High-performance dye-sensitized solar cells with various nanostructured materials as counter electrode

Abstract

This paper reports high-performance dye-sensitized solar cells (DSCs) with two classes of nanostructured materials as counter electrode. The first one is nanostructured platinum (Pt) prepared by chemically reducing a Pt precursor with ethylene glycol (EG) at temperature below 200 d̀C. Two types of Pt structures, dense and porous Pt structures, were observed for the Pt deposited by EG reduction. The dense Pt structure is the result of Pt growth from the substrate immediately after the reduction, whereas the porous Pt structure originates from the precipitation of Pt nanoparticles. Pt deposited by this method could be used as the counter electrode of high-performance DSCs. The DSCs exhibited a power conversion efficiency (PCE) of 8.1%, quite close to that of the DSCs with Pt counter electrode prepared by the conventional pyrolysis. In addition, this low-temperature method enabled the Pt deposition on flexible substrate, which could be used as the flexible counter electrode for DSCs. The second types of materials are naoncomposites of multi-walled carbon nanotubes (MWCNTs) and poly(3, 4-ethy lenedioxy thiophene): poly (styrenesulfonate) (PEDOT:PSS) that is a conducting polymer. The composite films were prepared by spin-coating aqueous solutions of MWCNT/PEDOT: PSS composites. The devices exhibited a PCE of 6.5%.