摘要
采用Pechini方法,以柠檬酸为配位剂与金属离子配位,在Pt/Ti/SiO2/Si基片上制备了多晶铌酸锂(LiNbO3)薄膜。以13C核磁共振、拉曼光谱和红外光谱分析研究了柠檬酸与金属离子的配位情况,提出了一种Nb-柠檬酸配合物可能的分子结构,即柠檬酸作为三齿配体,以端羧基、-OH和中间羧基与Nb离子配位。以TG-DTA对Li-Nb凝胶前驱体的热分解历程进行分析,以拉曼光谱和XRD分析了LiNbO3薄膜在不同温度下热处理的相组成和结构。结果表明,600℃下退火2h可得到单相多晶LiNbO3薄膜,薄膜表面致密、平整,晶粒的平均尺寸为50 nm。
Lithium niobate thin films have been deposited on Pt/Ti/SiO2/Si （100） substrates by using Pechini method. The metal cations are chelated in an aqueous solution with citric acid as chelating agent. The chemistry of the metal-citric acid solutions has been characterized by carbon nuclear magnetic resonance spectroscopy （%13C NMR）, Raman spectroscopy and Fourier transform infrared （FTIR）. A possible molecular structure of Nb-citric acid complex is proposed, i.e. citric acid coordinates to Nb^5＋ ion through one terminal carboxyl group, the hydroxyl group, and the central Carboxyl group as a tridentate ligand. The thermal decomposition of Li-Nb precursors gels has been studied by TG/DTA and films annealed at different temperatures have been characterized by XRD and Roman spectroscopy. The results show that by heat-treatment at 600 ℃ for 2 h, polycrystalline LiNbO3 thin films with smooth and crack-free surface could be achieved. The average grain size of the films is about 50 nm.
出处
《无机化学学报》
SCIE
CAS
CSCD
北大核心
2006年第11期1957-1961,共5页
Chinese Journal of Inorganic Chemistry
基金
黑龙江省自然科学基金
哈尔滨工业大学跨学科交叉基金(No.HIT.MD.2003.18)资助项目。
