Tuning Catalytic Performance of C₂N/GaN Heterostructure for Hydrogen Evolution Reaction by Doping

Abstract

In this work, a systematic theoretical study of the hydrogen evolution reaction (HER) catalytic activity of C2N/GaN heterostructure is carried out based on first principles. An indirect bandgap of 1.99 eV and type‐II band alignment are formed in the C2N/GaN heterostructure, which can facilitate the spatially efficient separation of photogenerated carrier pairs, and the band edge position matches the reduction potential of water. The catalytic performance of the HER reaction at the C and N sites is compared and that the N site is better in performance is found, but still requires a potential barrier of 0.60 eV. In order to improve the catalytic performance of the C2N/GaN heterostructure, an N atom is replaced by a P atom to obtain P‐C2N/GaN. The band alignment of the P‐C2N/GaN heterostructure is still type‐II, and the band edges satisfy the reduction potential of water. Fortunately, the P or N sites play a crucial role in the HER process with a relatively low overpotential of 0.38 eV, which suggests that P‐C2N/GaN can improve the catalytic performance of the heterojunction. Overall, the P‐C2N/GaN heterostructure has suitable band gap values and band edges, and efficient charge separation in the heterostructure makes it a promising HER catalyst.

The lead-free perovskite-based heterojunction C2N/CsGeI3: an exploration for superior visible-light absorption

“…Moreover, it has been unraveled that the C 2 N exhibits superior visible-light response and chemical activity compared to the other graphene-like carbon nitride derivatives. 23,24 So far, C 2 N-based heterojunctions have been extensively investigated in various fields such as photovoltaics, electrocatalysis and photocatalysis, including C 2 N/GaN, 25 h-BN/C 2 N, 26 C 2 N/MoS 2 , 27 C 2 N/WS 2 , 28 Cs 3 Sb 2 I 9 /C 2 N, 29 C 2 N/antimonene 30 and so forth. It has been confirmed that the incorporation of the C 2 N into these heterojunctions significantly influences the bandgap, particularly affecting the electronic orbits at the bandgap edge.…”

Recent Progress and Perspectives of S-Scheme Heterojunction Photocatalysts for Photocatalytic CO2 Reduction

“…Since 1979, when Inoue reported the ability of semiconductor photocatalysts to reduce CO 2 in water to organic compounds . Researchers have developed a number of semiconductor photocatalysts for photocatalysis, which can be categorized into the six categories below (1) metal oxides, such as TiO 2 , , ZnO; , (2) metal sulfides, such as CdS, ZnS, ZnIn 2 S 4 ; (3) metal nitrides and phosphides, such as GaN, Ni 2 P; (4) layered metal hydroxides, such as NiAl-LDH, MgAl-LDH; (5) metal–organic framework materials (MOFs); and (6) nonmetallic semiconductors, such as g-C 3 N 4 . , …”