贵金属催化剂对氧化镍气敏特性的影响

EFFECTS OF NOBLE METAL CATALYSTS ON GAS SENSING PROPERTIES OF NiO

采用均匀沉淀法合成了氧化镍（ＮｉＯ）气敏微粉，利用浸渍法对氧化镍材料进行了掺杂，用Ｘ射线衍射、电子衍射和透射电镜对材料的陶瓷微结构进行了研究．实验结果表明：合成材料为颗粒状非晶体，颗粒尺寸＜１μｍ；该材料为Ｐ型半导体材料，对Ｃ２Ｈ５ＯＨ具有较高灵敏度，Ａｇ的掺杂能提高ＮｉＯ的气体灵敏度，Ｐｄ，Ｐｔ，Ａｕ，Ｒｕ，Ｒｈ的掺杂不能有效地提高其气体灵敏度，但可改善ＮｉＯ的气敏选择性．

The gas sensing macropowder of NiO were synthesised by homogeneous precipitation, NiO macropowder doped with noble metal(Ag,Au,Pd,Pt,Ru,Rh) were prepared by means of impregnation.The microstructure of the materials were studied by XRD,TEM and ED.It can be seen from the experimetal results,the paticle size of NiO micropowder is less than 1 μm,it is noncrystal semiconductor of P type.The gas sensitivity of NiO to C 2H 5OH and gasoline is higher than it to H 2,CH 4 and C 4H 10 .Addition of noble metal to NiO can not greatly increased the gas sensitivity of NiO,but it can improve the gas stability of NiO.