Enhanced Schottky effect of a 2D–2D CoP/g-C₃N₄ interface for boosting photocatalytic H₂ evolution

Abstract

As emerging noble metal-free co-catalysts, transition metal phosphides have been employed to improve photocatalytic H2 production activity. Herein, the metallicity of CoP, as a representative phosphide, and the Schottky effect between CoP and g-C3N4 are confirmed via theoretical calculations. Then, a 2D/2D structure is designed to enlarge the Schottky effect between the interfaces, for which the apparent quantum efficiency of the photocatalytic H2 evolution is 2.1 times that of corresponding 0D/2D heterojunctions. The morphology, microstructure, chemical composition, and physical nature of pristine CoP, g-C3N4, and the composites are characterized in order to investigate the dynamic behavior of photo-induced charge carriers between CoP and g-C3N4. Based on the measurements, it is proposed that the efficient electron collecting effect of CoP can be attributed to the superior interfacial contact and Schottky junction between the CoP and g-C3N4 interfaces. Furthermore, the excellent electrical conductivity and low overpotential of CoP make water reduction easier. This work demonstrates that the construction of a 2D/2D structure based on a suitable Fermi level is crucial for enhancing the Schottky effect of transition metal phosphides.

Electrostatic self‐assembly of 2D‐2D CoP/ZnIn2S4 nanosheets for efficient photocatalytic hydrogen evolution

“…In Figure 4B-D, the binding Figure 4E,F). 34 All the shift of the peaks indicates the existence of strong electronic interaction and formation of chemical bonding between ZnIn 2 S 4 and CoP, which promotes the interface charge transfer. 23,35 Generally, the increase in binding energy suggests the weakened electron screening effect resulted from the decreased electron cloud density, whereas the decrease in binding energy indicates the promoted electron screening effect caused by the increase in electron cloud density.…”

Cu3P and Ni2P co‐modified g‐C3N4 nanosheet with excellent photocatalytic H2 evolution activities

“…The (100) lattice plane corresponds to the structure of graphitic carbon nitride, whereas the (002) crystal face is ascribed to interlayer superposition reflection of melon networks. [53][54][55] The typical diffraction peaks at 36.0°, 39.1°, 41.6°, 45.1°and 46.2°, correspond to the (112), (202), (211), (300) and (113) planes of Cu 3 P (JCPDS card no. 71-2216), 56 whereas the peaks at 40.8°, 44.6°, 47.3°, 54.2°and 54.9°are in close accordance with the (111), (201), (210), (300) and (211) planes of Ni 2 P (JCPDS card No.…”

One‐Step Solid‐Phase Synthesis of 2D Ultrathin CdS Nanosheets for Enhanced Visible‐Light Photocatalytic Hydrogen Evolution

“…Since the report of the photoelectrocatalytic splitting of water on TiO 2 electrodes in 1972, various photocatalytic materials have been widely studied and extensively developed for the potential application of photocatalytic hydrogen evolution . Photocatalysts with 2D ultrathin nanosheet structures are gradually attracting increased attention and interest from researchers because of their special characteristics, such as unique in‐plane anisotropic structure, large surface areas, high electrical conductivity, and abundant exposed sites . However, these 2D photocatalysts are mostly newly developed materials, such as graphene, C 3 N 4 , and MXene or single‐element photocatalysts, such as phosphorene and silicene .…”