Self-Reducible Conjugated Microporous Polyaniline for Long-Term Selective Cr(VI) Detoxication Driven by Tunable Pore Dimension

A simple methodology to controllably tune the pore size and Cr(VI) adsorption capacity was reported herein to synthesize a new series of conjugated microporous polyaniline (CMPA) networks. The well-ordered micropore was acquired through our very recent Bristol-Xi'an Jiaotong method, and the pore size was fine-tuned to increase with the increasing length of linkers, mimicking covalent organic frameworks and metal organic frameworks very much. A selective ultrahigh adsorption capacity of 520.8 mg/g was achieved by CMPA-1 in a very fast manner, with a systematically gradual decrease to 173.9 mg/g of CMPA-3 by enlarging the pore size of the networks, featuring tunable adsorption capacity through molecular-size-recognition mechanism. Additionally, our robust CMPA networks, which were constructed by Buchwald-Hartwig chemistry, showed the complete function of polyaniline and were capable of providing, besides large storage capacity for Cr(III), at least 10 reductant/desorption-free cycles for effective Cr(VI) reduction and detoxication through their novel self-reducible redox states. Outcomes showed that our CMPAs could be applied as new self-healing scavengers in the next generation for Cr(VI) storage and detoxication.