Synthesis of CNT based nanocomposites and their application as photoanode material for improved efficiency in DSSC

Carbon nanotube (CNT) based binary and ternary nanocomposites synthesized through a simple precipitation method and their application in Dye Sensitized Solar Cell (DSSC) are reported in this work. The synthesized nanocomposites are characterized using X-Ray Diffraction (XRD), High Resolution Transmission Electron Microscopy (HRTEM), Scanning Electron Microscopy (SEM), UV-visible absorption spectroscopy, Photoluminescence (PL) and Fourier Transform Infra-Red Spectroscopy (FTIR). The morphological characterizations reveal that ZnO/CuO/CNT nanocomposites are more agglomerated than ZnO/CNT. ZnO/CNT based DSSC shows better photoconversion efficiency than ZnO/CuO/CNT. ZnO/CuO/CNT nanocomposites provide improved surface area by forming better heterojunctions of ZnO and CuO but increased agglomeration of the particles which results in reduction of photoconversion efficiency compared to ZnO/CNT based DSSC. It is found that the proportion of CNTs used for nanocomposite preparation is another important factor to be considered for photovoltaic applications. Comparison with already reported results of ZnO/CNT preparation procedures reveals that precipitation using a green reagent is a novel approach with comparable results to that of direct blending method. Moreover, the Jsc and fill factor is highly improved as compared to the ZnO/CNT prepared by hydrothermal procedures. Optimization of the CNT loading can further enhance the Jsc, Voc and efficiency of ZnO/CNT nanocomposite based DSSC.