Graphite Nitride Carbon (g-C₃N₄) and Borates as Near-UV Heterogeneous Photoinitiators for Acrylate Photopolymerization

Abstract

Organic small-molecule photoinitiators (PIs) suffer from inherent problems such as residue after curing, toxicity, and yellowing; herein, we report a heterogeneous PI consisting of graphite carbon nitride (g-C 3 N 4 ) and tetra-n-butylammonium n-butyltriphenylborate (PhB) (g-C 3 N 4 /PhB), which provide excellent photopolymerization ability under a light-emitting diode at 365 nm (LED@365 nm) as the light source. g-C 3 N 4 acts as a photosensitizer generating the electron− hole pairs during irradiation and undergoing electron transfer with PhB, resulting in PhB releasing n-butyl radicals for initiating polymerization. Moreover, g-C 3 N 4 in the g-C 3 N 4 /PhB photoinitiation system is easy to separate for recycling, showing exceptional photocatalytic stability even after 8 cycles.