N-Type Cu[sub 2]O by Electrochemical Doping with Cl

Abstract

Cuprous oxide (Cu 2 O) is naturally p-type, which has prevented an efficient Cu 2 O solar cell. n-Type doping of Cu 2 O is demonstrated during electrochemical deposition by adding a chlorine (Cl) precursor to the aqueous solution. Current-voltage characterization reveals that the resistivity of undoped Cu 2 O by electrochemical deposition is ∼ 40 MΩ cm, while that of electrochemically doped Cu 2 O with Cl is significantly reduced to as low as ∼7 Ω cm. X-ray diffraction confirms that the films are pure Cu 2 O. Photocurrent measurements verify that Cl-doped Cu 2 O is n-type. The solution-based doping method is particularly suitable for low-cost, large-area, and high-throughput fabrication of Cu 2 O solar cells.