Semiconductor Single Crystal-gel Composite

As a simple and effective technology to grow crystals of high quality, gel method has been applied in many areas. After Nickl and Henisch discovered silica gel could be incorporated in calcite crystal in 1969, more and more gel-incorporated-crystals were reported. Up to now, agarose and silica gels were incorporated in varied crystals of calcite, protein, amino acid to form single crystal composite where a 3D network penetrated inside. Interestingly, these composites still diffract X-rays and/or electron beams as single-crystals. Although as gel-incorporated-crystals had been successfully prepared, there still a long way to go to apply them in daily life. And there are a few ways we could take into consideration:using functional crystals; using functional gel; introducing another functional Ingredient. In this work, we tried to grow semiconductor crystals in gels to testify whether they could also incorporate gels. We had prepared lead sulfide, lead iodide crystals in agarose and silica gels to explore the possibility.In the first chapter, we introduced the property and growth method of single crystal. Also, we highlight gel method, the method we use in our work. Then, the discovery, recent progress and the unique property of gel incorporated single crystal were reviewed.In the second part, we prepared lead sulfide crystals in both silica and agarose gels to obtain gel-incorporated single-crystal composites. Their morphologies and internal structures were characterized. In addition, the effects of gel density, temperature and pH on the formation of the composites were investigated.In chapter three, we prepared the crystal of PbCl2 and PbI2 to see whether they could incorporate gels. And we found the incorporated amounts of gel materials was effected by the crystal morphology. And in the case of PbI2, we found the band gap changed after gel was incorporated.We also tried to grow the Cu2O-Gu crystal in agarose and silica gel, and obtained the interesting core-shell structure of Cu2O-Cu crystal in silica gel, additionally the effect of reactant concentration was investigated.