Ultrasonic spray coating of conducting and transparent films from combined graphene and conductive nano filaments

An ultrasonic spray coating method of producing an optically transparent and electrically conductive film, said method comprising:

• (a) operating an ultrasonic spray device to form aerosol droplets of a first dispersion comprising first conducting nano filaments in a first liquid wherein said nano filaments have a dimension less than 200 nm;
• (b) forming aerosol droplets of a second dispersion or solution comprising a graphene material in a second liquid;
• (c) depositing said aerosol droplets of a first dispersion and said aerosol droplets of a second dispersion or solution onto a supporting substrate;
• and
• (d) removing the first liquid and the second liquid from the droplets to form said optically transparent and electrically conductive film, which is composed of said first conducting nano filaments and said graphene material having a nano filament-to-graphene weight ratio of from 1/99 to 99/1, wherein said film exhibits an optical transparence no less than 80% and sheet resistance no higher than 300 ohm/square.