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采用柠檬酸溶胶-凝胶法,以乙醇为溶剂,制备得到形貌良好的铈锆固溶体Ce0.5Zr0.5O2,通过XRD,SEM,BET等手段进行了表征,XRD结果表明该法合成的Ce0.5Zr0.5O2具有四方晶相,无富铈或富锆相峰的出现。1000℃退火3 h后,表面积仍达25.1 m2.g-1。比表面积(SBET)和理论比表面积(SXRD)、晶粒尺寸(DXRD)和理论晶粒尺寸(SXRD)的计算比较,证明发生了颗粒团聚。根据XRD数据计算,Ce0.5Zr0.5O2的颗粒增长活化能为3.99 kJ.mol-1,较低的活化能归结为氧空位的产生。将制备的Ce0.5Zr0.5O2应用于催化碳酸二甲酯(DMC)的合成,催化效果良好。
The cerium-zirconium solid solution Ce0.5Zr0.5O2 with good morphology was prepared by using citric acid sol-gel method and ethanol as solvent. The XRD, SEM and BET were used to characterize the Ce0.5Zr0.5O2. 5Zr0.5O2 has a tetragonal phase, the presence of cerium-rich or zirconium-rich phase peaks. Annealed at 1000 ℃ for 3 h, the surface area still reached 25.1 m2.g-1. Comparisons of specific surface area (SBET) and theoretical specific surface area (SXRD), grain size (DXRD) and theoretical grain size (SXRD) proved that particle agglomeration occurred. According to XRD data, the activation energy of Ce0.5Zr0.5O2 particle growth is 3.99 kJ · mol-1, and the lower activation energy is attributed to the generation of oxygen vacancies. The prepared Ce0.5Zr0.5O2 catalyst for the catalytic synthesis of dimethyl carbonate (DMC), the catalytic effect is good.