CAJ | 학술논문

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℃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℃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).
이용비모판수열법합성료Pd참잡적SnO2납미과립,병이용투사전경(TEM)、X사선연사(XRD)화X광전자능보(XPS)표정료Pd참잡대정체결구、표면형모、미관결구、열은정성화표면화학상태적영향.연구발현:수열과정중Pd참잡대형성적SnO2납미과립대소궤호몰유영향,재500℃이하적단소과정중,참잡적Pd가이유효억제과립적생장,단재700℃이상시과립생장신속.XPS결과현시합성양품중Pd적화학상태유삼충:Pd0、pd2+화Pd4+,기중적주화학상태Pd4+유효촉진료기민성능적제고.위료동시제고기민성능화열은정성,Pd적최가참잡량위2.0％-2.5％（마이분수).
SnO2 nano particles with various Pd-doping concentrations were prepared using a template-free hydrothermal method.The effects of Pd doping on the crystal structure,morphology,microstructure,thermal stability and surface chemistry of these nano particles were characterized by transmission electron microscope,X-ray diffractometer and X-ray photoelectron spectroscope respectively.It was observed that Pd-doping had little effect on the grain sizes of the obtained SnO2 nano particles during the hydrothermal route.During thermal annealing,Pd-doping could restrain the growth of grain sizes below 500 ℃ while the grain growth was promoted when the temperature increased to above 700 ℃.XPS results revealed that Pd existed in three chemical states in the as-synthesized sample as Pd0,Pd2+ and Pd4+,respectively.Pd4+ was the main state which was responsible for improving the gas-sensing property.The optimal Pd-doping concentration for better gas-sensing property and thermal stability was 2.0％-2.5％(mole fraction).