BIBLIOS

Document type
Journal articles

Document subtype
Full paper

Title
Novel C-dots/titanate nanotubular hybrid materials with enhanced optical and photocatalytic properties

Participants in the publication
D.M. Alves (Author)
J.V. Prata (Author)
A.J. Silvestre (Author)
O.C. Monteiro (Author)
Dep. Química e Bioquímica
CQE

Summary
Advanced nanomaterials with enhanced optical and photocatalytic properties for the photodegradation of organic pollutants, in particular pharmaceuticals and personal care products (PPCPs), were successfully prepared by a swift one-pot synthesis. Nanostructured materials were synthesized through an integrated hydrothermal procedure which generates titanate nanotubes (TNTs) with different carbon dots (C-dots) contents, from an amorphous titanium oxide-based source and cork industry wastewaters (CIWW) as carbon source. Their structural, microstructural, morphological, and optical properties were studied by XRD, TEM, XPS, UV-Vis diffuse reflectance and photoluminescence spectroscopies. As aimed, the hybrid C-dots/TNT nanomaterials extend their light absorption towards the red, in comparison to pristine TNT, prompting them for a more efficient use of light in photocatalysis by widening the TNT energy uptake range. The decrease of bandgap energy with increasing sample’s C-dots content seems to be originated from energy intermediate states formed within the TNTs’ forbidden band resulting from Ti−O−C bonds established between the TNTs and the C-dots that form tails of states.\\\\n\\\\nThe as-synthesized C-dots/TNT samples were tested in the photodegradation of caffeine as a pollutant model for PPCPs. Rewarding results were obtained, with the hybrid C-dots/TNT nanomaterials showing significant enhanced photocatalytic ability toward caffeine degradation in comparison to pristine TNTs. Photocatalysis assays in the presence of scavengers and/or in the absence of oxygen were also performed aiming to characterize the most reactive species formed during the semiconductor photo-activation process and thus assessing to possible reactive pathways underpinning the photocatalytic activity of the hybrid C-dots/TNT nanomaterials.


Where published
Journal of Alloys and Compounds

Publication Identifiers
ISSN - 0925-8388

Publisher
Elsevier BV



Document Identifiers
DOI - https://doi.org/10.1016/j.jallcom.2022.168143
URL - http://dx.doi.org/10.1016/j.jallcom.2022.168143

Rankings
Web Of Science Q1 (2023) - 5.8 - MATERIALS SCIENCE, MULTIDISCIPLINARY