Techniques for increasing conductivity of carbon nanotube films are provided. In one aspect, a method for increasing conductivity of a carbon nanotube film includes the following steps. The carbon nanotube film is formed from a mixture of metallic and semiconducting carbon nanotubes. The carbon nanotubes are exposed to a solution comprising a one-electron oxidant configured to dope the semiconducting carbon nanotubes to increase a conductivity thereof, thereby increasing the overall conductivity of the film. The step of forming the carbon nanotube film can be performed prior to the step of exposing the carbon nanotubes to the one-electron oxidant solution. Alternatively, the step of exposing the carbon nanotubes to the one-electron oxidant solution can be performed prior to the step of forming the carbon nanotube film. A method of fabricating a transparent electrode on a photovoltaic device from a carbon nanotube film is also provided.