Interfacial Engineering in Functional Materials for Dye-Sensitized Solar Cells

11 Graphene‐Based Nanocomposite as Photoanode

Subhendu K. Panda G. Murugadoss and R. Thangamuthu

CSIR – Central Electrochemical Research Institute, Karaikudi, India

11.1 Introduction

There are several ways of modifying dye‐sensitized solar cell (DSSC) in order to improve the power conversion efficiency (PCE). Photoanode modification is one of the important methods in addition to alteration in the counterelectrode. Since the photoanode in DSSC acts as a light harvester as well as a charge carrier, the modification of the photoanode hence plays a crucial role in enhancing the PCE of the cell. Photoanode is the backbone of DSSC that is why its material, shape, and size have to be carefully selected and optimized for the better performance of the cell. For an ideal photoanode, following should be the key features: (i) high surface area for improving dye loading, (ii) fast electron transfer, (iii) high resistance to photo‐corrosion, (iv) good transparency, and (v) it should have ability to absorb/scatter the sun light. In general, mesoporous TiO₂ has been widely used most effective metal oxide for photoanode in DSSCs due to its low cost, high stability, abundant in nature, attractive optical and electronic properties, and environment friendliness. The most efficient solar cell developed with TiO₂ delivered approximately 12–14% photo‐conversion efficiency [1,2]. Various other metal oxides such as ZnO [3], SnO₂ [4], Nb₂O₅ [5], SrTiO₃ [6], Zn₂SnO₄ [7], and WO₃ [8] have ...