Investigation the influence of Zn2+ doping on the photovoltaic properties (DSSCs) of MgO nanoparticles

The present work demonstrates the synthesis of MgO and ZnO-MgO nanospheres with various con- centration (2, 4, 6, 8 and 10 wt%) of Zn2+ through microwave combustion route using magnesium nitrate and zinc nitrate as precursors and ethylene glycol as solvent. The effect of doping was studied through powder X-ray diffraction (XRD), scanning electron microscopy (SEM), energy-dispersive analysis using X- rays (EDAX), transmission electron microscopy (TEM) and photoconductivity (I-V) technique. Tryptan Blue, SPADNS and Evans Blue dyes were used for the first time as a photosensitizer on ZnO-MgO nanoparticles. Optical and electrochemical characteristics of dyes revealed that the optical bandgap, HOMO and LUMO levels of dyes are well matched with conduction band of ZnO-MgO nanoparticles. I-V characteristics of ZnO-MgO films before and after sensitisation with dyes revealed the influence of dye sensitisation on photo conductivity of ZnO-MgO nanoparticles. In addition, the better adsorption of Trypan Blue (TB), SPADNS (SPD) and Evans Blue (EB) dyes on ZnO-MgO film is due to porous nature of ZnO-MgO. This gives more transportation of electron from dye to ZnO-MgO which enhances the power conversion efficiency of solar cell. (C) 2020 Elsevier B.V. All rights reserved.