resumo
A new composite of TiO2 (P25) and N-doped carbon quantum dots (P25/NCQD) was prepared by a hydrothermal method and was used for the first time as catalyst of the photo-oxidation of NO under UV and visible light irradiation. P25/NCQD composite exhibited a NO conversion (27.0%) more than two times higher of that observed for P25 (10%) under visible light and the selectivity of the process was increased from 37.4% to 49.3%. The composite also showed better photocatalytic performance than P25 in the UV region with increases of 36.3% on NO conversion and 16.8% on selectivity. Moreover, compared with P25, the photodegradation ratio of methylene blue was enhanced from 68% to 91% after UV irradiation for 1 h. NCQD played a crucial role on the photocatalytic activity improvement of P25/NCQD, increasing visible light absorption, slowing the recombination and improving the charge transfer. (C) 2016 The Authors. Published by Elsevier B.V.
palavras-chave
MICROWAVE-ASSISTED PYROLYSIS; ONE-STEP SYNTHESIS; VISIBLE-LIGHT; NOX ABATEMENT; TIO2 PHOTOCATALYSIS; METHYLENE-BLUE; NITRIC-OXIDE; DOTS; DEGRADATION; REMOVAL
categoria
Chemistry; Engineering
autores
Martins, NCT; Angelo, J; Girao, AV; Trindade, T; Andrade, L; Mendes, A
nossos autores
Grupos
G1 - Materiais Porosos e Nanossistemas
G3 - Materiais Eletroquímicos, Interfaces e Revestimentos
agradecimentos
Luisa Andrade and Natercia Martins acknowledge the European Research Council for funding within project BI-DSC-Building Integrated Dye sensitized Solar Cells (Contract Number: 321315). This work was also supported by research project SolarConcept (PTDC/EQU-EQU/120064/2010), co-financed by the European Union and the Portuguese Government through the Portuguese Foundation for Science and Technology (FCT), in the framework of the QREN Initiative and the European Regional Development Fund through the Operational Program for Competitiveness Factors. Ana Girdo and Tito Trindade thank the project CICECO-Aveiro Institute of Materials (Ref. FCT UID/CTM/50011/2013), financed by national funds through the FCT/MEC and when appropriate co-financed by FEDER under the PT2020 Partnership Agreement. Joana Angelo is grateful to the Portuguese Foundation for Science and Technology (FCT) for her Ph.D grant (SFRH/BD/79974/2011). Ana Girao thanks FCT for funding her Postdoctoral Research Grant (SFRH/BPD/66407/2009) and acknowledges Dr. Nuno Joao for XRD acquisition. The authors are thankful to CEMUP for the XPS analysis.