Autor(es)

Rahman, Kifayat U. ; Ferreira-Neto, Elias P. ; Rahman, Ghaws U. ; Parveen, Rashida ; Monteiro, Andreia S. ; Rahman, Gul ; Quyet Van Le ; Domeneguetti, Rafael R. ; Ribeiro, Sidney J. L. ; Ullah, Sajjad

• Tipo de documento: Artigo Científico
• Fonte: JOURNAL OF ENVIRONMENTAL CHEMICAL ENGINEERING; v. 9, n. 1, p. 12-pg., 2021-01-24.

Resumo

This research study reports the formation of flexible and multifunctional organic-inorganic hybrid membranes (BC-SiO2-TiO2/Ag) based on bacterial cellulose (BC) that contain photoactive (TiO2) and antibacterial (Ag) components, rendering them photocatalytic, self-cleaning and UV-shielding properties (due to TiO2) as well as antibacterial activity. Coating of BC with sol-gel derived silica and titania particles was achieved through hydrolysis-polycondensation of tetraethyl orthosilicate and titanium (IV) isopropoxide, respectively, and a soft hydrothermal treatment (140 degrees C, 20 h) was used to obtain well-crystalline TiO2. The prepared BC-SiO2-TiO2/Ag photoactive membranes were characterized by an array of analytical techniques including XRD, XRF, SEM-EDS, electronic absorption spectroscopy and vibrational spectroscopy. The morphology of TiO2 coatings changes from a homogenous film-like smooth one to a rougher one consisting of randomly oriented titania particles (170 +/- 35 nm) upon increasing the TiO2 loading of the membranes. These prepared photoactive BC-SiO2-TiO2 membranes exhibited excellent TiO2-loading dependent photocatalytic/self-cleaning activity towards crystal violet dye deposited as an over-layer on the surface of the membranes, degrading 97 % of the dye within 50 min of UV illumination. In addition to good photoactivity, the BC-SiO2-TiO2/Ag membranes demonstrated reasonable antibacterial activity against five different bacterial strains under dark conditions. These flexible BC-based hybrid membranes with photocatalytic, self-cleaning, antibacterial properties have the potential to be used in the design of self-cleaning and antibacterial surfaces, filters and facemasks that could be easily disinfected under UV irradiation from a lamp or natural sunlight and safely discarded and even recycled. (AU)

• Processo FAPESP: 18/01934-0 - Aerogéis de dissulfetos de metais de transição e celulose bacteriana: nanomateriais bifuncionais com propriedades fotocatalíticas e adsortivas para aplicações ambientais
• Beneficiário: Elias Paiva Ferreira Neto
• Modalidade de apoio: Bolsas no Brasil - Pós-Doutorado