TY - JOUR
T1 - Fabrication of visible-light-active ZnCr mixed metal oxide/fly ash for photocatalytic activity toward pharmaceutical waste ciprofloxacin
AU - Chuaicham, Chitiphon
AU - Inoue, Takumi
AU - Balakumar, Vellaichamy
AU - Tian, Quanzhi
AU - Sasaki, Keiko
N1 - Publisher Copyright:
© 2022 The Korean Society of Industrial and Engineering Chemistry
PY - 2022/4/25
Y1 - 2022/4/25
N2 - Visible active photocatalysts have attracted interest as a potentially efficient and sustainable approach for pollutant degradation treatment. In this work, ZnCr mixed metal oxide/fly ash (ZnCr-MMO/FA) composites were prepared using fly ash (FA) from China coal mining power plants to improve photocatalytic performance. The formation of the ZnCr-MMO/FA composites was proved by XRD results which showed the two-phases combination of FA and MMO. Also, the presence of FA in the ZnCr-MMO/FA composite provided a good arrangement of small particles of ZnCr-MMO on the surface of FA and higher light absorption ability with a lower energy bandgap compared with the pure ZnCr-MMO. The photocatalytic performance of the prepared ZnCr-MMO and ZnCr-MMO/FA composites in different FA contents was evaluated by degradation of ciprofloxacin (CIP), which is an antibiotic and often found in pharmaceutical wastes, under visible light irradiation. Clearly, the ZnCr-MMO/FA composites showed higher photocatalytic decomposition of CIP than pristine ZnCr-MMO, and the highest degradation performance for CIP was obtained from the ZnCr-MMO/FA sample with 0.5 mg FA, which has a reaction rate constant approximately four times greater than that of pure ZnCr-MMO. The improved CIP degradation activity of the ZnCr-MMO/FA composite might not only be due to the good arrangement of ZnCr-MMO particles on the FA surface but also high separation and less recombination of photogenerated electrons-holes pairs, proven by the photoluminescence spectra, photocurrent density, and electrochemical impedance spectroscopy results. The lower recombination of the charge carriers of the ZnCr-MMO/FA composite might be caused by the heterojunction between the ZnCr-MMO as a main photocatalyst and FA. Thus, the proposed ZnCr-MMO/FA composite can be used as an effective photocatalyst for wastewater treatment, including the decomposition of organic pollutants, such as discarded pharmaceuticals.
AB - Visible active photocatalysts have attracted interest as a potentially efficient and sustainable approach for pollutant degradation treatment. In this work, ZnCr mixed metal oxide/fly ash (ZnCr-MMO/FA) composites were prepared using fly ash (FA) from China coal mining power plants to improve photocatalytic performance. The formation of the ZnCr-MMO/FA composites was proved by XRD results which showed the two-phases combination of FA and MMO. Also, the presence of FA in the ZnCr-MMO/FA composite provided a good arrangement of small particles of ZnCr-MMO on the surface of FA and higher light absorption ability with a lower energy bandgap compared with the pure ZnCr-MMO. The photocatalytic performance of the prepared ZnCr-MMO and ZnCr-MMO/FA composites in different FA contents was evaluated by degradation of ciprofloxacin (CIP), which is an antibiotic and often found in pharmaceutical wastes, under visible light irradiation. Clearly, the ZnCr-MMO/FA composites showed higher photocatalytic decomposition of CIP than pristine ZnCr-MMO, and the highest degradation performance for CIP was obtained from the ZnCr-MMO/FA sample with 0.5 mg FA, which has a reaction rate constant approximately four times greater than that of pure ZnCr-MMO. The improved CIP degradation activity of the ZnCr-MMO/FA composite might not only be due to the good arrangement of ZnCr-MMO particles on the FA surface but also high separation and less recombination of photogenerated electrons-holes pairs, proven by the photoluminescence spectra, photocurrent density, and electrochemical impedance spectroscopy results. The lower recombination of the charge carriers of the ZnCr-MMO/FA composite might be caused by the heterojunction between the ZnCr-MMO as a main photocatalyst and FA. Thus, the proposed ZnCr-MMO/FA composite can be used as an effective photocatalyst for wastewater treatment, including the decomposition of organic pollutants, such as discarded pharmaceuticals.
KW - Ciprofloxacin degradation
KW - Fly ash
KW - Photocatalyst
KW - ZnCr mixed metal oxides
UR - http://www.scopus.com/inward/record.url?scp=85123897825&partnerID=8YFLogxK
UR - http://www.scopus.com/inward/citedby.url?scp=85123897825&partnerID=8YFLogxK
U2 - 10.1016/j.jiec.2022.01.006
DO - 10.1016/j.jiec.2022.01.006
M3 - Article
AN - SCOPUS:85123897825
SN - 1226-086X
VL - 108
SP - 263
EP - 273
JO - Journal of Industrial and Engineering Chemistry
JF - Journal of Industrial and Engineering Chemistry
ER -