Electrode and symmetric supercapacitor device performance of boron‐incorporated reduced graphene oxide synthesized by electrochemical exfoliation
R. Naresh Muthu, Sankara Sarma V. Tatiparti
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.