C₃N₂: the missing part of highly stable porous graphitic carbon nitride semiconductors

Abstract

Two-dimensional (2D) porous graphitic carbon nitrides (PGCNs) with semiconducting features have attracted wide attention because of built-in pores with various active sites, large surface area, and high physicochemical stability. However,...

Prediction of two-dimensional C3N2 semiconductors with outstanding stability, moderate band gaps, and high carrier mobility

“…2(b) further confirm that both C 3 N 2 monolayers exhibit notable energy stability advantages over synthesized 2D carbon nitride materials such as C 3 N 5 (−5.81 eV per atom), 14 C 3 N 4 (−6.05 eV per atom), 8 C 6 N 6 (−6.24 eV per atom), 16 and C 4 N 3 (−6.26 eV per atom). 15 Notably, P-C 3 N 2 exhibits comparable formation and cohesive energies to the recently theoretically proposed T-C 3 N 2 monolayer, 41 and it is more energetically stable. These findings indicate that both P-C 3 N 2 and I-C 3 N 2 possess excellent energy stability and are promising candidates for experimental synthesis.…”

“…S1. † Among these, T-C 3 N 2 41 and pc-C 3 N 2 42 have been previously reported in theoretical studies. Further formation energy calculations revealed that P-C 3 N 2 , T-C 3 N 2 , and I-C 3 N 2 have energies ≤0.30 eV per atom.…”

From Porphyrin-Like Rings to High-Density Single-Atom Catalytic Sites: Unveiling the Superiority of p-C2N for Bifunctional Oxygen Electrocatalysis

“…The uniaxial stress–strain curves reveal that the tensile strength in the x and y directions is 81.8 and 192.5 N m –1 , respectively, with corresponding fracture strains of 16 and 22%. This is better than that of C 2 N-h2D (with uniaxial tensile strain limits of 13 and 17% along the x and y directions) and larger than those of C 3 N 5 (12%), T-C 3 N 2 (14%), and g-C 3 N 4 (11%) . The reason for the larger axial fracture strain is that some carbon–carbon double bonds directly bear the tensile load.…”

“…The computed values for Young’s modulus [ Y (θ)] of single-layer p-C 2 N, as shown in Figure a, exhibit significant anisotropy. The maximum value of Y (θ) of p-C 2 N is 85.79 N/m, similar to that of Cu 2 Si (93 N m –1 ), larger than that of C 3 N 5 (38 N m –1 ) and silicene (71 N m –1 ), and lower than that of C 2 N-h2D (159 N m –1 ), T-C 3 N 2 (177 N m –1 ), and graphene (340 N m –1 ), indicating that the p-C 2 N monolayer has favorable in-plane flexibility. Poisson’s ratio [ v (θ)] of the p-C 2 N monolayer, as shown in Figure b, is from 0.16 to 0.33, with an average of 0.26.…”

“…The experimental synthesis is larger than that of silicene (3.71 eV/atom) 53 and slightly smaller than that of C 3 N (7.08 eV/ atom) and graphene (7.95 eV/atom). 54 larger than that of C 3 N 5 (38 N m −1 ) 55 and silicene (71 N m −1 ), 56 and lower than that of C 2 N-h2D (159 N m −1 ), 57 T-C 3 N 2 (177 N m −1 ), 58 and graphene (340 N m −1 ), 56 indicating that the p-C 2 N monolayer has favorable in-plane flexibility. Poisson's ratio [v(θ)] of the p-C 2 N monolayer, as shown in Figure 2b, is from 0.16 to 0.33, with an average of 0.26.…”