Crystallinity and lattice vacancies of different mesoporous g-C3N4 for photodegradation of tetracycline and its cytotoxic implication
Document Type
Article
Publication Date
12-1-2022
Abstract
Tetracycline (TC) antibiotic removal from water bodies is important to provide clean water and sanitation. Mesoporous graphitic carbon nitride (GCN) photocatalyst derived from three different types of precursors manages to remove TC effectively under visible light irradiation. Among urea, thiourea, and melamine precursors, melamine-prepared GCN (MGCN) via thermal polymerization has the highest efficiency to photodegrade tetracycline (TC) antibiotics up to 99.5% (0.0122 min(-1)) within 240 min. The COD for TC removal by using MGCN was up to 77.5% after 240 min of degradation. This is due to the slow charge recombination and rapid charge carrier migration. The MGCN encounters different properties such as high crystallinity, dense structure allowing fast charges migration, and nitrogen vacancies that create a defect state that suppresses charge recombination. It was found that the conduction band (CB) of MGCN was located at a more negative position (E-CB = -0.33 V) than (O-2/O-2(center dot-)) and the valence band (VB) was placed at a more positive position (E-VB = 2.30 V) than (H2O/OH center dot), which allows generation of both radicals for photodegradation. Based on the cell viability test, the photodegraded TC in the water how non-toxicity toward Balb/c 3T3 cells after being irradiated (lambda > 420 nm) for 240 min under visible light. The MGCN prepared in this study demonstrated the highest effectiveness and recyclable photocatalyst for the removal of TC among all GCNs.
Keywords
Antibiotics, Cytotoxic test, Graphitic carbon nitride, Mesoporous, Photocatalyst, Tetracycline
Divisions
nanotechnology
Funders
Ministry of Education, Malaysia [FRGS/1/2021/STG05/UM/02/3],Universiti Malaya, Malaysia [PPSI-2020-CLUSTER-IDIG03],Institute of Research and Management of Universiti Malaya
Publication Title
Chemosphere
Volume
308
Issue
1
Publisher
Elsevier
Publisher Location
THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLAND