The Department of Physics is pleased to announce that Professor Ranjit Thapa, Dean-School of Engineering and Sciences (SEAS) and Professor of Physics along with his PhD scholar, Mr E S Erakulan, has published a groundbreaking paper titled “Scrutinizing the Role of Tunable Carbon Vacancies in g-C3N4 Nanosheets for Efficient Sonophotocatalytic Degradation of Tetracycline in Diverse Water Matrices: Experimental study and theoretical calculation” in the prestigious Chemical Engineering Journal with an impact factor of 16.744. The paper offers crucial insights into the role of controllable defects in the sonophotocatalytic degradation of tetracycline (TC) antibiotics from polluted water.
Abstract of the paper
Metal-free polymeric graphitic carbon nitride (CN) materials are robust and stable visible-light-driven photocatalysts that have recently piqued interest in photocatalytic applications. Its photocatalytic performance is restricted remarkably due to moderate oxidation ability and fast charge carrier recombination rate. To address these issues, we engineered carbon-vacant CN (FCN) using a facile formalin-assisted thermal polymerization of molten CN precursor in which the carbon vacancies (C v ) were regulated by altering formalin dosage. Consequently, FCN catalysts revealed C v concentration-dependent sonophotocatalytic degradation of Tetracycline (TC) antibiotics over diverse water matrices. The optimal FCN exhibited complete TC degradation efficiency within 60 min with a synergy index of 1.4, which is approximately 2.6 times higher than that of pristine CN. The enhanced sonophotocatalytic performance was mainly due to the synergistic effect of ultrasound and light irradiation. The C v formation also resulted in enhanced charge carrier transportation and facilitated oxygen adsorption at the C V site of FCN – supported by both experimental study and theoretical calculation. Subsequently, FCN generated abundant reactive active oxygen species including, •O 2 –, as well as indirectly •OH which played a significant role in the degradation pathway and mineralisation of the TC molecules. This study provides insight into understanding the correlation between controllable defects and sonophotocatalytic degradation properties of the self-doped and deficient FCN.
In this research, Prof. Thapa and his team utilised a facile formalin-assisted thermal polymerization technique to fabricate metal-free polymeric graphitic carbon nitride (CN) materials. These materials have been gaining increasing interest as photocatalysts, although their photocatalytic performance has been restricted due to moderate oxidation ability and fast charge carrier recombination rate. To address these issues, the researchers engineered carbon-vacant CN (FCN) by regulating carbon vacancies (Cv) with formalin dosage. The optimal FCN catalyst exhibited complete TC degradation within 60 minutes with a synergy index of 1.4, which is approximately 2.6 times higher than pristine CN.
Emerging pollutants, such as antibiotics discharged from pharmaceutical companies, have detrimental effects on living organisms and can cause drug resistance through gene transmission. The removal of TC from water requires efficient and sustainable strategies. A detailed understanding of the synergistic effects of the defect and self-doped CN in sonophotocatalytic degradation could pave the way for the destruction of various recalcitrant pollutants in an aqueous environment.
Collaborations
- Ms Mani Preeyanghaa, Department of Physics and Nanotechnology, SRM Institute of Science and Technology, Kattankulathur, Chennai.
- Prof. Bernaurdshaw Neppolian, Department of Physics and Nanotechnology, SRM Institute of Science and Technology, Kattankulathur, Chennai.
Overall, the research presents exciting possibilities for future projects in the field of sonophotocatalytic degradation and provides a significant contribution to the scientific community’s understanding of controllable defects in CN materials.