Formation Mechanism of Combined Crystals and Applications to Development of New Functional Materials

复合晶体的形成机理及其在新型功能材料开发中的应用

基本信息

批准号：
12450316
负责人：
MATSUOKA Masakuni
金额：
$ 9.02万
依托单位：
Tokyo University of Agriculture and Technology
依托单位国家：
日本
项目类别：
Grant-in-Aid for Scientific Research (B)
财政年份：
2000
资助国家：
日本
起止时间：
2000 至 2001
项目状态：
已结题

项目摘要

We, in the previous studies, observed the formation of combined crystals by the spontaneous nucleation of potassium chloride crystals on the surfaces of sodium chloride contacted with supersaturated NaCl - KC1 - H_2Oernary solutions. The present study aims to elucidate the mechanism of formation of the combined crystals and to investigate their possibilities of applications to new functional materials. For the NaCl - KC1 -H_2Oternary system, spontaneous nucleation of potassium chloride was induced during the steady growth of NaCl substrate. Deposition of potassium chloride crystals on the sodium chloride substrate crystals was clearly observed and the crystals deposited were found to be in the same orientation. From the observation of dissolving surfaces of sodium chloride substrate crystals placed in aqueous solutions that contained potassium chloride and were undersaturated with respect to sodium chloride, nucleation of potassium chloride was observed. The nucleation was caused by th … More e local high supersaturation created by the dissolution of sodium chloride into the mother liquor. The solution structures near the solid-liquid interface between sodium chloride crystals and NaCl - KQ - H_2Oternary solutions were studied by molecular dynamics simulations to elucidate the mechanism of formation of the combined crystals. The solution structures and the local compositions near the solid-liquid interfaces were completely different from those of the mother liquors. The formation of shallow grooves at the interface between sodium chloride substrate and potassium chloride deposit was observed, and the width and depth of the grooves were larger and the shape changed with time. This would be because the structure of the grooves was unstable and was therefore affected by moisture. The formation of combined crystals were also observed for the NaNO_ 3-KNO_3 -H_2O and NaCl - KNO_3 - H_2O ternary systems, and this result will be useful for the applications of the combined crystals to the new functional materials. Less

在先前的研究中，我们观察到通过氯化钾晶体的赞助核系统在氯化钠表面上与过饱和NACL -KC1 -KC1 -H_2Oernary溶液接触的晶体形成。本研究旨在阐明组合晶体的形成机理，并研究其对新功能材料的应用潜力。对于NaCl -KC1 -H_2oternary系统，在NaCl底物的稳定生长过程中诱导了钾的钾核系统。清楚地观察到氯化钾晶体在氯化钠晶体上的沉积，并发现沉积的晶体处于相同的方向。从观察到位于含有氯化钾的水溶液中的氯化钠底物晶体的溶解表面中，并且相对于氯化钠，氯化钾的成核被观察到了氯化钾的成核。核由氯化钠溶解到母液中产生的更多局部高过饱和引起。通过分子动力学模拟研究了氯化钠晶体和NaCl -KQ -H_2oternary溶液之间固定液体界面附近的溶液结构，以阐明合并晶体的形成机理。溶液结构和固定液体界面附近的局部组合物与母液的完全不同。观察到在氯化钠底物和氯化钾沉积物之间的界面处的浅凹槽的形成，凹槽的宽度和深度更大，形状随时间变化。这是因为凹槽的结构不稳定，因此受水分的影响。还观察到组合晶体的形成，对于纳米_ 3 -kno_3 -H_2O和NaCl -KNO_3 -H_2O三元系统，该结果将对组合晶体的应用在新功能材料中有用。较少的