Poly(ionic liquid)s as dispersants for facile preparation of hydrophobic porous phthalocyanine complex and application in dye degradation

Abstract

Metal phthalocyanines (MPcs) with unique physical and optical properties can be used as excellent candidates in many application fields. Over the last few decades, these applications have been restricted by a highly spontaneous aggregation of MPc molecules that impedes the accessibility of central active metal sites of MPcs to substrates and impairs catalytic activity of MPcs. Many strategies have been investigated including covalent modification, MPcs immobilization onto solid supports and MPcs encapsulation into porous materials. But, some new problems such as strict operation, inhomogeneous distribution and low capacity MPcs are also the roadblocks in industry applications. In this article, a series of porous imidazolium-based poly(ionic liquid)s cobalt phthalocyanines complexes (PIL-CoPc) were simply and quickly prepared through a template-free ionic complexation method. Linear PILs were used as the dispersants and stabilizers to prevent the aggregation of metal phthalocyanines molecules through coulombic interaction. One of complexes exhibited a spherical meso/macroporous structure. Its SBET was 25.457 m2/g. And the complex has a cobalt phthalocyanines high-load capacity and uniform distribution that is in favor of effective catalytic oxidation to degrade dye RhB in wastewater under mild conditions. The highest degradation efficiency reached to 97.9% under irradiation for 180 min. Within five recycles of reusability, the catalyst showed no significant change on reactivity. This preparation process has characteristics of simpleness, rapidity and low cost for mass production that has a great potential for widely practical application in industry.