Crystallization of Covalent Triazine Frameworks via a Heterogeneous Nucleation Approach for Efficient Photocatalytic Applications

Crystalline
covalent triazine frameworks (CTFs) have shown intriguing
applications in photoelectric fields. So far, a number of synthetic
strategies based on homogeneous nucleation have been reported. However,
it still remains a great challenge to acquire crystalline CTFs with
wide structural diversity. Here, we report the synthesis of crystalline
CTFs via a novel heterogeneous nucleation strategy, which exhibits
a wide monomer scope. The crystalline CTFs could be successfully induced
and grown on the lattice planes of salt, which works as a heterogeneous
nucleation agent. The CTFs of different structures were successfully
obtained with high degrees of crystallinity and nanosheet morphologies.
These crystalline CTFs with structural diversity showed excellent
activities in photocatalytic hydrogen evolution from sea water. The
highest hydrogen evolution rate from “sea water” reached
791 μmol h–1 with a quantum yield of 12.8%
under 420 nm irradiation. This work successfully demonstrated a new
approach to synthesize crystalline CTFs with a wide monomer scope
for photoelectric applications.