Precision printing and optical modeling of ultrathin SWCNT/C60 heterojunction solar cells
Inexpensive photovoltaics (PV) are an attractive avenue of research in the field of solar cells. In particular, semi-conducting single-walled carbon nanotubes (s-SWCNTs) are a promising photo-absorbing material due to their strong near-infrared (near-IR) absorption and high carrier mobility. However, most current production methods for SWCNT PVs suffer from high surface roughness and lack nanometer-scale deposition precision, thereby hampering the reproducibility of ultrathin PV devices.
To this end, the authors have utilized ultrasonic spraying in order to tune the thickness of s-SWCNT layers with nanometer-scale precision. The researchers have used a combination of atomic force microscopy (AFM) and optical profilometry to show that their ultrasonic spraying method produces smooth, uniform films with an average roughness of about 5 nm. The advantage of this low roughness enables fabrication of s-SWCT/C60 bilayer devices with significantly thinner C60 layers than previously reported.
The results reported by the authors help to advance the production of low-cost PV devices by improving the performance and scalability of ultra-thin SWCNT-based solar cells. Ultra-thin SWCNTs reported here could find potential use in other emerging technologies such as vertical field effect transistors and light-emitting diodes incorporating s-SWCNT injection layers.
Precision printing and optical modeling of ultrathin SWCNT/C60 heterojunction solar cells
Sarah L. Guillot, Kevin S. Mistry, Azure D. Avery, Jonah Richard, Anne-Marie Dowgiallo, Paul F. Ndione, Jao van de Lagemaat, Matthew O. Reese and Jeffrey L. Blackburn
Nanoscale, 2015, 7, 6556-6566. DOI: 10.1039/C5NR00205B
Dr Lee Barrett is a guest web writer for the Nanoscale blog. Lee is currently a postdoctoral researcher in the Centre for Molecular Nanometrology at the University of Strathclyde. His research is currently focused on the development of nanoparticle-based sensors and surface enhanced Raman scattering (SERS). Follow him on Twitter: @L_Bargie.
