Photocatalytic degradation of organic dye under UV light using CaCu3Ti4O12 nanoparticles synthesized by sol gel route: Effect of calcination temperature

Abstract

The focus of this undertaking, is on the influence of calcination temperature (600 °C to 900 °C), on the features and photocatalytic (PC) performance, of sol–gel synthesized CaCu3Ti4O12 (CCTO) nanoparticles (NPs). The characterization of the structural, compositional, morphological, and optical properties, of the CCTO NPs, was achieved through several procedures. Photodegradation of cationic dye (rhodamine B-RhB) in aqueous solution, under ultraviolet (UV) light irradiation, was used to evaluate the PC performance of the NPs. According to the XRD results, all the calcined powders displayed a well-crystalline and cubic structure of CCTO. Using FTIR, the absorption bands, relating to the vibrations of Ca-O, Cu–O and Ti-O-Ti, were distinguished at 560, 520 and 430 cm − 1 respectively. Calcination brought about a decline, from 2.80 to 2.22 eV, in the optical bandgap energy (Eg) of the CCTO NPs, which can be put down to the increase in crystallinity. In terms of PC performance, the sample C900 displayed a greater photodegradation efficiency (59.4 % at 30 min), when compared to samples calcined at lower temperatures. Additionally, the C900 sample delivered outstanding results in recycle tests, in which it shed merely 8 % of efficiency in the fourth cycle. This consolidates the premise, that calcination generates highly photo-catalytically active CCTO.