N-doped porous carbons derived from Zn-porphyrin-MOF

Abstract

N-doped porous metal-organic framework (MOF)-derived carbons (MDCs) were directly synthesized from a new Zn-DpyDtolP-MOF (ZnDpyDtolP center dot 1/2DMF, H(2)DpyDtolP = 5,15-di(4-pyridyl)-10,20-di(4-methylphenyl)porphyrin) containing a 3D hexagonal network through a self-templated carbonization method. KOH-activated MDC derivatives denoted as MDC-700-nKOH were also prepared with different weight ratios of KOH activator to MDC (MDC : KOH = 1 : n, where n = 1, 2). Compared to bare MDC, MDC-700-nKOH showed effective improvements of both gas sorption and electrochemical capacitive properties. More developed microporosity by KOH activation might induce great enhancement of high operating capacitive performances. The N-doped MDC-700-2KOH had high maximum gravimetric specific capacitance (555.6 F g(-1)) and specific energy (40.4 W h kg(-1)) at 0.1 A g(-1) in 1 M H2SO4. Even at a high current density of 190 A g(-1) in 6 M KOH, it exhibited high capacitive performance with a large specific power of 80 423 W kg(-1). MDC-700-nKOH electrodes also showed good recycling properties of electrochemical capacitance up to 30 000 cycles.