Interfacial self-assembly of carbon nitride-based nanocomposites with zinc terpyridyl coordination polymers for photocurrent generation and the photocatalytic degradation of organic dyes

Abstract

Graphite-like carbon nitride (g-C3N4)-based nanocomposites with zinc terpyridyl (ZnTPy) coordination polymers (CPs) were developed for photo-induced current generation and the catalytic degradation of organic dyes. The oxidized g-C3N4 nanoparticles (O-g-C3N4) were reacted with silane and terpyridyl benzyl bromide (TPyBenBr) to form O-g-C3N4TPy nanohybrids, which then acted as a support for the construction of O-g-C3N4-based nanocomposites, using Zn(CF3SO3)2 as a connector, and bidentate ligand of 1,4-di([2,2′:6′,2′'- terpyridin]-4′-yl)benzene (BTPy) as a linker, respectively. The luminescent emission features revealed that the recombination of charged carriers was inhibited in the O-g-C3N4@(ZnBTPy)n nanocomposites. As a consequence, the photocurrent density for the electrode, modified by the developed nanocomposites, was about 5.6 times higher than that modified by the original O-g-C3N4 particles; furthermore, their catalytic degradation efficiency for methyl orange (MO) and Congo red (CR) was about 20–25 times higher than that for the original O-g-C3N4 nanoparticles. The improved performance was attributed to the fact that, in addition to their enhanced absorption ability, the ZnBTPy CP films could effectively improve the electron transfer efficiency and generation of O2− radicals on the surfaces of the nanocomposites.