Publication Type:Journal Article
Source:Nano LettNano Lett, Volume 13, Number 1, p.95-9 (2013)
ISBN:1530-6992 (Electronic)<br/>1530-6984 (Linking)
<p>Carrier transport characteristics in high-efficiency single-walled carbon nanotubes (SWNTs)/silicon (Si) hybrid solar cells are presented. The solar cells were fabricated by depositing intrinsic p-type SWNT thin-films on n-type Si wafers without involving any high-temperature process for p-n junction formation. The optimized cells showed a device ideality factor close to unity and a record-high power-conversion-efficiency of >11%. By investigating the dark forward current density characteristics with varying temperature, we have identified that the temperature-dependent current rectification originates from the thermally activated band-to-band transition of carriers in Si, and the role of the SWNT thin films is to establish a built-in potential for carrier separation/collection. We have also established that the dominant carrier transport mechanism is diffusion, with minimal interface recombination. This is further supported by the observation of a long minority carrier lifetime of ~34 mus, determined by the transient recovery method. This study suggests that these hybrid solar cells operate in the same manner as single crystalline p-n homojunction Si solar cells.</p>
Jung, Yeonwoong<br/>Li, Xiaokai<br/>Rajan, Nitin K<br/>Taylor, Andre D<br/>Reed, Mark A<br/>eng<br/>2012/12/15 06:00<br/>Nano Lett. 2013 Jan 9;13(1):95-9. doi: 10.1021/nl3035652. Epub 2012 Dec 17.