Abstract

This article reports the molecular structure optimization of novel and biocompatible PVA/Sm@CeO2 polymer nanocomposite with tailored structural, Raman, morphological and optical properties via variation in Samarium (Sm) doping. The composites were prepared by simple mixing technique and characterized by advanced techniques. For optimizing the molecular structure, DFT studies were performed with the Gaussian 16 software using the hybrid density functional B3LYP with the D2 version of Grimme’s dispersion (B3LYP-GD2). Reduction in crystallite size (9.49 to 8.21 nm) and micro-strain (4.48 × 10?3 to 3.81 × 10?3) in the nanocomposites due to Sm-doping were confirmed by X-ray diffraction technique. The shift in optical parameters i.e. absorption edge, optical bandgap, refractive index and Urbach energy due to Sm-doping in the composites were also confirmed by UV-Vis-NIR photo-spectrometer. The variation in these optical parameters was not found to be steady with increasing doping amount which confirmed that the modulation in the optical parameters arises from a balance between defect passivation at low Sm doping and defect creation along with the distortion at higher Sm doping levels. The shift in emission peaks of photoluminescence spectra due to Sm doping has also been confirmed via studying the CIE coordinates. In FTIR spectra, prominent bands at 2921.84 cm?1, 3254.87 cm?1 and 3717.03 cm?1 are due to C–H and O–H stretching vibrations. The bands at 1700 cm?1, 1527 cm?1, and 1245 cm?1 arise due to carbon oxygen stretching vibration of double bonded carbon–oxygen C = O, C = C, C-O, respectively. This study confirms successful incorporation of nanofillers in the composite. DFT results confirm that the prepared PVA/Sm@CeO2 nanocomposites are quite stable thermodynamically and capable of interaction potentially with polar compounds in the environment, which might lead to it for tunable optoelectronics application. © 2025 Informa UK Limited, trading as Taylor & Francis Group.