Green synthesis of Ag and the effect of Ag on the efficiency of TiO_2 based dye sensitized solar cell

摘要

Green synthesis of silver nanoparticles (AgNPs) was carried out using the aqueous extract of Carcia papaya (commonly known as papaya) leaves as reducing and capping agent. The synthesized AgNPs colloid was mixed with titanium dioxide slurry to produce Ag:TiO_2 nanocomposite. The as-synthesized AgNPs and Ag:TiO_2 nanocomposite were characterized for structural, optical and morphological studies. Dye sensitized solar cells (DSSCs) were fabricated with pure TiO_2 and Ag:TiO_2 nanocomposite photoanodes using N719 dye and their performance was investigated. The power conversion efficiency of Ag:TiO_2 nanocomposite DSSC is increased by about 33.5% when compared to the efficiency of the pure TiO_2 DSSC. The electrochemical impedance spectroscopic measurements showed that Ag:TiO_2 nanocomposite film effectively reduce the charge transfer resistance and also increased the lifetime of the electron.