Synthesis of nitrogen-doped carbon thin films and their applications in solar cells

N-doped carbon thin films (N-CFMs) on copper foils are synthesized by using acetonitrile (CH3CN) as liquid carbon and nitrogen precursors in a chemical vapor deposition system. Effect of acetonitrile feeding amount on the optical transmittance and electrical conductivity of N-CFMs are investigated. It is found that both the transmittance (from ∼41% to ∼75%) and sheet resistance (from ∼700 Ω/sq to ∼2000 Ω/sq) increases with the decrease of acetonitrile feeding amount (from 200 μL to 10 μL). Schottky junction solar cells based on n-type silicon and as-synthesized N-CFMs demonstrate power conversion efficiencies of up to ∼1.55%, showing their potential applications in photovoltaic areas.