S NAVEEN KUMAR
Articles written in Bulletin of Materials Science
Volume 43 All articles Published: 25 February 2020 Article ID 0084
In this work, we report a facile route for the synthesis of worm-like mesoporous Fe$_2$O$_3$-doped TiO$_2$ monolithic composites through a direct template sol–gel method, for the photocatalytic degradation of textile dye (acid blue 113) pollutants. The monolith surface morphology and structural properties have been characterized using p-XRD, HR-SEM–EDAX, HR-TEM–SAED, TGA, UV–Vis–DRS, PLS, FTIR, XPS and BET analyses. The stoichiometric doping of Fe$_2$O$_3$ unleashes visible light photocatalytic activity through a red shift in the light absorption character of TiO$_2$, thereby narrowing the energy band gap, and an eventual increase in e$^−$$/$h$^+$ separation centres. The monolithic photocatalyst exhibits better properties in terms of surface area, pore volume and diameter. The physico-chemical parameters, such as solution pH, dopant stoichiometry, catalyst quantity, dye concentration, photo-sensitizers and light intensity have been optimized to enhance the photocatalysis efficiency. The photocatalyst exhibits complete dye mineralization within 0.5 h, and also reusable for five continuous cycles.
Volume 44 All articles Published: 17 April 2021 Article ID 0099
We report the first of its kind synthesis of CeO$_2$/La$_2$O$_3$ nanocomposites that are with integrated mesoporous TiO$_2$ monoliths, with well-defined structural and surface properties, to act as visible-light responsive photocatalysts. Thes tructural features of the photocatalyst materials are defined using HR-TEM, p-XRD, FE-SEM, SAED, EDAX, XPS, PLS, TGA, IR, UV–Vis–DRS and BET/BJH analyses. The stoichiometric infusion of CeO$_2$/La$_2$O$_3$ nanocomposites with themonolithic TiO$_2$ network reduces the bandgap energy from 3.26 to 2.52 eV, thus promoting excellent visible-light photocatalysis. To evaluate the photocatalytic efficiency of the proposed photoactive materials, two antimicrobial drugs namely, moxifloxacin and ciprofloxacin are selected as target pollutants. It is observed that the uniform and continuous porous monolithic network ensures easy transport of pollutant molecules to the photoactive sites, thereby felicitating their faster dissipation. The influence of various physico-chemical parameters has been studied by photolysis and photocatalysis procedures, and the extent of drug degradation is quantitatively analysed by using a robust HPLC-DAD method. The photocatalysis results reveal that the monolithic photocatalyst can serve efficiently for environmental remediation applications, with excellent reusability character.
Volume 44, 2021
Continuous Article Publishing mode
Prof. Subi Jacob George — Jawaharlal Nehru Centre for Advanced Scientific Research, Jakkur, Bengaluru
Chemical Sciences 2020
Prof. Surajit Dhara — School of Physics, University of Hyderabad, Hyderabad
Physical Sciences 2020
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