Coordinative integration of copper (II) and iron (II) phthalocyanine into amidoximated PAN fiber for enhanced photocatalytic activity under visible light irradiation

Abstract

Metal phthalocyanine (MPc) complexes hold great promise for photocatalysis applications because of their high visible light harvesting efficiency and semiconductive properties. However, the effective development requires the suppression of their rapid charge recombination. Transition metal ions can act as electron traps to enhance the charge separation of semiconductors, but challenges still remain for bimetallic co-catalysis of MPc due to the difficulties in the combination between them. Herein, we proposed a new approach to enable the assisted metal ions to interact with MPc through fibrous support, constructing a novel bimetallic photocatalyst via simultaneously immobilizing iron(II) phthalocyanine (FePc) and Cu(II) onto the surface of amidoximated polyacrylonitrile (PAN) fiber. Taking the photodegradation of organic dyes as model reactions, this bimetallic catalyst achieves much higher photoactivity than that of the monometallic FePc catalyst, and effectively converts surface H2O2 into hydroxyl radicals rather than superoxide radicals and high-valent metal-oxo species. The Cu(II) not only enables the transfer of photoexcited electrons from FePc, but also promotes the running of Fe(II)/Fe(III) cycle to boost reactive radicals generation through H2O2 activation. The strategy of coupling Cu(II) with MPc through fibrous support provides a facile and promising solution for the advancement of MPc-based photocatalysis via visible light energy.