Photoluminescence of uniformly distributed ZnSe nanoparticles in PVA polymer matrix
Department of Applied Physics, Jabalpur Engineering College, Jabalpur, M. P., 482001, India.
Abstract: The Luminescence properties of ZnSe/PVA were investigated with different Zn2+ and with different PVA concentrations. These nanocomposite samples were prepared by environmental friendly chemical method. The prepared samples were characterized by using X-Ray Diffraction (XRD), Atomic force microscope (AFM) and photoluminescence (PL). The X ray diffraction revealed cubic structure of ZnSe/PVA with particle size less than 20 nm. ZnSe/PVA samples with varying Zn2+ content were excited by UV light of 230 nm and shown in figure. This PL spectrum of MSe/PVA revealed that, PL peak is found to shift towards shorter wavelength by increasing metal ion M2+ content i.e. Zn2+ .
The emission may be attributed to transition from various surface states of ZnSe nano. The oscillator strength is increased by reducing the size which enhances the PL intensity. The blue shift could be attributed to size reduction of ZnSe nanoparticles in PVA matrix. Due to proper passivation of surface states non-radiative transition are reduced which enhances the PL intensity. The polymer matrix acts to stabilize the nano particle. Due to the PL peak in blue region these composite films are promising materials for optical display devices.AFM observations revealed uniform distribution of MSe nanoparticles particle in PVA matrix with nanometer regime, showed strong agreement with those obtained from XRD.
Keywords: ZnSe/PVA Nanocomposite; XRD; AFM; Photoluminescence