Archive – 2013

Heterovalent cation substitutional doping for quantum dot homojunction solar cells

We report in a recent article in Nature Communication a novel doping scheme for colloidal quantum dots that enables the development of colloidal quantum dot homojunction solar c20131218_konstantatosells. Doping in colloidal quantum dots has remained a grand challenge for many years. Recent efforts have demonstrated the effect of doping in the optical properties of quantum dots, however robust electronic-active doping has remained elusive.

In this work, we demonstrated that the doping character of colloidal quantum dots can be controlled by introducing heterovalent dopant cation atoms to transform a p-type semiconductor into an n-type semiconductor. We have then shown that this can be utilized in robust solar cell structures operating under ambient conditions with respectable efficiencies.

Reference: Alexandros Stavrinadis, Arup K. Rath, F. Pelayo García de Arquer, Silke L. Diedenhofen, César Magén, Luis Martinez, David So, Gerasimos Konstantatos
Heterovalent cation substitutional doping for quantum dot homojunction solar cells
Nature Communications, doi: 10.1038/ncomms3981

High-Efficiency Solar Cells9783319019871

The book High-Efficiency Solar Cells – Physics, Materials, and Devices,Series: Springer Series in Materials Science, Vol. 190 by Wang, Xiaodong; Wang, Zhiming M. (Eds.) has been recently published and includes our chapter Broadband and Omnidirectional Anti-reflection Coating for III/V Multi-junction Solar Cells.

I have presented my recent findings at the 1st EOS Topical Meeting on Optics at the Nanoscale in Capri, Italy.

Solution-processed hybrid organic-inorganic bulk heterojunction solar cells

Figure_TOCIn collaboration with researchers from the Department of Applied Chemistry at University of Tokyo, we demonstrated solution-processed hybrid organic-inorganic bulk heterojunction devices employing P3HT in conjunction with bismuth sulfide nanocrystals as the electron accepting material. These devices attain power conversion efficiencies of 1% extending at the same time the sensitivity of P3HT into near-infrared wavelengths. The reported infrared sensitization levels of 30% are among the highest ever reported with P3HT.

 

Reference: L. Martinez, A. Stavrinadis, S. Higuchi, S. L. Diedenhofen, M. Bernechea, K. Tajima, G. Konstantatos
Hybrid solution-processed bulk heterojunction solar cells based on bismuth sulfide nanocrystals
Phys. Chem. Chem. Phys. 15, 5482-5487 (2013)