Influence of rapid heat treatment on the photocatalytic activity and stability of calcium titanates against a broad range of pollutants
Mahsa Abedi,
Zsejke-Réka Tóth,
Milica Todea,
Áron Ágoston,
Ákos Kukovecz,
Zoltán Kónya,
Zsolt Pap,
Tamás Gyulavári
Affiliations
Mahsa Abedi
Department of Applied and Environmental Chemistry, University of Szeged, Rerrich Béla Sqr. 1, 6720, Szeged, Hungary
Zsejke-Réka Tóth
Doctoral School of Physics, Babes-Bolyai University, M. Kogălniceanu 1, 400084, Cluj-Napoca, Romania; Nanostructured Materials and Bio-Nano-Interfaces Center, Interdisciplinary Research Institute on Bio-Nano-Sciences, Babes-Bolyai University, T. Laurian 42, 400271, Cluj-Napoca, Romania
Milica Todea
Nanostructured Materials and Bio-Nano-Interfaces Center, Interdisciplinary Research Institute on Bio-Nano-Sciences, Babes-Bolyai University, T. Laurian 42, 400271, Cluj-Napoca, Romania; Faculty of Medicine, Iuliu Hațieganu University of Medicine and Pharmacy, Victor Babeș 8, 400012, Cluj-Napoca, Romania
Áron Ágoston
Department of Applied and Environmental Chemistry, University of Szeged, Rerrich Béla Sqr. 1, 6720, Szeged, Hungary; Department of Physical Chemistry and Materials Sciences, University of Szeged, Aradi v. Sqr. 1, 6720, Szeged, Hungary
Ákos Kukovecz
Department of Applied and Environmental Chemistry, University of Szeged, Rerrich Béla Sqr. 1, 6720, Szeged, Hungary
Zoltán Kónya
Department of Applied and Environmental Chemistry, University of Szeged, Rerrich Béla Sqr. 1, 6720, Szeged, Hungary
Zsolt Pap
Department of Applied and Environmental Chemistry, University of Szeged, Rerrich Béla Sqr. 1, 6720, Szeged, Hungary; Nanostructured Materials and Bio-Nano-Interfaces Center, Interdisciplinary Research Institute on Bio-Nano-Sciences, Babes-Bolyai University, T. Laurian 42, 400271, Cluj-Napoca, Romania; STAR-UBB Institute, Babes-Bolyai University, M. Kogălniceanu 1, 400084, Cluj-Napoca, Romania; Corresponding author. Department of Applied and Environmental Chemistry, University of Szeged, Rerrich Béla Sqr. 1, 6720, Szeged, Hungary.
Tamás Gyulavári
Department of Applied and Environmental Chemistry, University of Szeged, Rerrich Béla Sqr. 1, 6720, Szeged, Hungary; Corresponding author.
Calcium titanate (CTO) photocatalysts were synthesized using a sol–gel method by adopting a cost-efficient, rapid calcination technique. The CTOs were characterized by X-ray diffractometry, X-ray photoelectron spectroscopy, infrared spectroscopy, nitrogen adsorption, porosimetry measurements, scanning/transmission electron microscopy, and diffuse reflectance spectroscopy. Their photocatalytic activity was assessed through the photocatalytic degradation of phenol, oxalic acid, and chlorophenol under UV light exposure, using a commercial CTO as a reference. The stability of the samples was evaluated using compounds with –OH, –COOH, and –Cl functional groups. Characterization results showed that CTO composites containing anatase, rutile, and brookite titania were obtained. Increasing the calcination temperature led to various crystalline compositions, higher crystallinity, larger primary crystallite sizes, and smaller specific surface areas. The photocatalytic activity of all CTO/TiO2 composites was superior compared to the commercial CTO we used as a reference. The high photocatalytic activity of the best-performing composites was attributed to their higher specific surface areas and the synergistic effect between the crystal phases. A cost comparison was also made between our unique calcination technique and conventional calcination, and it was found that our method is approximately 35% more cost-effective, while retaining the photocatalytic activity.
