Construction of D-A type porphyrin-phthalocyanine-based polymer hollow tubes for efficient photodegradation and photoelectrochemical sensing of bisphenol A

A series of hollow tubes of porphyrin-phthalocyanine-based conjugated microporous polymer (MPorPc-CMP, M = Co, Ni, Cu, Zn, H-2) within periodic multi-channel donor-acceptor (D-A) structure were successfully synthesized using phthalocyanine monomer with poor solubility as a self-template. The unique hollow tube-like structures provided sufficiently exposed active sites for the adsorption of analytes. A wide range of spectral characterization and DFT calculation found that M in the MPor unit can efficiently tune band structures and built-in electric field between MPor and Pc of the MPorPc-CMPs. Among them, the best-matching band structures and the strongest built-in electronic field between NiPor and Pc units were obtained in NiPorPc-CMP, which promoted carrier separation/transport and suppressed the exciton annihilation. Thus, the NiPorPc-CMP showed the highest bisphenol A (BPA) degradation efficiency and H2O2 generation rate (273 mu mol.g(-1)h(-1)) under visible light illumination. Moreover, the significantly improved cathodic photocurrent of NiPorPc-CMP enabled ultrasensitive and selective BPA detection with a LOD of 0.012 nM within the range of 0.05-5000 nM. This study not only provided a new method for the design and synthesis of morphologically controllable D-A type CMPs but also provided new insights to expand the applications of D-A type CMPs.