| Full text | |
| Author(s): |
Moreira, Ailton J.
;
Coelho, Dyovani
;
Dias, Jeferson A.
;
Mascaro, Lucia H.
;
Freschi, Gian P. G.
;
Mastelaro, Valmor R.
;
Pereira, Ernesto C.
Total Authors: 7
|
| Document type: | Journal article |
| Source: | Journal of Alloys and Compounds; v. 905, p. 14-pg., 2022-02-16. |
| Abstract | |
The scientific community has been looking for strategies to synthesize active catalysts under Ultraviolet_Visible (UV_Vis) light to atrazine (ATZ) degradation. In this study, we applied for the first time the microwave (MW) energy and a Microwave Discharge Electrodeless Lamp (MDEL) as an UV_Vis light source to synthesize photocatalysts. The synergistic use of MW_UV_Vis energies allowed obtaining Smdoped TiO2 with photoactivity under UV-A light (365 nm) to degrade ATZ. Different characterization analyzes showed that Sm3+ was inserted into the TiO2 lattice and prevented the conversion of anatase into rutile, in addition to giving rise to brookite phase, which increase under MDEL assisted synthesis. Different techniques proved the doping, and especially photoluminescence (PL) showed that electrons are excited to f levels of Sm3+ and can be trapped in the structural defects of the photocatalyst to be consumed later. Moreover, the catalyst synthesized under MDEL irradiation (STiM) showed lower recombination rates and a performance to degrade ATZ of 45% and 15% higher than pristine TiO2 (Ti) and Sm-doped TiO2 (STi), respectively. Photocatalytic degradation mechanism was unveiled by monitoring Desethyl-atrazine (DEAT), Desisopropyl-atrazine (DIAT), and Hydroxy-atrazine (HAT), which are by-products of ATZ. The doped materials showed high efficiency to activate the ATZ hydrolysis reaction, while the water oxidation to generate & BULL;OH and converted ATZ to HAT was more pronounced in STiM. We proved through radical probe tests that STiM produces more hydroxyl radicals and that its photoactivity remains even after 4 application cycles. (C) 2022 Elsevier B.V. All rights reserved. (AU) | |
| FAPESP's process: | 14/50249-8 - Green chemistry: sustainable synthetic methods employing benign solvents, safer reagents, and bio-renewable feedstock |
| Grantee: | Arlene Gonçalves Corrêa |
| Support Opportunities: | Research Grants - Research Centers in Engineering Program |
| FAPESP's process: | 13/07296-2 - CDMF - Center for the Development of Functional Materials |
| Grantee: | Elson Longo da Silva |
| Support Opportunities: | Research Grants - Research, Innovation and Dissemination Centers - RIDC |
| FAPESP's process: | 17/11986-5 - Generation and storage of New Energy: bringing technological development for the country |
| Grantee: | Ana Flávia Nogueira |
| Support Opportunities: | Research Grants - Research Centers in Engineering Program |