Synthesis and Characterisation of Cyclodextrin/ Sudan Black-B Caped ZnO/ Nanocrystals
Palanichamy Ramasamy, A. Mani, Balakrishnan Sneha, Ezhil Nivetha, Albert Prabhu, G. Venkatesh, P. Senthilraja, Narayanasamy Rajendiran
Abstract
Sudan black-B/cyclodextrin/zinc oxide (SBB/CD/ZnO) nanoparticles are prepared and characterized by various spectral and microscopic methods. Nanoparticle size was measured by TEM-EDS and X-RD methods. The effect of different polarities of the solvents, α-cyclodextrin (α-CD) and β-cyclodextrin (β-CD), on SBB was studied by various spectral methods. The inclusion behavior of SBB on both CDs was determined by the PM3 method. The doping effect of SBB/CD on ZnO nano was investigated by UV-visible, fluorescence, FTIR, DTA, XRD, FE-SEM, and TEM methods. The azo SBB dye has been included within the cyclodextrin cavities to form a noncovalent SBB/CD assembly in aqueous solution. The presence of an isosbestic point suggests that a 1:1 inclusion complex is formed. The HOMO-LUMO gap for the SBB/β-CD inclusion complex was more negative, which supports that this complex is more stable than SBB/α-CD inclusion complex. The SBB/CD capped ZnO nanocrystals absorb strongly in the visible region (425-650 nm) and emit at 520 nm. SBB absorption noted at 587 nm is moved to 650 nm in SBB/CD/ZnO, indicating efficient resonance energy transfer (RET) from the ZnO nano to the included SBB dye. FTIR, XRD, and TGA peaks of SBB/CD are different from ZnO/SBB/CD. SEM and TEM images showed nanocrystals are formed in ZnO/SBB/β-CD.