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 μ 700 ω /sq to μ 2000 X/sq) increases with the decrease of acetonitrile feeding amount (from 200 lL to 10 lL). 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.