2D/2D Nb₃O₇F/g-C₃N₄ Heterojunction Photocatalysts with Enhanced Hydrogen Evolution Activity

Abstract

Constructing two-dimensional (2D)/2D heterojunctions with intimate interfacial contact is of great importance to achieve high photocatalytic efficiency for hydrogen evolution. Herein, 2D/2D niobium oxyfluoride (Nb 3 O 7 F)/graphitic carbon nitride (g-C 3 N 4 ) heterojunction photocatalysts were prepared by a two-step hydrothermal/calcination method. As expected, the obtained 2D/2D Nb 3 O 7 F/g-C 3 N 4 heterojunctions exhibited a high photocatalytic hydrogen evolution rate of 1242.0 μmol h −1 g −1 , which was approximately 3 times higher than that of pure g-C 3 N 4 (427.2 μmol h −1 g −1 ). Furthermore, cycling experiments verified that the heterojunctions have good stability after four cycles. The remarkable photocatalytic activity was predominantly attributed to the enhanced specific surface area, the improved photogenerated electron/hole separation efficiency, and the inhibited carrier recombination. This work may give a deep insight into heterojunction photocatalysts for application of hydrogen production.

Improving Charge Carrier Separation through S-Scheme-Based 2D–2D WS2/Sulfur-Doped g-C3N4 Heterojunctions for a Superior Photocatalytic O2 Reduction Reaction

“…Recently, Wang et al reported a 2D/2D g-C 3 N 4 /In 2 S 3 photocatalyst for photocatalytic H 2 O 2 production . Similarly, Li and his group members designed a 2D/2D Nb 3 O 7 F/g-C 3 N 4 heterojunction for photocatalytic H 2 evolution . However, a few numbers of tungsten disulfide-modified g-C 3 N 4 heterostructures have been reported; however, to our information, nonmetal-doped g-C 3 N 4 -based S-scheme heterojunctions with 2D WS 2 have not been investigated yet.…”

“…32 Similarly, Li and his group members designed a 2D/2D Nb 3 O 7 F/g-C 3 N 4 heterojunction for photocatalytic H 2 evolution. 33 However, a few numbers of tungsten disulfide-modified g-C 3 N 4 heterostructures have been reported; however, to our information, nonmetal-doped g-C 3 N 4 -based S-scheme heterojunctions with 2D WS 2 have not been investigated yet. Encouraged by the above discussion, we have synthesized a 2D−2D WS 2 decorated SCN heterojunction composite by using wet impregnation and calcination techniques, as illustrated in Scheme 1.…”

Preparation of novel Au-Nb3O7F nanosheets for the photodegradation of tetracycline hydrochloride

“…2.9–3.2 eV, as well as low cost and high chemical stability. Nb 3 O 7 F is a commonly used material for a variety of applications including catalysts, sensors, recording materials, electrochemical supercapacitors, Li-ion batteries, and field emission materials ( Idrees et al, 2014 ; Hirai et al, 2018 ; Chen et al, 2021 ; Li et al, 2021 ; Zhang et al, 2021 ). However, Au combined with Nb 3 O 7 F had been never investigated before, including photocatalytic degradation of contaminants in water.…”

Effective Low-Powered Photocatalytic Disinfection via Synchronous Introduction of Oxygen Dopants and Carbon Defects in Carbon Nitride

“…Prior studies in the field of photocatalytic disinfection focused on constructing a heterojunction composite to address these concerns. 8 The energy band offset occurring at the interface between the components within a composite material generates an internal electric field that governs the direction of transfer and results in the spatial separation of electrons and holes. Often, an increase in surface area with the incorporation of other materials confers the composite with an extended light harvesting capability.…”

“…Graphitic carbon nitride (g-C 3 N 4 ) holds great potential as a green photocatalyst owing to its metal-free nature, visible-light activity, facile and scalable synthesis, high chemical and thermal stability, and ease of functionalization due to its polymeric chain tunability and two-dimensional (2D) characteristic. , Its photocatalytic performance, however, is suppressed by high charge recombination, insufficient absorption of visible light, and low surface area. Prior studies in the field of photocatalytic disinfection focused on constructing a heterojunction composite to address these concerns . The energy band offset occurring at the interface between the components within a composite material generates an internal electric field that governs the direction of transfer and results in the spatial separation of electrons and holes.…”