Photovoltaic Performance of ZnO Nanosheets Solar Cell Sensitized with Beta-Substituted Porphyrin

Arumugam Mahesh

doi:10.1155/2011/301873

Abstract

The photoanode of dye-sensitized solar cell (DSSC) was fabricated using two-dimensional ZnO nanosheets (2D ZnO NSs) sensitized with beta-substituted porphyrins photosensitizer, and its photovoltaic performance in solid-state DSSC with TiO2nanotubes (TiO2TNs) modified poly (ethylene oxide) (PEO) polymer electrolyte was studied. The ZnO NSs were synthesized through hydrothermal method and were characterized through high-resolution scanning electron microscopy (HRSEM), diffused reflectance spectra (DRS), photoluminescence spectra (PL), and X-ray diffraction (XRD) analysis. The crystallinity of the polymer electrolytes was investigated using X-ray diffraction analysis. The photovoltaic performance of the beta-substituted porphyrins sensitized solar cells was evaluated under standard AM1.5G simulated illumination (100 mW cm−2). The efficiency of energy conversion from solar to electrical due to 2D ZnO NSs based DSSCs is 0.13%, which is about 1.6 times higher than that of the control DSSC using ZnO nanoparticles (ZnO NPs) as photoanode (0.08%), when TiO2NTs fillers modified PEO electrolyte was incorporated in the DSSCs. The current-voltage () and photocurrent-time () curves proved stable with effective collection of electrons, when the 2D ZnO nanostructured photoanode was introduced in the solid-state DSSC.

Highlights

Dye-sensitized solar cells (DSSCs) represent a key class of cell architecture that has emerged as a promising candidate for the development of next-generation solar cells
The photoanode fabricated from semiconductor materials need to provide, in addition to a wide band gap and high charge carrier mobility, high surface area for efficient dye sensitization and light harvesting, which can only be achieved by a nanostructured electrode
Insufficient internal surface area of these 1D nanostructure arrays limits the power conversion efficiency at a relatively low level owing to deficient dye loading and light harvesting [12,13,14]. 2D ZnO nanostructures have been studied for DSSCs applications on account of the fact that they have a large specific surface area

Summary

Introduction

Dye-sensitized solar cells (DSSCs) represent a key class of cell architecture that has emerged as a promising candidate for the development of next-generation solar cells. DSSCs with a power conversion efficiency of over 10% have been achieved using a photoanode of TiO2 nanocrystalline films sensitized by ruthenium-based dyes [1,2,3], with suitable engineering and optimization of the nanostructure for its optical, electrical, and morphological properties together with light-harvesting characteristics, and so forth. These cells were shown to deliver relatively high power [4, 5]. Since low-dimensional ZnO nanostructures have exclusive and favorable properties they are considered more suitable for applications in solar energy conversion assemblies

Experimental Details

Results and Discussion

Summary