Search for content and authors

First solar cells based on CdTe nanoparticles/MEH-PPV composites

Sandeep Kumar ,  Thomas Nann 

Materials forschungcentrum (FMF), Stephen Meier str. 21, Freiburg 79104, Germany


Market expansion in the use of conventional inorganic solar cells remains limited due to high costs imposed by fabrication procedures involving elevated temperatures, high vacuum and numerous lithographic steps and discrete processing due to glass carriers.
Organic solar cells having one of the components as conducting polymers can serve as a cost effective alternative to conventional inorganic solar cells because of the processing advantages of polymers. These polymers can be solution processed and their good mechanical properties opens the possibility to design it in flexible shape and sizes. Solar cells based on CdSe nanoparticles and conducting polymers were realised and a maximum efficiency of 1.7% was obtained. The performance of such a solar cell can be improved further by extending partly the nanoparticle absorption in the IR region by using CdTe nanoparticles. The onset of absorption of of CdSe in bulk is 720 nm while that of CdTe is 820 nm. This shift of 100 nm in wavelength for CdTe can improve the absorption of of sunlight by 20% relative to CdSe. Furthermore the electron mobility of CdTe is higher compared to CdSe and hence can be looked as a better material to be used in polymer solar cells.
In this report we present for the first time a solar cell based on CdTe nanopartricle/ MEH- PPV composites. Being a new system a systematic approach was carried out from synthesising nanoparticles to building solar cells. A new organometallic route was developed for synthesis of CdTe nanorods. Cyclic voltammetry measurements were carried to determine the HOMO and LUMO levels of the nanoparticles and MEH-PPV to see if they meet the proper energy level alignment for a possible charge transfer. Evidence for charge transfer was further confirmed by PL quenching. Once the evidence for charge transfer was confirmed solar cells were build using spin coating on ITO substrate and an efficiency of 0.05% was obtained for first cells under AM 1.5 conditions.


Legal notice
  • Legal notice:

Related papers

Presentation: oral at E-MRS Fall Meeting 2004, Symposium A, by Sandeep Kumar
See On-line Journal of E-MRS Fall Meeting 2004

Submitted: 2004-04-01 15:37
Revised:   2009-06-08 12:55