Preparation and supercapacitive properties of B, N co-doped porous carbons

Herein, we employed (CH3COO)(2)Zn as template to prepare B, N co-doped porous carbons (BN-PC) by using phenanthroline as precursor and N source, K2B4O7 as B source. The effect of template mass on the structure and electric storage properties of BN-PC5 was investigated. When the mass of (CH3COO)(2)Zn was 5 g, the B and N heteroatom content of BN-PC5 was 20.21% and 18.29%, respectively. As the electrode materials for supercapacitors, BN-PC5 exhibited a high specific capacitance of 255 F.g(-1) at 0.05 A.g(-1), an excellent rate performance of 188 A.g(-1) at 20 A.g(-1) and outstanding cycle stability with 97% of initial capacitance retention after 10 000 cycles in 6 mol.L-1 KOH aqueous electrolyte. The energy density of BN-PC5 capacitor reached 27 Wh.kg(-1) at an average power density of 56 W.kg(-1) in 3 mol.L-1 ZnSO4 aqueous electrolyte.