Hybrid Perovskite/Polymer Materials: Preparation and Physicochemical Properties

The aim of this work is to investigate the preparation, the optical properties, and the stability over time of a colloidal organic–inorganic hybrid perovskite (CH3NH3PbBr3)/random copolymer P(MMA-co- DMAEMA) system. Different ratios of perovskite to copolymer were used to study its effect on stability and properties. The optical properties were investigated by UV-Vis and fluorescence spectroscopy. Dynamic light scattering was used to determine the size, and the size polydispersity of the colloidal hybrid particles; while morphology was investigated by transmission electron microscopy. Photoluminescence decay studies revealed the interaction of the random copolymer with the perovskite. Finally, thin-films were prepared, to investigate the optical properties of the samples in the absence of the solvent. High temporal stability of the optical properties of thin hybrid films was observed under certain conditions.

Engineering defect clusters in distorted NaMgF3 perovskite and their important roles in tuning the emission characteristics of Eu3+ dopant ion

Defect engineering in distorted NaMgF3 can be achieved by doping different amounts of dopant (Eu3+) and co-dopant (Li+) ions, which has a significant impact on the emission spectrum and photoluminescence decay profile of the Eu3+ ion.

Tuning the Photo-Luminescence Properties of WO3 Layers by the Adjustment of Layer Formation Conditions

In this research we have applied sol-gel synthesis for the deposition of tungsten (VI) oxide (WO3) layers using two different reductants (ethanol and propanol) and applying different dipping times. WO3 samples were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), Fourier Transform Infrared spectroscopy (FTIR), photoluminescence (PL) and time-resolved photoluminescence decay methods. Photoelectrochemical (PEC) behaviour of synthesized coatings was investigated using cyclic voltammetry in the dark and under illumination. Formation of different structures in differently prepared samples was revealed and significant differences in the PL spectra and PEC performance of the samples were observed. The results showed that reductant used in the synthesis and dipping time strongly influenced photo-electrochemical properties of the coatings. Correlation between the morphology, PL and PEC behaviour has been explained.