Graphitic carbon nitride coupled with perylene nanoparticles as efficient solar photocatalyst

Abstract

Graphitic carbon nitride (CN), a two dimensional (2D) soft nanomaterial is becoming increasingly popular in the field of solar photocatalysis as its surface is modified by incorporating various organic and inorganic guest species. In this study, as a new guest species quasi spherical perylene nanoparticles (PeNPs) were prepared by chemical reduction of perylene-3,4,9,10-tetracarboxylic dianhydride using D-glucosamine hydrochloride, and they were incorporated into CN to form the PeNPs-coupled CN (PeNPs-CN). The prepared PeNPs-CN and CN were characterized in terms of their structural and optical properties, followed by evaluation of their photocatalytic efficiencies by measuring the photodegradation of different dyes like rhodamine B (RhB), eosin yellow (EY) and malachite green (MG) under solar simulator. The PeNPs-CN exhibited higher photocatalytic activity than Degussa P25 (TiO2) and CN under sunlight, indicating that the solar photocatalytic performance of CN was significantly improved by the addition of PeNPs. Analysis of the UV–vis diffuse reflectance and photoluminescence spectra of PeNPs-CN and CN supported that the improved solar photocatalytic efficiency of PeNPs-CN is attributed to both enhancement of visible light absorption and reduction of the charge recombination rates through sensitization by PeNPs. Both superoxide anion radials and hydroxyl radicals formed by the electron holes were observed to play major roles in the solar photocatalytic degradation of pollutant dyes as identified using different radical scavengers.