Evaluation of structure, morphology and dye degradation performance of zinc oxide doped with ionic liquid

Full text: The industrial development and population growth cause serious damage to the environment, especially the aquatic pollution. Among the main pollutants of water, organics dyes stand out. Many methods have been developed to eliminate organic dyes from the water, highlighting the photocatalytic degradation [1]. ZnO is considered promising as photocatalyst for organic dye degradation due many characteristics as low cost and environmental sustainability. However, this oxide have low photocatalytic performance, which makes it impossible to apply them a commercial photocatalyst. One solution to improve your efficiency is to modify the ZnO structure by controlling the material's morphology. In this work, ZnO particles synthetized by the microwave assisted hydrothermal method were modified by incorporation of two ionic liquids (1-methyl-3-butylimidazolium chloride and 1-hexadecyl-3-methylimidazolium chloride). Modified and unmodified ZnO particles were characterized by XRD analyses, Field Emission Gun-Scanning Electron Microscopy (FEG-SEM) micrographs, Ultraviolet-visible (UV–vis) absorption spectra, Photo luminescence (PL) measurements and by photodegradation of Rhodamine B (RhB). The addition of IL in the particles does not change the structure. However, it reduces the particle size and changed shallow defects to deep defects. These changes in the particles shows that the degradation of the dye reaches 63% for ZnO/C1645 whereas for pure ZnO it reaches 30% in the same time interval. The results indicate that the ZnO/ C1645 composite is promising to be used as photocatalyst for organic dye degradation. References: [1] S. Cao, J. Low, J. Yu, M. Jaroniec, Adv. Mater. 27 (13) (2015) 2150-2176. (author)