TY - JOUR
T1 - Effect of transformation temperature toward optical properties of derived CuO/ZnO composite from Cu–Zn hydroxide nitrate for photocatalytic ciprofloxacin degradation
AU - Trakulmututa, Jirawat
AU - Chuaicham, Chitiphon
AU - Shenoy, Sulakshana
AU - Srikhaow, Assadawoot
AU - Sasaki, Keiko
AU - Smith, Siwaporn Meejoo
N1 - Funding Information:
This work was financially supported by Mahidol University (Basic Research Fund: fiscal year 2022; Grant no. BRF1-046/2565 ) and was supported by the Japan Society for the Promotion of Science (JSPS) KAKENHI (A) [No. JSPS JP22H00266 ] to KS and providing postdoctoral fellowship for foreign researchers ( JP21P21342 and JP22P22083 ). This work was supported by 2022 Research Start Program 202208. JT received a PhD scholarship from Science Achievement Scholarship of Thailand (SAST) and postgraduate student mobility 2022 by Mahidol University for his research visit in Japan.
Funding Information:
Under light irradiation, photogenerated electron-hole pairs were produced on the surface of photocatalysts to further carry out degradation or organic compounds. Undesirable recombination of the charge carriers, if occurred, resulted in ineffective photocatalytic degradation reactions. To elucidate the recombination of e−-h+ in each material, PL spectra were recorded and shown in Fig. 7. The materials giving low PL intensity are expected to be effective photocatalyst, due to the effective suppressed e−-h+ recombination processes [48]. The PL profile of 400HN sample after light excitation at 300 nm displayed the lowest intensity at the emission wavelength at 442 nm, corresponding to the highest photocatalytic performance for 400HN compared to that obtained from other samples. The possible reason of minimized PL intensity is the formation of p-n heterojunction between p-type CuO and n-type ZnO inhibited the photogenerated e−-h+ recombination [25]. Furthermore, the increase of PL intensity in 800HN sample may be caused from the enhancement of crystallinity (Fig. 1b), being supported by a previous report [44].This work was financially supported by Mahidol University (Basic Research Fund: fiscal year 2022; Grant no. BRF1-046/2565) and was supported by the Japan Society for the Promotion of Science (JSPS) KAKENHI (A) [No. JSPS JP22H00266] to KS and providing postdoctoral fellowship for foreign researchers (JP21P21342 and JP22P22083). This work was supported by 2022 Research Start Program 202208. JT received a PhD scholarship from Science Achievement Scholarship of Thailand (SAST) and postgraduate student mobility 2022 by Mahidol University for his research visit in Japan.The authors would like to thank the Nanotech Center, Kyushu University for the XPS measurements and also Department of Chemistry, Faculty of Science, Mahidol University for TGA instrument. This work was partly supported by Mahidol University (Basic Research Fund: fiscal year 2022; Grant no. BRF1-046/2565), and Advanced Research Infrastructure for Materials and Nanotechnology Grant Number JPMXP1222KU1009 in Japan sponsored by the Ministry of Education, Culture, Sports, Science and Technology (MEXT), Japan.
Publisher Copyright:
© 2022 Elsevier B.V.
PY - 2022/11
Y1 - 2022/11
N2 - In this work, visible light driven CuO/ZnO photocatalyst composite derived from Cu–Zn hydroxide nitrate (CuZn–HN) was fabricated via thermal transformation at varying temperatures. The effect of temperature on their morphology and optical properties was examined. The CuZn–HN calcined at 400 °C (400HN) showed the better performance than 200HN, 800HN and uncalcined CuZn–HN in terms of the photocatalytic oxidation rate for Ciprofloxacin (CIP) degradation under visible light irradiation conditions. The improved photocatalytic performance of 400HN could resulted from the combination of narrow energy band gap, suppressed photogenerated e−-h+ recombination, and strong interactions between CIP and the composite' surface. The finding suggested the transformation temperature of CuZn–HN to CuO/ZnO composite is a key factor to produce the highly effective photocatalyst with the simple protocol as an alternative synthetic method to prepare the mixed metal oxide composites. Moreover, the photocatalytic CIP degradation pathway was elucidated by GC-MS analysis, and the charge transfer mechanism in CuO/ZnO composite was also proposed.
AB - In this work, visible light driven CuO/ZnO photocatalyst composite derived from Cu–Zn hydroxide nitrate (CuZn–HN) was fabricated via thermal transformation at varying temperatures. The effect of temperature on their morphology and optical properties was examined. The CuZn–HN calcined at 400 °C (400HN) showed the better performance than 200HN, 800HN and uncalcined CuZn–HN in terms of the photocatalytic oxidation rate for Ciprofloxacin (CIP) degradation under visible light irradiation conditions. The improved photocatalytic performance of 400HN could resulted from the combination of narrow energy band gap, suppressed photogenerated e−-h+ recombination, and strong interactions between CIP and the composite' surface. The finding suggested the transformation temperature of CuZn–HN to CuO/ZnO composite is a key factor to produce the highly effective photocatalyst with the simple protocol as an alternative synthetic method to prepare the mixed metal oxide composites. Moreover, the photocatalytic CIP degradation pathway was elucidated by GC-MS analysis, and the charge transfer mechanism in CuO/ZnO composite was also proposed.
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U2 - 10.1016/j.optmat.2022.112941
DO - 10.1016/j.optmat.2022.112941
M3 - Article
AN - SCOPUS:85137827892
VL - 133
JO - Optical Materials
JF - Optical Materials
SN - 0925-3467
M1 - 112941
ER -