铌酸盐纳米晶体的制备、表征及其性能的研究

发布时间：2018-04-05 13:36

  本文选题：铌酸钾　切入点：铌酸钠　出处：《深圳大学》2015年硕士论文

【摘要】：一维铌酸盐纳米晶体具有很高的电光系数和非线性光学系数,对于信息、物理以及生物科学的发展有着重要的意义。一维纳米材料具有各向异性,使其拥有比二维纳米材料更优越的性能。但一维铌酸盐在合成和应用上还存在许多问题。本论文将综合考虑理论和实验这两方面的问题,以铌酸盐技术研究为主导,以一维铌酸盐纳米晶体可控合成、表征和性能为主要研究内容,解决了一维铌酸盐纳米晶体合成过程中产率低、形貌不可控等问题。保持温度为150℃,碱液浓度为10mol/L不变,通过改变其他反应条件,制备出针状和树状铌酸钾钠晶体。以市售Nb2O5为原料,在K和Na摩尔比为3:17的条件下,水热反应5天,合成了直径为100-500nm的针状铌酸钾钠晶体,与合成针状铌酸钾钠晶体相同的条件,使用Nb2O5纳米棒作为反应原料替代市售Nb2O5后,合成出树状的铌酸钾钠晶体。在传统水热法制备KNb O3的基础上,分别使用Nb2O5纳米棒和KNb3O8纳米棒作为原料和模板替代传统方法使用的市售Nb2O5粉体后,合成出直径分别为100-200nm和100-150nm的KNb O3纳米棒。使用Nb2O5纳米棒合成结晶程度较为完整的KNb O3纳米棒需要5d,而使用KNb3O8纳米棒时,只需12h就能合成出纯相KNb O3纳米棒,极大的缩短了反应时间。同样,在传统水热法制备Na Nb O3的基础上,Nb2O5纳米棒作为原料和模板,合成出直径为500-800nm的Na Nb O3纳米棒。采用铌粉作为原料反应原料时,合成出直径为50-150nm的Na Nb O3纳米棒,极大的减小了产物Na Nb O3纳米棒的粒径。在传统熔盐法制备KNb3O8的基础上,如果在粉体的原料中添加适量的Nb2O5纳米棒后,可以合成出粒径为150-500nm的KNb3O8纳米棒,大大的减小了产物的直径。将直径为30-50nm的纳米银颗粒通过银镜反应附着于KNb3O8纳米棒后,KNb3O8纳米棒镀银后荧光性能极大的增强,荧光强度变成原来的4倍。同时,KNb3O8纳米棒镀银后光催化效率极大的提高,光催化效率变为原来的2倍。KNb3O8纳米棒和KNb O3纳米棒的二次谐波信号随着偏振片的旋转,强度发生明显改变。说明实验所制备的KNb3O8纳米棒和KNb O3纳米棒具有较强的非线性光学性能。
[Abstract]:One-dimensional niobate nanocrystals have high electro-optic and nonlinear optical coefficients, which are of great significance for the development of information, physics and biological science.One-dimensional nanomaterials have anisotropy, which makes them superior to two-dimensional nanomaterials.However, there are still many problems in the synthesis and application of one-dimensional niobate.In this thesis, the theoretical and experimental problems will be comprehensively considered, and the study of niobate technology will be the dominant, and the controllable synthesis, characterization and properties of one-dimensional nanocrystalline niobate will be the main research contents.The problems of low yield and uncontrollable morphology during the synthesis of one dimensional niobate nanocrystalline were solved.By changing other reaction conditions, the needle-like and dendritic potassium sodium niobate crystals were prepared by keeping the temperature at 150 鈩，

本文编号：1714986