title: Facile Carbonization of Microporous Organic Polymers into Hierarchically Porous Carbons Targeted for Effective CO2 Uptake at Low Pressures.
abstract: The advent of microporous organic polymers (MOPs) has delivered great potential in gas storage and separation (CCS). However, the presence of only micropores in these polymers often imposes diffusion limitations, which has resulted in the low utilization of MOPs in CCS. Herein, facile chemical activation of the single microporous organic polymers (MOPs) resulted in a series of hierarchically porous carbons with hierarchically meso-microporous structures and high CO2 uptake capacities at low pressures. The MOPs precursors (termed as MOP-7-10) with a simple narrow micropore structure obtained in this work possess moderate apparent BET surface areas ranging from 479 to 819 m(2) g(-1). By comparing different activating agents for the carbonization of these MOPs matrials, we found the optimized carbon matrials MOPs-C activated by KOH show unique hierarchically porous structures with a significant expansion of dominant pore size from micropores to mesopores, whereas their microporosity is also significantly improved, which was evidenced by a significant increase in the micropore volume (from 0.27 to 0.68 cm(3) g(-1)). This maybe related to the collapse and the structural rearrangement of the polymer farmeworks resulted from the activation of the activating agent KOH at high temperature. The as-made hierarchically porous carbons MOPs-C show an obvious increase in the BET surface area (from 819 to 1824 m(2) g(-1)). And the unique hierarchically porous structures of MOPs-C significantly contributed to the enhancement of the CO2 capture capacities, which are up to 214 mg g(-1) (at 273 K and 1 bar) and 52 mg g(-1) (at 273 K and 0.15 bar), superior to those of the most known MOPs and porous carbons. The high physicochemical stabilities and appropriate isosteric adsorption heats as well as high CO2/N2 ideal selectivities endow these hierarchically porous carbon materials great potential in gas sorption and separation.
authors.affiliation: College of Chemistry and Chemical Engineering, Central South University , Changsha 410083, China.|State Key Laboratory of Advanced Technology For Materials Synthesis and Processing, Wuhan University of Technology , Wuhan 430070, China.
authors.forename: Shuai
authors.initials: S
authors.lastname: Gu
authors.affiliation: College of Chemistry and Chemical Engineering, Central South University , Changsha 410083, China.
authors.forename: Jianqiao
authors.initials: J
authors.lastname: He
authors.affiliation: College of Chemistry and Chemical Engineering, Central South University , Changsha 410083, China.
authors.forename: Yunlong
authors.initials: Y
authors.lastname: Zhu
authors.affiliation: College of Chemistry and Chemical Engineering, Central South University , Changsha 410083, China.
authors.forename: Zhiqiang
authors.initials: Z
authors.lastname: Wang
authors.affiliation: College of Chemistry and Chemical Engineering, Central South University , Changsha 410083, China.
authors.forename: Dongyang
authors.initials: D
authors.lastname: Chen
authors.affiliation: College of Chemistry and Chemical Engineering, Central South University , Changsha 410083, China.|State Key Laboratory of Advanced Technology For Materials Synthesis and Processing, Wuhan University of Technology , Wuhan 430070, China.
authors.forename: Guipeng
authors.initials: G
authors.lastname: Yu
authors.affiliation: College of Chemistry and Chemical Engineering, Central South University , Changsha 410083, China.
authors.forename: Chunyue
authors.initials: C
authors.lastname: Pan
authors.affiliation: State Key Laboratory of Advanced Technology For Materials Synthesis and Processing, Wuhan University of Technology , Wuhan 430070, China.
authors.forename: Jianguo
authors.initials: J
authors.lastname: Guan
authors.affiliation: Institute of Inorganic Materials, School of Materials Science & Chemical Engineering, Ningbo University , Ningbo, Zhejiang 315211, China.
authors.forename: Kai
authors.initials: K
authors.lastname: Tao
keywords: 9,9′-spirobifluorene; CO2/N2 selectivity; chemical activation; hierarchical pores; microporous polymers; triptycene