) of 446 F g −1 at 0.1 A g −1 and 284 F g −1 at 20 A g −1 in 6 M KOH. Upon 2000 charge/discharge cycles at 5 A g −1 , 95.6% capacitance is retained. B‐rGO gives energy and power densities of 25.2 W h kg −1 and 8064 W kg −1 at 20 A g −1 . The remarkably high energy density of B‐rGO is attributed to p‐doping effect. B‐rGO exhibits superior performance, compared with rGO synthesized from (NH 4 ) 2 SO 4 . A symmetric B‐rGO supercapacitor device is fabricated and exhibits C sp of 120 F g −1 at 0.1 A g −1 . At 20 A g −1 the energy and power densities are 6.45 W h kg −1 and 8000 W kg −1 , respectively. The device retains 89.8% capacitance upon 2000 charge/discharge cycles.