Charge transport in eosin yellow sensitized CdS 1-D nanostructures is studied. Direct conduction pathway for electron transport in nanowires enhances in CdS nanowires compared to nanorods and nanoparticles. characterization of nanowires results in improved efficiency of 0.184% due to fewer interparticle connections. Increase in is observed by coating CdS 1-D nanostructures on TiO2 substrate which reduces rate of recombination and photocorrosive nature of CdS photoanodes. Enhancement in efficiency up to 0.501% is achieved for CdS 1-D nanostructures DSSCs on TiO2 substrate. 1. Introduction Dye sensitized solar cells (DSSCs) offer the hope of fabricating photovoltaic devices with high efficiency at low cost by simple fabricating process, as an alternative to conventional p-n junction photovoltaic device [1]. Recently, cadmium sulphide (CdS) is reported to be an active promising alternative material due to its direct band gap (2.3？eV), corresponding to the spectrum of visible light [2]. In DSSC, the dye adsorbed photoanodic film plays an important role because it serves as a pathway for photoinjected electrons. The overall cell performance strongly depends on the surface and electronic properties of photo anodes [3]. Electron transport in nanoparticles (NPs) based DSSCs occurs by a series of hopping events between trap states on neighboring particles [3, 4], whereas in 1-D nanostructures such as nanorods (NRs), nanowires (NWs) direct conduction pathway of electron transport from the point of generation to the collection electrode maintains high surface area for dye adsorption [5]. Two- to three-fold increase in photo conversion efficiency of CdS nanowires (NWs) (0.18%) is observed than CdS nanorods (NRs) (0.08%) and CdS nanoparticles (NPs) (0.06%). Yang et al. [6] reported that 1-D nanostructure including NWs and NRs facilitates photon absorption and electron transport with improved efficiencies. Reda and El-Sherbieny [2] reported fluorescein sensitized CdS NP photoanodes with efficiency of 0.022% and concluded that the anchoring amino acid groups (basic dyes) present in the CdS surface resist the electron transfer from the excited state to the conduction band of CdS which suppressed the photoelectric conversion. The significant factor to be considered in improving overall solar cell efficiency is the separation of the generated electron-hole pairs. Although exciton generation can be enhanced by using nanoparticles and charge transport by using nanowires, efficient charge separation can be achieved by exploiting a heterojunction between two different
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