Experimental investigation on the structural, dielectric, ferroelectric and piezoelectric properties of La doped ZnO nanoparticles and their application in dye-sensitized solar cells

• Published in: Physica. E, Low-dimensional systems & nanostructures Low-dimensional systems & nanostructures, 2017-07, Vol.91, p.72-81
• Main Authors: Goel, Sahil, Sinha, Nidhi, Yadav, Harsh, Joseph, Abhilash J., Kumar, Binay
• Format: Article
• Language: English
• Subjects: Dye-sensitized solar cells; Ferrolectricity; Nanorods; Piezoelectricity; Transmission electron microscopy; ZnO
• ISSN: 1386-9477; 1873-1759
• DOI: 10.1016/j.physe.2017.04.010

Pure and lanthanum (La) doped ZnO nanorods were synthesized via co-precipitation method. The structure and morphology of as grown ZnO and La-ZnO nanoparticles were studied using transmission electron microscopy (TEM) and powder X-ray diffraction (XRD) methods. The values of remnant polarization and coercive field were found to be 0.027μC/cm2 and 1.33kV/cm, respectively, for as grown La-ZnO nanostructures. High Curie temperature (276°C) for doped ZnO was observed in dielectric study. Piezoelectric coefficient at room temperature was found to be 101.30pm/V. I-V characteristics were studied for both pure and doped ZnO nanoparticles. Photo-anodes of dye-sensitized solar cells (DSSCs) were made using ZnO and La-ZnO nanorods. The conversion efficiency and short circuit current density of La-ZnO nanorods based DSSC were 0.36% and 1.31mA/cm2, respectively, which were found to be largely enhanced when compared with that of pure ZnO based DSSC (0.20% and 0.94mA/cm2). [Display omitted] •Pure and La-doped ZnO nanorods were grown by wet chemical route.•High ferroelectric phase transition for La-ZnO was observed at 276°C.•Large d33 (101.30pm/V) for La-ZnO was calculated from the butterfly loop.•Two DSSCs were fabricated using pure ZnO and La-ZnO.•DSSC efficiency increased from 0.20% to 0.36% as a result of La dopant.