Direct and Dry Deposited Single-Walled Carbon Nanotube Films Doped with MoO_x as Electron-Blocking Transparent Electrodes for Flexible Organic Solar Cells

Organic solar cells have been regarded as a promising electrical energy source. Transparent and conductive carbon nanotube film offers an alternative to commonly used ITO in photovoltaics with superior flexibility. This communication reports carbon nanotube-based indium-free organic solar cells and their flexible application. Direct and dry deposited carbon nanotube film doped with MoO_x functions as an electron-blocking transparent electrode, and its performance is enhanced further by overcoating with PEDOT:PSS. The single-walled carbon nanotube organic solar cell in this work shows a power conversion efficiency of 6.04%. This value is 83% of the leading ITO-based device performance (7.48%). Flexible application shows 3.91% efficiency and is capable of withstanding a severe cyclic flex test.