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利用非模板水热法合成了Pd掺杂的SnO2纳米颗粒,并利用透射电镜(TEM)、X射线衍射(XRD)和X光电子能谱(XPS)表征了Pd掺杂对晶体结构、表面形貌、微观结构、热稳定性和表面化学状态的影响。研究发现:水热过程中Pd掺杂对形成的SnO2纳米颗粒大小几乎没有影响,在500°C以下的煅烧过程中,掺杂的Pd可以有效抑制颗粒的生长,但在700°C以上时颗粒生长迅速。XPS结果显示合成样品中Pd的化学状态有三种:Pd0、Pd2+和Pd4+,其中的主化学状态Pd4+有效促进了气敏性能的提高。为了同时提高气敏性能和热稳定性,Pd的最佳掺杂量为2.0%?2.5%(摩尔分数)。
Pd-doped SnO2 nanoparticles were synthesized by non-template hydrothermal method. The effects of Pd doping on the crystal structure, surface morphology and surface morphology were characterized by transmission electron microscopy (TEM), X-ray diffraction (XRD) and X-ray photoelectron spectroscopy , Microstructure, thermal stability and surface chemistry. The results showed that Pd doping had almost no effect on the size of SnO2 nanoparticles during the hydrothermal process. During the calcination at 500 ° C, the doping of Pd could effectively inhibit the growth of the particles. However, when the temperature was above 700 ° C, Grow rapidly. XPS results show that there are three chemical states of Pd in the synthesized samples: Pd0, Pd2 + and Pd4 +, in which the Pd4 + in the main chemical state effectively improves the gas sensitivity. In order to improve gas sensitivity and thermal stability at the same time, the optimal doping amount of Pd is 2.0% ~ 2.5% (mole fraction).