Functionalized multi-walled carbon nanotubes for enhanced photocurrent in dye-sensitized solar cells

Abstract

The influence of the incorporation of nitric acid-treated (functionalized) multi-walled carbon nanotubes (f-MWCNTs) and unmodified MWCNTs in TiO2 films are investigated by observing the photocurrent-voltage characteristics of dye-sensitized solar cells (DSSCs) with and without MWCNTs. The short-circuit photocurrent (Jsc) of the modified DSSC increased by 46% compared with that of a cell with plain TiO2 film. The open-circuit voltage remained the same for all cases. The enhanced Jsc is explained by the increased surface area of the film, enhanced cluster formation of TiO2 particles around f-MWCNTs, and improved interconnectivity of TiO2 particles in the presence of f-MWCNTs. The efficiency of the cell increased by 45% due to Jsc enhancement.