【摘要】 采用改进的浓度控制的络合解络法在硅凝胶中生长出形状规则的CuI单晶。通过分光光度法测量铜离子浓度,分析了硅凝胶中络合物浓度和浓度梯度对晶体生长的影响。实验发现:要获得形貌规则且尺寸较大的CuI单晶,在晶体生长区必须维持一个低而稳定的络合物浓度和浓度梯度。就浓度递减法而言,生长区的浓度和浓度梯度一般可分别控制在0.01～0.03mol/L范围和0.012mol/(L·cm)左右,这样生长区的过饱和度可以维持在一个使晶体缓慢生长的水平。为更好地调控凝胶中络合物的浓度分布,通过浓度递增法研究了络合物的扩散规律,得到其平均扩散系数为1.521×10-5cm2/s,这一结果可为实验方案的进一步优化提供依据。更多还原

【Abstract】 CuI single crystal was grown in silica gel using the decomplexation method modified by concentration programming. The influence of the concentration and gradient of CuI·HI complex in silica gel on the crystal growth was studied by measuring the con- centration of copper ions with spectrophotometry. The results show that it is necessary to maintain low and stable values of both the concentration and its gradient of the complex, in order to grow a CuI single crystal with a regular shape and large size. When the con- centration of feed solution was decreased successively, the concentration and its gradient of the complex in the region of crystal growth had to be controlled in the range of 0.01—0.03 mol/L and at about 0.012 mol/(L?cm) respectively, so that the supersaturation of the CuI·HI complex could be kept at a value that could allow the CuI crystal to grow gradually. In order to control the variation of the concentration of CuI·HI complex in gel, the diffusion rule of the complex was studied by increasing the concentration of the feed solution. The average diffusion coefficient was calculated as 1.521×10-5 cm2/s. The results indicate that this could prove to be a useful method for optimizing experimental procedures.更多还原