Enhanced photoconversion efficiency in dye-sensitized solar cells through Ag and La modified ZnO photoanodes

Abstract This work synthesized ZnO nanoparticles doped and co-doped with Ag and La using a cost-efficient sol–gel method. The structural and morphological features of the nanoparticles were characterized by x-ray diffraction (XRD) and field emission scanning electron microscopy (FESEM). The XRD and FE-SEM confirm the formation of the hexagonal structure of all the synthesized samples. Optical properties were analyzed using UV–visible absorption and photoluminescence spectroscopy. These nanoparticles were subsequently employed as photoanodes in dye-sensitized solar cells (DSSCs). Several configurations of Ag and La doped and co-doped ZnO nanoparticles were tested as photoanodes to assess their impact on device performance. The introduction of Ag and La dopants into ZnO leads to a notable enhancement in the photovoltaic efficiency of the DSSCs. The DSSC incorporating bare ZnO photoanode achieved an efficiency of 0.2554% and on the other hand Ag and La co-doped ZnO photoanode achieved the highest efficiency of 0.9483%, a 271% increase compared to DSSC using undoped ZnO photoanodes. This significant improvement is attributed to the combined effects of Ag and La ions. Ag ions help create a blocking layer that suppresses electron recombination, while La ions enhance light absorption by broadening the spectrum through up/down conversion. The combined effect of Ag and La dopants is responsible for the observed efficiency enhancement in the DSSCs.