Non-Kekulé copolymer films for optoelectronics

We investigate the synthesis and properties of a photoactive copolymer film, gCN- co -gC, which integrates graphitic carbon (gC) domains into a graphitic carbon nitride (gCN) network. The film, produced via vapor-deposition copolymerization of melamine and glucose, addresses two significant challenges of gCN: limited optical absorption range and poor processability. As the amount of gC increases, the gCN- co -gC film shows enhanced optical absorption, extending into the visible light spectrum (>400 nm), and improved electrical conductivity, making it suitable for optoelectronic applications. The study also reveals that gCN- co -gC posesses stable radicals even in the dark at room temperature. This suggests that the open-shell non-Kekulé structures disrupt electron–hole recombination, realizing metal-free paramagnetic copolymers.