液氨介质中多孔硅粉对钙和铕的吸附性能

Study on adsorption properties of porous silicon powder to calcium and europium in liquid ammonia medium

通过吸附钙和铕来改变多孔硅的表面状态,以提高其发光效率。采用金属辅助化学腐蚀法制备多孔硅粉,以液氨为介质溶解金属钙和铕,使钙和铕吸附在多孔硅表面。利用扫描电子显微镜、傅里叶变换红外光谱仪、能谱仪对多孔硅粉特性以及多孔硅粉在液氨介质中对金属钙和铕的吸附性能进行表征。结果表明:金属辅助化学腐蚀硅粉表面的孔径受腐蚀液温度的影响,当腐蚀液温度为40℃时,硅表面孔径最均匀且孔径最大;在液氨介质的作用下,多孔硅粉吸附氨分子基团,形成Si-(NH2)2;多孔硅通过液氨介质能够吸附金属离子,使金属胺钙均匀沉积在多孔硅粉表面,金属胺铕非均匀沉积在多孔硅表面。

The surface state of porous silicon was changedby adsorbing calcium and strontium to improve its luminescence efficiency.Porous silicon powder was prepared by metal-assisted chemical etching method,and calcium and europium were dissolved in liquid ammonia medium so that calcium and europium were adsorbed on the surface of porous silicon.The characteristics of porous silicon powder and the adsorption properties of porous silicon powder to calcium and europium in liquid ammonia medium were characterized by Scanning electron microscopy(SEM),Fourier transform infrared spectroscopy(FTIR)and Energy spectrometer(EDS).The results showed that the pore size of the surface of the metal-assisted chemically etched silicon powder was affected by the temperature of the etching solution.When the temperature of the etching solution was 40 ℃,the surface diameter of the silicon surface was most uniform and the pore diameter was the largest.Under the action of liquid ammonia medium,porous silicon powder adsorbed ammonia molecular groups to form Si-(NH2)2;porous silicon could adsorb metal ions through liquid ammonia medium,so that the metal amine calcium was uniformly deposited on the surface of porous silicon powder,and the metal amine europium was unevenly deposited on the surface of porous silicon.