abstract
Modern life-style is creating an indoor generation: human beings spend approximately 90% of their time indoors, almost 70% of which is at home - this trend is now exacerbated by the lockdowns/restrictions imposed due to the COVID-19 pandemic. That large amount of time spent indoors may have negative consequences on health and well-being. Indeed, poor indoor air quality is linked to a condition known as sick building syndrome. Therefore, breathing the freshest air possible is of outmost importance. Still, due to reduced ventilation rates, indoor air quality can be considerably worse than outdoor. Heating, ventilation, and air conditioning (HVAC), air filtration systems and a well-ventilated space are a partial answer. However, these approaches involve only a physical removal. The photocatalytic mineralization of pollutants into non-hazardous, or at least less dangerous compounds, is a more viable solution for their removal. Titanium dioxide, the archetype photocatalytic material, needs UVA light to be 'activated'. However, modern household light emitting diode lamps irradiate only in the visible region of the solar spectrum. We show that the surface of titanium dioxide nanoparticles modified with copper oxide(s) and graphene has promise as a viable way to remove gaseous pollutants (benzene and nitrogen oxides) using a common light emitting diode bulb, mimicking real indoor lighting conditions. Titanium dioxide, modified with 1 mol% CuxO and 1 wt% graphene, proved to have a stable photocatalytic degradation rate, three times higher than that of unmodified titania. Materials produced in this research work are thus strong candidates for offering a safer indoor environment. (C) 2022 Elsevier Ltd. All rights reserved.
keywords
TIO2; TECHNOLOGIES; ABSORPTION; CONVERSION; TOLUENE; ENERGY
subject category
Chemistry; Energy & Fuels; Materials Science
authors
Tobaldi, DM; Dvoranova, D; Lajaunie, L; Czikhardtova, K; Figueiredo, B; Calvino, JJ; Seabra, MP; Labrincha, JA
our authors
acknowledgements
This work was partly developed within the scope of the bilateral project between Portugal and the Slovak Republic, FCT/484/January 15, 2019/S, and in the frame of the project CICECO-Aveiro Institute of Materials, UIDB/50011/2020 & UIDP/50011/2020, financed by national funds through the Portuguese Foundation for Science and Technology/MCTES. This research was also partly financially sup-ported by the Scientific Grant Agency of the Slovak Republic (VEGA Project 1/0064/21) , and Slovak Research and Development Agency under the contract No. SK-PT-2018-0007. David Maria Tobaldi is currently funded by the project EleGaNTe-PONARS01_01007, yet has been grateful to FCT and Portuguese national funds (OE) , through FCT, I.P., in the scope of the framework contract foreseen in the numbers 4, 5 and 6 of the article 23, of the Decree-Law 57/2016, of August 29, changed by Law 57/2017, of July 19. Luc Lajaunie gratefully acknowledges the support from the Andalusian regional government (FEDER-UCA-18-106613) , and that of the Spanish Ministerio de Economia y Competitividad (PID2019-107578 GA-I0 0) . This project has also received partial funding from the Euro-pean Union's Horizon 2020 research and innovation programme under grant agreement No 823717-ESTEEM3. Dana Dvoranova? thanks the Ministry of Education, Science, Research and Sport of the Slovak Republic for funding within the scheme Excellent research teams. Prof Vlasta Brezov?a (Slovak University of Technology in Bratislava) is heartfully acknowledged for the fruitful discussion. Last but not less important, we are very much obliged to Miss Dafne Maria Glaglanon for proof-editing the English of the manuscript.