Recent Advances in g‐C₃N₄‐Based Photocatalysts for Pollutant Degradation and Bacterial Disinfection: Design Strategies, Mechanisms, and Applications

Abstract

Rhodamine B (RhB), and methyl orange (MO), are highly toxic and can directly negatively affect the ecosystem and human health through water circulation. Pathogens, such as fungi and bacteria, can disrupt aquatic ecosystems and are closely linked to the incidence of epidemics. [2][3][4][5][6] In developing countries, it is estimated that about 80% of diseases are caused by water-borne pathogens. The abuse of antibiotics has led to their accumulation in the environment, which have given rise to antibiotic-resistant bacteria, and ultimately led to incurable infections that have increased death rates around the world; [7,8] therefore, the effective treatment of organic dye, pathogen, and antibiotic pollutants is a major environmental remediation task.At present, photocatalysis technology can convert solar energy into electric energy, chemical energy, etc., so that solar energy can be directly applied to environmental catalysis, energy catalysis, organic catalysis, sensing, biological imaging, electrochemical energy storage, and other fields. [9] It is considered one of the sustainability strategies to address future environmental crises. [10][11][12] The development of photocatalytic materials determines the progress in photocatalytic technologies. In 1972, Fujishima and Honda [13] used a TiO 2 -modified electrode to decompose water by direct photocatalysis using UV light, which was a milestone that initiated the development of photocatalytic materials. Then, Carey et al. [14] used TiO 2 powder to degrade organic pollutants, which further stimulated researchers' interest in photocatalytic materials. Since then, the development, modification, application, and catalytic mechanism of semiconductor photocatalytic materials represented by TiO 2 have made considerable progress. As research in this field progressed, it was found that the performance of photocatalytic materials mainly depends on the light absorption and electronhole separation efficiency of the photocatalyst; however, due to their wide bandgap, traditional TiO 2 photocatalysts can only use UV light with wavelengths below 387 nm, which account for 5% of the solar energy. To realize the maximum solar energy efficiency, researchers have made many attempts to modify TiO 2 -based photocatalysts. Although the spectral response range and the availability of solar energy have been improved slightly, there are still problems, such as high costs and heavy metal pollution; therefore, a popular research direction has Emerging photocatalytic technology promises to provide an effective solution to the global energy crisis and environmental pollution. Graphite carbon nitride (g-C 3 N 4 ) has gained extensive attention in the scientific community due to its excellent physical and chemical properties, attractive electronic band structure, and low cost. In this paper, research progress in design strategies for g-C 3 N 4 -based photocatalysts in the past five years is reviewed from the perspectives of nanostructure construction, element doping, and heterostructure construction...

Point‐to‐face contact heterojunctions: Interfacial design of 0D nanomaterials on 2D g‐C3N4 towards photocatalytic energy applications

“…12 Meanwhile, g-C 3 N 4 has a CB level of around −1.1 eV (vs. a normal hydrogen electrode [NHE]) and a VB level of around +1.6 eV (vs. an NHE at pH 7), 65,69,76 allowing it to perform well in a diverse range of photocatalytic reactions such as water splitting, [76][77][78][79] CO 2 reduction, 72,80,81 and degradation of organic pollutants. 82,83 Despite all these favorable characteristics of g-C 3 N 4 , the actual application of pristine g-C 3 N 4 is still hindered by a couple of problems. One of the problems is weak light absorption.…”

“…From the standpoint of thermodynamics, the locations of the VB and CB of a semiconductor, which govern the reduction and oxidation efficiency of photogenerated carriers, are also crucial for the process of artificial photoredox reactions 12 . Meanwhile, g‐C 3 N 4 has a CB level of around −1.1 eV (vs. a normal hydrogen electrode [NHE]) and a VB level of around +1.6 eV (vs. an NHE at pH 7), 65,69,76 allowing it to perform well in a diverse range of photocatalytic reactions such as water splitting, 76–79 CO 2 reduction, 72,80,81 and degradation of organic pollutants 82,83 …”

Recent advances in electron manipulation of nanomaterials for photoelectrochemical biosensors

“…107 Due to the well matched energy levels of BiOI and C 3 N 4 , BiOI microspheres were introduced to the compound with C 3 N 4 to form the BiOI/g-C 3 N 4 composite as a sensing substrate. 108,109 Thanks to the prominent charge conduction properties of the fabricated nanocomposites, the cathodic photocurrent was obviously amplified, thus resulting in broadening of the detection range to a great extent. Using CEA as a model analyte, a competitive PEC biosensing system was designed.…”

New strategies in the preparation of binary g-C3N4/MXene composites for visible-light-driven photocatalytic applications

“…Regardless, efforts have been made to optimize its photoelectric properties, and increase visible spectrum absorption and charge separation efficiency [14]. Therefore, several experiments have been designed to increase the efficiency of g-C3N4 by making binary or ternary composites with compounds such as BiVO 4 , InVO 4 , AgVO 3 , V 2 O 5 , TiO 2 , and ZnO [15][16][17][18][19]. Another strategy that has been significantly explored is the non-metallic elemental doping of O, S, N, and P, which are used as cocatalysts.…”