In-situ self-templating synthesis of 3D hierarchical porous carbonsfrom oxygen-bridged porous organic polymers for highperformance supercapacitors

It is a big challenge to well control the porous structure of carbon materials for supercapacitor application.Herein,a simple in-situ self-templating strategy is developed to prepare three-dimensional(3D)hierarchical porous carbons with good combination of micro and meso-porous architecture derived from a new oxygen-bridged porous organic polymer(OPOP).The OPOP is produced by the condensation polymerization of cyanuric chloride and hydroquinone in NaOH ethanol solution and NaCl is in-situ formed as by-product that will serve as template to construct an interconnected 3D hierarchical porous architecture upon carbonization.The large interface pore architecture,and rich doping of N and O heteroatoms effectively promote the electrolyte accessibility and electronic conductivity,and provide abundant active sites for energy storage.Consequently,the supercapacitors based on the optimized OPOP-800 sample display an energy density of 8.44 and 27.28 Wh·kg^(−1)in 6.0 M KOH and 1.0 M Na2SO4 electrolytes,respectively.The capacitance retention is more than 94%after 10,000 cycles.Furthermore,density functional theory(DFT)calculations have been employed to unveil the charge storage mechanism in the OPOP-800.The results presented in this job are inspiring in finely tuning the porous structure to optimize the supercapacitive performance of carbon materials.