Metal-Doped Graphitic Carbon Nitride Nanomaterials for Photocatalytic Environmental Applications—A Review

Abstract

In the current world situation, population and industrial growth have become major problems for energy and environmental concerns. Extremely noxious pollutants such as heavy metal ions, dyes, antibiotics, phenols, and pesticides in water are the main causes behind deprived water quality leading to inadequate access to clean water. In this connection, graphite carbon nitride (GCN or g-C3N4) a nonmetallic polymeric material has been utilized extensively as a visible-light-responsive photocatalyst for a variety of environmental applications. This review focuses on recent developments in the design and photocatalytic applications of metal-doped GCN-based nanomaterials in CO2 photoreduction, water splitting toward hydrogen production, bacterial disinfection, and organic pollutant degradation. Additionally, this review discusses various methods of using GCN-based materials to optimize dye sensitization, metal deposition, ion doping, and their environmental applications.

Recent Advances on g‐C3N4 Based Photocatalysts for Typical Antibiotics Photodegradation: Preparation, Mechanism and Influencing Factors

“…There are many advantages of metal element doping of g-C 3 N 4 , firstly, metal doping in pure g-C 3 N 4 can interact with cations to generate lone electron pairs, which strengthens the electron trapping ability. [56] Moreover, metal-doping can regulate the (2 h) [76] morphology and crystalline phase of g-C 3 N 4 effectively, thereby enhancing the photocatalytic efficiency of the catalyst by building a non-homogeneous structure. Zhao et al introduced various ratios of cadmium into porous g-C 3 N 4 photocatalysts with higher electrical conductance, superior light absorption properties and photogenerated e + -h À pair migration efficiency, which significantly strengthened their photocatalytic activity.…”

“…Introducing metal elements into g‐C 3 N 4 skeleton can effectively improve transfer and separation of charges, which is a tactic to improve photo‐catalytic performance [56] . Zong et al.…”

“…There are many advantages of metal element doping of g‐C 3 N 4 , firstly, metal doping in pure g‐C 3 N 4 can interact with cations to generate lone electron pairs, which strengthens the electron trapping ability [56] . Moreover, metal‐doping can regulate the morphology and crystalline phase of g‐C 3 N 4 effectively, thereby enhancing the photocatalytic efficiency of the catalyst by building a non‐homogeneous structure.…”

“…Introducing metal elements into g-C 3 N 4 skeleton can effectively improve transfer and separation of charges, which is a tactic to improve photo-catalytic performance. [56] Zong et al synthesized a unique W-doped foam plastic g-C 3 N 4 , improved the electronic structure of g-C 3 N 4 , increased the specific surface area, and enhanced the photocatalytic degradation performance of RhB. Liu et al made a K-doped ZnO/g-C 3 N 4 composite photocatalytic material.…”

Anion–Cation Co-Doped g-C3N4 Porous Nanotubes with Efficient Photocatalytic H2 Evolution Performance

“…In addition, various existing researches have proven that implanting the anion–cation into the g-C 3 N 4 frameworks could regulate their bandgap structure for broader visible-light absorption, facilitate the bulk phase and interface charge separation and lead to enhanced photocatalytic activity for H 2 evolution [ 21 , 22 , 23 ]. For instance, Qiao et al [ 24 ] found that a new intermediate energy level was formed in the bandgap of g-C 3 N 4 via the insertion of P into its skeleton, which received the electrons generated by light excitation from VB and thus improved the separation of photocarriers.…”