Precise Manipulation on the Structural Defects of Poly (Triazine Imide) Single Crystals for Efficient Photocatalytic Overall Water Splitting.

Conjugated polymers, represented by polymeric carbon nitrides (PCNs), have risen to prominence as new-generation photocatalysts for overall water splitting (OWS). Despite considerable efforts, achieving highly crystalline PCNs with minimal structural defects remains a great challenge, and it is also difficult to examine the exact impact of complex defect states on OWS process, which largely limits their quantum efficiency. Herein, we devise a 'in-situ salt flux' assisted copolymerization protocol by using nitrogen-rich and nitrogen-deficient monomers to precisely manipulate the structural defects of poly (triazine imide) (PTI) single crystals.

Fully Condensed Poly (Triazine Imide) Crystals: Extended π-Conjugation and Structural Defects for Overall Water Splitting.

Conventional polymerization for the synthesis of carbon nitride usually generates amorphous heptazine-based melon with an abundance of undesired structural defects, which function as charge carrier recombination centers to decrease the photocatalytic efficiency. Herein, a fully condensed poly (triazine imide) crystal with extended π-conjugation and deficient structure defects was obtained by conducting the polycondensation in a mild molten salt of LiCl/NaCl. The melting point of the binary LiCl/NaCl system is around 550 °C, which substantially restrain the depolymerization of triazine units and extend the π-conjugation.

Carbon Vacancies in a Melon Polymeric Matrix Promote Photocatalytic Carbon Dioxide Conversion.

Photosynthetic conversion of CO into fuel and chemicals is a promising but challenging technology. The bottleneck of this reaction lies in the activation of CO , owing to the chemical inertness of linear CO . Herein, we present a defect-engineering methodology to construct CO activation sites by implanting carbon vacancies (CVs) in the melon polymer (MP) matrix.