Abstract
Towards the application of perovskite in photoelectrocatalytic oxidation of organic pollutants in water, bismuth ferrite (BiFeO3) was prepared by facile hydrothermal method and composited with graphite nanoparticles (GNPs) to form BiFeO3/GNPs composite. The photoanodes of BiFeO3, GNPs and BiFeO3/GNPs were fabricated on a fluorine doped tin oxide (FTO) glass substrate. The materials and photoanodes were characterised with X-ray diffractometry (XRD), field emission scanning electron microscopy (FESEM), transmission electron microscopy (TEM) and UV–vis diffuse reflectance spectroscopy (UV-DRS). Furthermore, the photoanodes were photoelectrochemically characterised by evaluating their photocurrent response and charge transfer resistance with impedance spectroscopy. Results confirmed that the visible light absorbance of BiFeO3 was enhanced by the addition of GNPs. The BiFeO3/GNPs showed marked enhancement in the photocurrent density and low charge transfer resistance over BiFeO3 owing to the excellent electrical conductivity of graphite nanoparticle. The photoelectrocatalytic performance of BiFeO3, GNPs and BiFeO3/GNPs photoanodes were studied through the degradation of ciprofloxacin in aqueous solution. Degradation percentages of 48 %, 50 % and 78 % were recorded for BiFeO3, GNPs and BiFeO3/GNPs after 4 h respectively. In addition, the total organic carbon (TOC) removal analysis showed 30 %, 38 % and 56 % for BiFeO3, GNPs and BiFeO3/GNPs respectively. The study showed the beneficial effect of doping BiFeO3 with graphite nanoparticles and also the synergy of electrochemical oxidation and photocatalysis in photoelectrocatalytic process performance. Degradation pattern and product studies, obtained from ultra performance liquid chromatography-tandem mass spectrometry (UPLC-MS) and scavenger studies data, showed that the degradation of ciprofloxacin was activated by the hydroxyl and hole radicals and it followed a direct oxidation of piperazine ring with other intermediate degradation products. The composite photoanode exhibited good stability and reusability.
Original language | English |
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Article number | 114275 |
Journal | Journal of Photochemistry and Photobiology A: Chemistry |
Volume | 434 |
DOIs | |
Publication status | Published - 1 Jan 2023 |
Keywords
- Bismuth ferrite
- Ciprofloxacin
- Graphite nanoparticles photoanode
- Photoelectrocatalytic degradation
- Ultra performance liquid chromatography-mass spectroscopy
- Water treatment
ASJC Scopus subject areas
- General Chemistry
- General Chemical Engineering
- General Physics and Astronomy