Galvanostatic electrochemical deposition of Cu-doped Mg(OH)2 thin films and fabrication of p-n homojunction

• Published in: Materials research bulletin 2021-05, Vol.137, p.111207, Article 111207
• Main Authors: Kang, Jihye, Keikhaei, Mansoureh, Li, Tong, Ichimura, Masaya
• Format: Article
• Language: English
• Subjects: Electrochemical deposition; Magnesium hydroxide; Thin film; Transparent conducting oxides; X-ray photoelectron spectroscopy
• ISSN: 0025-5408; 1873-4227
• DOI: 10.1016/j.materresbull.2021.111207

[Display omitted] •Cu-doped Mg(OH)2 is deposited by galvanostatic electrochemical deposition (ECD).•The deposited films are semiconducting.•The films can be p-type or n-type, depending on deposition condition.•p-n homojunction of Mg(OH)2 is fabricated for the first time. Conduction type control of transparent conducting materials is challenging. In this study, novel conductive p-type and n-type Cu-doped Mg(OH)2 thin films are obtained. The thin films are fabricated by both potentiostatic and galvanostatic electrochemical deposition with solutions containing 20 mM Mg(NO3)2 and different amounts (1–20 mM) of Cu(NO3)2. All specimens show high transmittance values more than 90 % in the visible range. The galvanostatically deposited films are n-type with 1 mM Cu in the solution while they are p-type with Cu amount of 3 mM or more. X-ray photoelectron spectroscopy results ascertain the presence of Cu+ and less amount of Cu2+ in the films. A p-n homojunction is fabricated by potentiostatic and galvanostatic deposition, and its current-voltage characteristic shows rectification properties.