Study on CaCO₃-coated ZnO nanoparticles based dye sensitized solar cell

Dye sensitized solar cells (DSSCs) have been fabricated using ZnO and CaCO₃-coated ZnO nanoparticles. The effect of CaCO₃ coating on the performance of DSSC has been investigated. CaCO₃-coated ZnO nanoparticles have been synthesized by hydrothermal method. X-ray diffraction patterns of synthesized nanoparticles reveal that the ZnO and CaCO₃-coated ZnO nanoparticles have respectively wurtzite and rhomb-centred structure and both having hexagonal phase. Transmission electron microscopy study reveal that ZnO and CaCO₃-coated ZnO nanoparticles possess spherical symmetry and have average particle size respectively 6.2 and 6.7 nm. In case of CaCO₃/ZnO nanoparticles, the quenching in photoluminescence emission intensity has been attributed to the decrease in recombination rate of photo-generated electron–hole pairs. UV–Vis absorption spectra, confirms that the electrodes fabricated from the CaCO₃-coated ZnO nanoparticles have higher absorbance that shows their higher dye adsorbing power. The use of CaCO₃ coating has been found to enhance the efficiency of DSSC by over 100 %.