Structural and optical properties of magnesium nitride formed by a novel electrochemical process

• Published in: Electrochimica acta Vol. 51; no. 1; pp. 56 - 60
• Main Authors: Toyoura, Kazuaki, Goto, Takuya, Hachiya, Kan, Hagiwara, Rika
• Format: Journal Article
• Language: English
• Published: Oxford Elsevier Ltd 05.10.2005; Elsevier
• Subjects: Bandgap; Chemistry; Electrochemical formation; Electrochemistry; Exact sciences and technology; General and physical chemistry; High temperature electrochemistry (including molten salts); Mg 3N 2; Molten salt; Optical property; Optical property; Electrochemical formation; Mg 3N 2; Bandgap; Molten salt; Magnesium nitride; Thermodynamic stability; Experimental study; Alkaline earth metal Compounds; Cyclic voltammetry; Mg3N2; Thermodynamic parameter; Optical properties; Potential pH diagram; Fused salt electrolyte; Ultraviolet visible spectrometry
• ISSN: 0013-4686; 1873-3859
• DOI: 10.1016/j.electacta.2005.04.004

The electrochemical formation of magnesium nitride (Mg 3N 2) films in LiCl–KCl containing Li 3N at 723 K was investigated. From a thermodynamic point of view, a potential- pN 3− diagram was constructed for the Mg–N system in an analogous fashion to Pourbaix diagrams for aqueous solutions. As a result, the thermodynamically stable region of Mg 3N 2 in LiCl–KCl–Li 3N was identified. XRD analysis revealed that Mg 3N 2 film was obtained by potentiostatic electrolysis of a magnesium electrode between 0.4 and 0.8 V (versus Li +/Li), and the structure of obtained Mg 3N 2 was anti-bixbyite ( a = 1.001 nm). Reflectance measurements clarified that assuming direct transition, the bandgap energy was 3.15 eV and assuming indirect transition, the bandgap energy was 2.85 eV.