Jump to Main Content
Facile synthesis of carbon nanotubes covalently modified with ZnO nanorods for enhanced photodecomposition of dyes
- Tie, Weiwei, Zheng, Zhao, Xu, Chao, Zheng, Zhi, Bhattacharyya, Surjya Sarathi, He, Weiwei, Lee, Seung Hee
- Journal of colloid and interface science 2019 v.537 pp. 652-660
- Raman spectroscopy, X-ray photoelectron spectroscopy, absorption, carbon nanotubes, chemical bonding, dyes, electric current, electron paramagnetic resonance spectroscopy, ions, microstructure, nanohybrids, nanorods, photocatalysis, photolysis, rhodamines, scanning electron microscopy, superoxide anion, zinc, zinc oxide
- Utilizing a one-pot solvothermal procedure novel one-dimensional zinc oxide–carbon nanotube nanohybrids (ZnCT) were synthesized in alcohol-alkali solution, free of catalytic assistance. The ZnCT hybrids were prepared through covalent modification of zinc oxide nanorods (ZnO NRs) with functionalized carbon nanotubes (f-CNTs). The morphology and microstructure of as-prepared ZnCT hybrids were characterized by scanning electron microscopy (SEM), powder X-ray diffraction, Raman, X-ray photoelectron and UV–vis absorption spectroscopies. SEM images of the ZnCT hybrids indicated that the ZnOethanol NRs grew longer along the vertical radial (0 0 0 1) surface and aggregated to a lesser extent than the analogous ZnOmethanol NRs. Photodegradation analysis showed that the off-white ZnCTethanol hybrid with ascendant UV–visible light absorption had displayed superior photocatalytic activity towards Rhodamine B (RhB) dyes than either pure ZnOethanol, ZnOmethanol NRs or ZnCTmethanol hybrid, among which the photocatalytic activity of ZnOethanol NRs was better than that of ZnOmethanol NRs. Raman and X-ray photoelectron spectroscopy analyses confirmed a strong interaction between f-CNTs and ZnOethanol NRs in ZnCTethanol hybrid, in which Zn ions were chemically bonded to negatively charged oxygen-containing groups at the graphene-like surface of f-CNTs. The enhanced separation lifetime of the photogenerated electron-hole observed by surface photovoltage and photocurrent measurements of the ZnCTethanol hybrid was attributed to the efficient covalent linking of ZnOC and close contact configuration between the f-CNTs and ZnOethanol NRs. Further controlled photodegradation and electron spin resonance (ESR) analyses revealed that the photodegradation of RhB dyes resulted from photogenerated holes, and radical species, such as O2−, OH−, which were formed in-situ. Details of the photocatalytic mechanism were also explored herein.