Carbonaceous 0D/2D composite photocatalyst for degradation of organic dyes

Photocatalysis technology has stimulated extensive research interest in various fields, but several limitations, such as the inefficient separation ratio of photo-generated charges and the possible release of metal ions from metal oxides or sulfides, need to be overcome before its practical application. Herein, we fabricated a metal-free carbonaceous composite photocatalyst via modification of 2D polymeric carbon nitride (PCN) with 0D graphene quantum dots (GQDs) by an ultrasound-assisted route. Characterization results clearly indicated the formation of 0D/2D composite structure with an intimately contacted interface, and the type II band structure promotes the charge separation between PCN and GQDs. As a result, an enhanced photocatalytic activity for degradation of dyes was achieved by the GQDs/PCN in comparison to the single PCN and GQDs. Furthermore, multiple cycling tests reflected the GQDs/PCN had relatively high photocatalytic durability. This study provides a facile method to construct carbonaceous composite and demonstrates it is a promising photocatalyst for environmental remediation. [Display omitted] •A metal-free 0D/2D GQDs/PCN heterojunction photocatalyst was prepared.•The Type II band structure promoted the charge separation between PCN and GQDs.•The GQDs/PCN showed enhanced photocatalytic activity than the pristine PCN.•The GQDs/PCN had a high stability and photocatalytic durability for dye removal.