Ca2+离子掺杂对γ-Ce2S3合成温度及热稳定性的影响

Effect of Ca2+-Doping on Synthesis Temperature and Heat Stability of γ-Ce2S3

以CeCl3·7H2O、CaCl2·2H2O和C2H2O4·2H2O为原料,在制备钙铈氧化物前驱体基础上,再以Ar气为载气、CS2为硫源对钙铈氧化物前驱体进行硫化合成Ca2+掺杂的γ-Ce2S3色料。通过X射线衍射(XRD)、紫外-可见漫反射光谱(UV-Vis)及差热-热重分析(TG-DTA)等技术手段表征了色料的结构和性能。结果表明,Ca2+掺杂能够明显降低γ-Ce2S3的合成温度,当n(Ca2+):n(Ce3+)≥0. 16时,在900℃硫化150 min即可获得纯相的γ-Ce2S3,与不掺杂时合成γ-Ce2S3的温度相比降低了300℃左右。同时,Ca2+掺杂能够提升γ-Ce2S3的抗氧化能力,当n(Ca2+):n(Ce3+)=0. 64时,氧化放热峰的温度由不掺杂时的490. 6℃提高至541. 0℃。

CeCl3·7H2O,CaCl2·2H2O and C2H2O4·2H2O were used as raw materials to prepare Ca2+-doped cerium oxalate by the coprecipitation method. The Ca2+-doped cerium oxalate was calcined to obtain Ca2+-doped cerium oxide precursor. Ca2+-doped γ-Ce2S3 was achieved by vulcanizing precursors in an Ar atmosphere using CS2 as the sulfur source. Pigments were characterized by X-ray diffraction( XRD),energy dispersive spectrometer( EDS),color analyzer,UV-Vis spectrophotometer and thermogravimetric analysisdifferential thermal analysis( TG-DTA). The results show that Ca2+-doping can lower the synthesis temperature and improve the thermal stability of pigments in air. When the ratio of n( Ca2+): n( Ce3+) ≥0. 16,pure phase γ-Ce2S3 can be obtained by vulcanizing at 900 ℃ for 150 min. The synthesis temperature of doped γ-Ce2S3 decrease by 300 ℃ compared with undoped γ-Ce2S3. When the n( Ca2+):n( Ce3+) is 0. 64,the oxidation exothermic peak of Ca2+-doped γ-Ce2S3 increases from 490. 6 to 541. 0 ℃.