Fabrication of Naturally Derived Chitosan and Ilmenite Sand-Based TiO[sub.2]/Fe[sub.2]O[sub.3]/Fe-N-Doped Graphitic Carbon Composite for Photocatalytic Degradation of Methylene Blue under Sunlight

• Published in: Molecules (Basel, Switzerland) Switzerland), 2023-04, Vol.28 (7)
• Main Authors: Mendis, Amavin, Thambiliyagodage, Charitha, Ekanayake, Geethma, Liyanaarachchi, Heshan, Jayanetti, Madara, Vigneswaran, Saravanamuthu
• Format: Article
• Language: English
• Subjects: Chemical properties; Chitin; Graphite; Ilmenite; Methods; Methylene blue; Optical properties; Photocatalysis
• ISSN: 1420-3049; 1420-3049
• DOI: 10.3390/molecules28073154

Fabrication of chitosan and ilmenite sand-based novel photocatalysts through the catalytic graphitization of chitosan is reported. Nanocomposites consisted of TiO[sub.2] , Fe[sub.2] O[sub.3] and Fe nanoparticles dispersed on a nitrogen-doped graphitic carbon framework. The surface area, pore volume and macropore structure of the carbon matrix is disturbed by the heterogeneously distributed nanoparticles. The extent of graphitization expanded with increasing metal loading as indicated by variation in the ID/IG ratio. The nanomaterial’s surface consists of Fe[sup.3+] and Ti[sup.4+] , and graphitic, pyridinic and pyrrolic nitrogen were found in the carbon matrix. The band gap values of the composites varied in the 2.06–2.26 eV range. The photocatalytic activity of the synthesized nanomaterials was determined, and the highest rate constant for the photodegradation of methylene blue under sunlight was 4.4 × 10[sup.−3] min[sup.−1] , which resulted with 10 mg/L MB and 25 mg of the best-performing catalyst. The rate constant rose with increasing concentrations of persulfate added to the medium. The rate constant greatly diminished with the addition of isopropyl alcohol as it scavenged hydroxyl radicals. The presence of co-pollutants including Pb[sup.2+] , rhodamine B, PO[sub.4] [sup.3−] and Cl[sup.−] curtailed the rate of reaction. The activity reduced with an increasing number of uses of the catalyst.