Metal-free n/n–junctioned graphitic carbon nitride (g-C3N4): a study to elucidate its charge transfer mechanism and application for environmental remediation
2021
Phang, Sue Jiun | Goh, Jin Mei | Tan, Lling-Lling | Lee, Wuen Pei Cathie | Ong, Wee-Jun | Chai, Siang-Piao
Graphitic carbon nitride (g-C₃N₄) has been regarded as a promising visible light–driven photocatalyst ascribable to its tailorable structures, thermal stability and chemical inertness. Enhanced photocatalytic activity is achievable by the construction of homojunction nanocomposites to reduce the undesired recombination of photogenerated charge carriers. In the present work, a novel g-C₃N₄/g-C₃N₄ metal-free homojunction photocatalyst was synthesized via hydrothermal polymerization. The g-C₃N₄/g-C₃N₄ derived from urea and thiourea demonstrated admirable photocatalytic activity towards rhodamine B (RhB) degradation upon irradiation of an 18 W LED light. The viability of the photoreaction with a low-powered excitation source highlighted the economic and environmental benefits of the process. The optimal g-C₃N₄/g-C₃N₄ homojunction photocatalyst exhibited a 2- and 1.8-fold increase in efficiency in relative to pristine g-C₃N₄ derived from urea and thiourea respectively. The enhanced photocatalytic performance is credited to the improved interfacial transfer and separation of electron-hole pairs across the homojunction interface. Furthermore, an excellent photochemical stability and durability is displayed by g-C₃N₄/g-C₃N₄ after three consecutive cycles. In addition, a plausible photocatalytic mechanism was proposed based on various scavenging tests. Overall, experimental results generated from this study is expected to intrigue novel research inspirations in developing metal-free homojunction photocatalysts to be feasible for large-scale wastewater treatment without compromising economically. Graphical abstract
Show more [+] Less [-]AGROVOC Keywords
Bibliographic information
This bibliographic record has been provided by National Agricultural Library
