Recent Developments in Graphitic Carbon Nitride Based Hydrogels as Photocatalysts

Abstract

Solar‐driven photocatalysis with graphitic carbon nitride (g‐C3N4) is considered to be the most promising approach for the generation of H2 from water, the degradation of organic pollutants, and the reduction of CO2. However, bulk g‐C3N4 exhibits several drawbacks, such as a low specific surface area, high defect density, and fast charge recombination, which result in low photocatalytic performance. The construction of 3D porous hydrogels for g‐C3N4 through nanostructural engineering is a rapid, feasible, and cost‐effective technique to improve the adsorption capability, stability, and separability of the hydrogel composite; to increase the number of active sites; and to create an internal conductive path for facile charge transfer and high photocatalytic activity. This minireview summarizes recent progress in photocatalytic water splitting and dye degradation by using g‐C3N4‐based hydrogels, with respect to state‐of‐the‐art methods for synthesis, preparation, modification, and multicomponent coupling. Furthermore, comprehensive outlooks, future challenges, and concluding remarks regarding the use of g‐C3N4‐based hydrogels as highly efficient photocatalysts are presented.

Graphitic carbon nitride and polymers: a mutual combination for advanced properties

“…Most notably, these hydrogels incorporate g-C 3 N 4 , which might have various effects on materials properties. 189 For example, g-C 3 N 4based hydrogels feature remarkable mechanical properties like compressibility and high storage moduli as discussed in Section 5.1. In addition, g-C 3 N 4 -based hydrogels retain the photocatalytic properties of g-C 3 N 4 , which allows utilization in contaminant degradation or H 2 evolution (Section 5.2).…”

Influence of Ag nanoparticles anchored on protonated g-C3N4–Bi2MoO6 nanocomposites for effective antibiotic and organic pollutant degradation

“…19,20 Besides this, g-C 3 N 4 contains abundant functional groups such as carbon (C) and nitrogen (N), which augment the material properties to boost its broad specic area housing active absorption sites for organic pollutants. 21,22 Meanwhile, there have been few attempts on investigating noble metals anchored on heterojunction semiconductors to reduce the band gap energy. Indeed, g-C 3 N 4 has certain limitations in realistic photocatalysis applications, such as inadequate real surface area, less separation of photoexcited electron-hole pairs, limited electron transfer, poor quantum yield, and low light-harvesting ability.…”

Photoinduced post-modification of graphitic carbon nitride-embedded hydrogels: synthesis of 'hydrophobic hydrogels' and pore substructuring

“…Integration of g-CN into hydrogels has been popularized in the last four years, where g-CN nanosheets can be implemented into hydrogels through embedding [ 36 ] or covalent binding [ 37 – 38 ] for the target application such as reinforced hydrogels [ 39 ] and hydrogels for photoredox-based applications [ 40 – 41 ].…”