Green synthesis of ionic liquid assisted ytterbium oxide nanoparticles by Couroupita guianensis abul leaves extract for biological applications

Rare earth element ytterbium oxide (Yb2O3) and ionic liquid (IL) added ytterbium oxide (Yb2O3-IL) nanoparticles (NPs) were synthesized using Couroupita guianensis abul leaves extract by hydrothermal method. The synthesized Yb2O3 and Yb2O3-IL NPs are of BCC structure and crystalline size of 40 and 35 nm. Functional group and vibrational mode were analyzed by FTIR and Raman spectroscopy and the resultant Yb-O stretching peak at 618 and 588 cm(-1). The optical absorption at 239 and 230 nm for Yb2O3 and Yb2O3-IL NPs were studied by UV-vis spectroscopy. The relative high-intensity emission peaks at 424 (blue) and 583 (yellow) were confirmed by photoluminescence spectroscopy. The particle size of Yb2O3-IL observed in the range of around 15-37 nm was confirmed by DLS method and the results matched with SEM analysis. The Yb, O 1s and C 1s states and the corresponding binding energy (BE) values were confirmed by X-ray photoelectron spectroscopy. The hexagonal, spherical and rectangular shapes were identified by SEM and TEM analyses. Biological activities such as anti-bacterial against E. coli and S. aureus, anti-cancer against MCF-7 breast cancer cells, anti-inflammatory against bovine serum albumin denaturation with standard diclofenac and anti-oxidant against free radical scavenging assay with Vitamin C were also studied for the synthesized Yb2O3 and Yb2O3-IL NPs.