NiO cathodic electrochemical deposition from an aprotic ionic liquid: Building metal oxide n–p heterojunctions

• Published in: Electrochimica acta Vol. 71; pp. 39 - 43
• Main Authors: Azaceta, Eneko, Chavhan, Sudam, Rossi, Paola, Paderi, Marzia, Fantini, Sebastien, Ungureanu, Mariana, Miguel, Oscar, Grande, Hans-Jurgen, Tena-Zaera, Ramon
• Format: Journal Article
• Language: English
• Published: Kidlington Elsevier Ltd 01.06.2012; Elsevier
• Subjects: Chemistry; Deposition; Electrochemistry; Electrodeposition; Electronic device; Electronics; Exact sciences and technology; General and physical chemistry; Ionic liquid; Ionic liquids; Metal oxide; Metal oxides; NiO; Scanning electron microscopy; Study of interfaces; Thin films; X-rays; Metal oxide; Electrodeposition; Electronic device; NiO; Ionic liquid; Nickel Oxides; Metal Oxides; Electrochemical reaction; Aprotic solvent; Heterojunction
• ISSN: 0013-4686; 1873-3859
• DOI: 10.1016/j.electacta.2012.03.093

NiO thin films have been successfully deposited by cathodic electrochemical deposition in N-butyl-N-methylpyrrolidinium bis(trifloromethanesulfonyl)imide room temperature ionic liquid (IL), giving an unambiguous proof of concept of the metal oxide electrodeposition in aprotic ILs without metal hydroxide formation as an intermediate phase. The electrochemical phenomena involved in the deposition process have been analyzed by cyclic voltammetry, pointing out that the electrochemical reduction of Ni2+ may be quenched in oxygenated IL electrolytes. The physico-chemical properties of the obtained NiO thin films have been characterized by electron scanning and atomic force microscopies, X-ray diffraction and Fourier transform infrared X-ray photo-electron spectroscopies. By taking advantage of the present electrodeposition route, ZnO/NiO heterostructures have been built. The current density-voltage characteristic of the resulting device exhibits clear rectifying behavior, with a rectification factor of 3×103 at V=±1V. This result anticipates a significant potential of the present electrochemical route in the metal oxide electronics.