Interfacial engineering of graphitic carbon nitride (g-C3N4)-based metal sulfide heterojunction photocatalysts for energy conversion: A review

Abstract

As one of the most appealing and attractive technologies, photocatalysis is widely used as a promising method to circumvent the environmental and energy problems. Due to its chemical stability and unique physicochemical, graphitic carbon nitride (g-C3N4) has become research hotspots in the community. However, g-C3N4 photocatalyst still suffers from many problems, resulting in unsatisfactory photocatalytic activity such as low specific surface area, high charge recombination and insufficient visible light utilization. Since 2009, g-C3N4-based heterostructures have attracted the attention of scientists worldwide for their greatly enhanced photocatalytic performance. Overall, this review summarizes the recent advances of g-C3N4-based nanocomposites modified with transition metal sulfide (TMS), including (1) preparation of pristine g-C3N4, (2) modification strategies of g-C3N4, (3) design principles of TMS-modified g-C3N4 heterostructured photocatalysts, and (4) applications in energy conversion. What is more, the characteristics and transfer mechanisms of each classification of the metal sulfide heterojunction system will be critically reviewed, spanning from the following categories: (1) Type I heterojunction, (2) Type II heterojunction, (3) p-n heterojunction, (4) Schottky junction and (5) Z-scheme heterojunction. Apart from that, the application of g-C3N4-based heterostructured photocatalysts in H2 evolution, CO2 reduction, N2 fixation and pollutant degradation will also be systematically presented. Last but not least, this review will conclude with invigorating perspectives, limitations and prospects for further advancing g-C3N4-based heterostructured photocatalysts toward practical benefits for a sustainable future.

Single Au Atoms Anchored on Amino‐Group‐Enriched Graphitic Carbon Nitride for Photocatalytic CO2 Reduction

“…Au single atoms on amino‐group‐enriched graphitic carbon nitride (U‐ACN) was synthesized through a mild and eco‐friendly urea reduction method (Figure a; see experimental details in the Supporting Information). The mixture of melamine and urea was calcined at 550 °C in air for 4 h, which led to the formation of graphitic carbon nitride (CN) through polycondensation . Then, urea, acting as the pH regulator, was added to the suspension of CN and HAuCl 4 in an 80 °C oil bath to facilitate the formation of Au‐containing precipitate AuCl 4− j (OH) j on CN .…”

Nanostructured CdS for efficient photocatalytic H2 evolution: A review

“…They found that the formation of Z-scheme heterostructures between ZnO and CdS could effectively prolong the lifetime of photogenerated e − , reaching a 14-fold improvement in H 2 evolution performance compared with that of pure CdS. Since then, numerous direct Z-scheme CdS-based photocatalysts have been applied in photo-catalytic H 2 generation applications [334], including CdS/ WO 3−x [222], FeC 2 O 4 •2H 2 O/CdS [335], CdS/WO 3 [165,301], CdS/MoO 3−x [336], CdS/g-C 3 N 4 [337,338], CoWO 4 /CdS [44], CdS/Fe 2 O 3 [179], CdS/BiVO 4 [339], TiO 2 /CdS [329,340,341], CdS/CdWO 4 [219,342], ZnO/ CdS [306] and CdS/PI [217]. In our previous study, we reported the fabrication of 2D/2D CdS/g-C 3 N 4 direct Zscheme heterojunction nanocomposites through the insitu growth of 2D CdS NSs on 2D g-C 3 N 4 NSs [338].…”

Solar‐Inspired Water Purification Based on Emerging 2D Materials: Status and Challenges

“…In recent years, g‐C 3 N 4 photocatalysts with Z‐scheme heterojunction have gained extensive attention due to its special charge transfer mechanism in degrading the organic pollutants, which can prominently enhance the photocatalytic efficiency . The advantages of Z‐scheme photocatalysts are: construction cost reduction, electron–hole separation efficiency improvement, removal of light‐shielding effect, and redox ability optimization .…”