摘要
针对纯的镍铁尖晶石纳米材料对气体灵敏度较低问题,以硝酸铁、硝酸镍和硝酸镁作为反应物,柠檬酸作为凝胶剂,采用溶胶凝胶结合自蔓延燃烧工艺合成Ni1-xMgxFe2O4型纳米粉体,研究了金属镁离子掺杂对镍铁尖晶石晶体结构及气体灵敏度的影响.x-射线衍射仪(XRD)分析和扫描电子显微镜(SEM)分析结果表明:干凝胶在250℃自燃所得的粉体即为NiFe2O4尖晶石相,Mg2+在NiFe2O4晶格中优先占据B位,部分占据A位.采用600℃热处理后的样品颗粒尺寸为30～50nm.气敏性能测试结果表明:当x为0.2,最佳工作温度为300℃时,Ni1-xMgxFe2O4型气敏元件对丙酮气体的灵敏度最高.
In order to improve the gas sensitivity of pure nickel ferrite nano-material,Ni1-xMgxFe2O4 nano-powder was prepared by sol-gel plus self-propagating combustion method with taking iron nitrate,nickel nitrate and magnesium nitrate as reactants and citric acid as gel. The influence of blending Mg2＋ on both crystal structure and gas sensitivity of nickel ferrite was characterized. The XRD and SEM analysis results indicate that the powder synthesized by self-propagating combustion of dry gel at 250℃ is single NiFe2O4 phase,and Mg2＋ ions preferentially occupy the B sites and partially occupy the A sites in the crystal lattice of NiFe2O4. The particle size of the sample heat-treated at 600℃ is about 30 to 50nm. The testing results of gas sensitivity reveal that when x is 0.2 and the optimal operating temperature is 300℃,the sensitivity of Ni1-xMgxFe2O4 gas sensor to acetone gas is the highest.
出处
《沈阳工业大学学报》
EI
CAS
2010年第4期380-384,共5页
Journal of Shenyang University of Technology
基金
山东省中青年科学家科研奖励基金资助项目(2006BS04035)
关键词
纳米粉体
镍铁尖晶石
镁离子
掺杂
溶胶凝胶法
自蔓延燃烧
晶体结构
灵敏度
nano-powder
nickel ferrite
Mg2＋ ion
blending
sol-gel method
self-propagating combustion
crystal structure
gas sensitivity
