Neumann Andreas, Kahlenberg Volker, Lerche Ian, Stöber Stefan, Pöllmann Herbert
Institute of Geoscience and Geography, Martin-Luther-University Halle-Wittenberg, Von-Seckendorff-Platz 3, D-06120 Halle (Saale), Germany.
Institute of Mineralogy and Petrography, University of Innsbruck, Innrain 52, A-6020 Innsbruck, Austria.
ACS Omega. 2024 Mar 25;9(14):15781-15803. doi: 10.1021/acsomega.3c06960. eCollection 2024 Apr 9.
Two synthesis routes of the zircon-hafnon solid solution series were carried out. The high-temperature route uses the growth of single crystals via a flux mixture that has been cooled down slowly from 1400 °C over 4 weeks. The reaction products were colorless and idiomorphic without byproducts. The hydrothermal tetraethoxysilane (TEOS)-based route represents the low-temperature method at 200 °C for approximately 7 days. The hydrothermal route yielded a white powder and scanning electron microscopy analysis thereof did not reveal any specific idiomorphic properties. However, the synthesis also featured some byproducts besides the zircon-hafnon solid solutions. Thermogravimetric analysis coupled with differential scanning calorimetry, and mass spectroscopy indicated, that hydrothermal reaction products feature the presence of organic residues originating from the starting materials. However, a specific dependency on the hafnium content could not be observed due to the data scatter. Infrared (IR) analysis revealed the presence of Zr/Hf-oxides. The structural characterization demonstrated that properties change constantly with the hafnium amount, however, gradual variations of some properties related to the composition of the solid solution series depend in part on the synthesis route, considering the / ratio and IR modes. Furthermore, analyses of the single crystals by Raman spectroscopy and μXRF suggested a nonequilibrated crystal growth based on the starting composition.
开展了锆铪固溶体系列的两种合成路线。高温路线是通过助熔剂混合物生长单晶，该混合物已从1400℃缓慢冷却4周。反应产物无色且呈自形晶，无副产物。基于四乙氧基硅烷（TEOS）的水热路线是在200℃下进行约7天的低温方法。水热路线得到白色粉末，对其进行扫描电子显微镜分析未发现任何特定的自形晶特性。然而，该合成除了锆铪固溶体之外还产生了一些副产物。热重分析结合差示扫描量热法和质谱表明，水热反应产物具有源自起始原料的有机残留物。然而，由于数据分散，未观察到对铪含量的特定依赖性。红外（IR）分析揭示了Zr/Hf氧化物的存在。结构表征表明，性能随铪含量不断变化，然而，考虑到/比率和IR模式，与固溶体系列组成相关的一些性能的逐渐变化部分取决于合成路线。此外，通过拉曼光谱和μXRF对单晶进行的分析表明，基于起始组成存在非平衡晶体生长。
