Modulating Location of Single Copper Atoms in Polymeric Carbon Nitride for Enhanced Photoredox Catalysis

Abstract

Introducing single-atom metals (SAMs) is a promising strategy to improve photocatalysis of polymeric carbon nitride (PCN), but current studies are limited to loading SAMs on the surface of PCN to serve as active sites. Herein, we report an intercalation-structured hollow carbon nitride sphere composed of carbon nitride nanosheets (HCNS) with atomically dispersed Cu1N3 moieties embedded within nanosheets (Cu1@HCNS) prepared by a facile molecular assembly approach. It exhibits far superior photoredox catalysis to the pristine HCNS and the modified HCNS with Cu1N3 moieties anchored on the surface of nanosheets (Cu1/HCNS) for solar hydrogen production (3261 μmol g–1 h–1 rate with 7.1% of apparent quantum yield), in which the embedded single-atom Cu acts as a modifier to effectively modulate the electron structure and remarkably promote interfacial charge transfer of PCN rather than act as active sites to facilitate surface reaction. It can be extended to the nonoxygen coupling of benzylamine and derivants to corresponding imines, and the unexpectedly high reaction rate is achieved. The promoting effect strongly depends on the location of single-atom Cu in the PCN, and the coordination method is a very effective strategy to introduce single-atom metals in terms of the improvement in photocatalysis of PCN owing to the intensified metal–PCN interaction. This work opens up a window for further improving the photocatalytic efficiency of carbon nitride in terms of solar fuel production and clean organic synthesis.

Hydroxyl-group-modified polymeric carbon nitride with the highly selective hydrogenation of nitrobenzene to N-phenylhydroxylamine under visible light

“…15,16 Then, designing a specific catalyst that could abstract hydrogen from the hydrogen donor efficiently and drive the reaction under neutral environment was essential. As a metal-free, environmentally friendly visible light absorbable photocatalyst, polymeric carbon nitride (PCN) has raised wide concern in photodegradation of pollutants, [17][18][19] reduction of CO 2 , 20,21 H 2 production [22][23][24] and, in particular, organic photosynthesis. [25][26][27][28][29][30][31][32][33] Many works had been reported that the surface modified methods can regulate the catalytic performance of the polymeric carbon nitride, and even control the selectivity of the reaction.…”

Efficient Electronic Modulation of g-C 3 N 4 Photocatalyst by Implanting Atomically Dispersed Ag 1 -N 3 for Extremely High Hydrogen Evolution Rates

“…melamine-Ag complex (Mel-Ag) with cyanuric acid followed by a pyrolysis process in N 2 (Figure 1a). According to our previous reports, 39,42 1h,i, highlighted by yellow circles). Supporting Information Figure S4 and Supporting Information Table S1 implies no obvious influence on the textural properties and N/C ratio after the introduction of a low amount of Ag or Cu atoms within the framework.…”

“…39,[42][43][44] A new peak deconvoluted on N 1s XPS spectra of Ag 1 N -HCNS and Cu N 3 -HCNS (Figures 2ac) can be assigned to Ag−N bonding and Cu−N bonding, respectively. 39,40 The lowering content of pyridinic N (Supporting Information Table S2) is a further indicator of coordination of Ag or Cu with pyridinic N. 39 Furthermore, the remarkably increased intensity of Ag 3d and Cu 2p XPS peaks after Ar plasma etching (Supporting Information Figure S6) indicates the implantation of Ag and Cu atoms within the carbon nitride nanosheets of Ag 1 N 3 -HCNS and Cu 1 N 3 -HCNS, respectively. 39 The electronic structure and local coordination environment of Ag and Cu species are further investigated by X-ray absorption spectroscopy (XAS).…”

Single Metal Atom Decorated Carbon Nitride for Efficient Photocatalysis: Synthesis, Structure, and Applications

“…Zhao and co‐workers reported hollow carbon nitride spheres with an intercalation structure, which is composed of atom‐dispersed carbon nitride nanosheets. [ 94 ] These nanosheets were prepared by a simple molecular assembly method and each Cu atom coordinates with three N atoms, giving a configuration of Cu 1 –N 3 . The resultant material performed much better in photocatalytic H 2 production than unmodified carbon nitride nanosheets (HCNS) and HCNS modified by Cu 1 –N 3 groups on the surface of the nanosheets.…”