Partially cross-linked carbon nitride with unimpeded charge transfer between different chains for boosting photocatalytic hydrogen production

Abstract

A heptazine based, partially cross-linked carbon nitride (PC-CN) was successfully prepared via a solid-chloride-salts-assisted polycondensation method. The cross-linking favors the charge transport between different chains, thus dramatically boosting the photocatalytic...

Supermolecule Polymer Derived Porous Carbon Nitride Microspheres with Controllable Energy Band Structure for Photocatalytic Hydrogen Evolution Reaction

“…Finally, CN with altered energy band structure will be acquired after simple heat treatments at 550 °C with a heating rate of 5 °C min −1 in muffle furnace for different hours. These photocatalysts were marked as CN-4, CN-8, CN-12, CN-14, CN-16, CN-20, and CN-24 corresponding to the material synthesized with various heating time (4,8,12,14,16,20, and 24 h). Bulk-CN got by direct calcination of urea prepared for comparison.…”

“…[5][6][7] Graphitic carbon nitride (g-CN) is an organic non-metallic n-type semiconductor with visible light response, which possesses the advantages of stable chemical properties, simple preparation, easy functionalization, environmental friendliness, and low raw material cost. [8][9][10][11] Moreover, the photogenerated electrons of graphitic CN endow with strong reduction ability originating from its relatively negative conduction band position. Howbeit, the unfavorable utilization rate of visible light, easy recombination of photogenerated charges, and adverse electronic conductivity limit the further improvement of its photocatalytic performance.…”

Cyano‐Rich g‐C3N4 in Photochemistry: Design, Applications, and Prospects

“…At present, the molten salt method has become one of the overriding means to synthesize cyano‐rich g‐C 3 N 4 . Currently, the main method used is to mix two or more alkali metal salts (KCl/LiCl (most), KCl/LiBr, NaCl/LiCl, LiI/KI, LiBr/KBr, KCl/KSCN, KCl/KOCN, LiCl/KSCN, KI/LiI, KCl/NaCl/LiCl) with the precursors (melamine, urea, dicyandiamide, CH 5 N 3 ·HCl, guanidine hydrochloride, NH 4 SCN, carbohydrazide) or synthetic intermediate or original carbon nitride uniformly, [ 33,40,49,56–81 ] and then heat them in a tube furnace (Air, Ar or N 2 ) or muffle furnace to a certain temperature (450–650 °C) to react for a period of time, and then wash off the salts with hot water, and finally obtain the sample by drying. In this process, alkali metal salts can play the role of a class of template agent, speed up the reaction rate, make the sample more homogeneous, improve the crystallinity of the sample, etc.…”

Effective inter-chain charge transfer and high charge mobility in polymeric carbon nitride arising from controllable molecular structures for enhanced photocatalytic H2O2 and H2 production

“…18,19 However, in ionic KCl/LiCl, it seems that the linking reaction is too fast for the heptazine units to form. 20 Consequently, a triazine-based 2D carbon nitride named polytriazine imide (PTI) is produced. As the small conjugated building blocks are unfavorable for light harvesting and fast charge mobility, PTI still generally exhibits moderate photocatalytic activity.…”