Ga2O3-NiO复合氧化物的溶胶-凝胶法制备和气敏性能

用溶胶-凝胶法制备了Ga2O3-NiO复合金属氧化物气敏材料,对其相组成、电导和气敏性能作了研究.结果表明:镍镓物质的量比n(Ni2＋) : n(Ga3＋)=0.7～0.9:2、800 ℃下热处理4 h,得到纯相尖晶石型复合金属氧化物NiGa2O4.缺陷GaNi×的反应(GaNi×→GaNi’＋h●),使NiGa2O4呈p型半导体. n(Ni2＋) : n(Ga3＋)=1:2凝胶粉在800 ℃下热处理4 h,所得纳米微粉制作的元件在313 ℃工作温度下对C2H5OH有较高灵敏度和良好的选择性.

The Preparation and Gas-sensing Properties of Ga2O3-NiO Complex Oxide by Sol-gel Method

Ga2O3-NiO Complex Oxide gas-sensing materials were prepared by sol-gel method. Effects of heat-treatment temperature and different n(Ni2＋) : n(Ga3＋) ratios on the phase constituents were characterized by XRD, IR and ICP, respectively. The conductance-temperature and gas-sensing properties of Ga2O3-NiO were investigated. The results demonstrate that pure phase NiGa2O4 can be obtained when the ratio of Ni2＋ to Ga3＋(n(Ni2＋) : n(Ga3＋)) is 0.7～0.9 : 2 and heat-treatment is carried out at 800 ℃ for 4 hours. Because of the reaction GaNi×→GaNi’＋h●, NiGa2O4 is a p-type semiconductor and exhibits high sensitivity and good selectivity to C2H5OH.