导电氧化钼的制备及表征

Synthesis and Characterization of Electroconductive Molybdenum Oxides

用金属肼盐热分解法,以钼酸铵为原料,用草酸和肼作为添加剂制备了草酸钼酸肼复合盐,并以此为前驱物在氮气保护下,于760℃热分解制得低价态氧化钼粉末。测定了产品的钼、NH4+的质量分数以及电阻率,并通过DSC-TGA、XRD以及BET比表面积测试等表征手段,考察了肼和草酸添加量,以及前驱物热分解时间和分解温度对产品性状的影响。结果表明,典型产品为MoO2,比表面积25 0m2/g,体积电阻率为0 0477Ω·cm,具有良好的导电性能,可以用作导电粉体材料。

Using the approach of thermolysis of metal hydrazonium,a kind of low-valent molybdenum dioxide powder was prepared by sintering a special precursor at 760 ℃ under nitrogen atmosphere.The precursor was prepared by reaction of ammonium molybdate 〔(NH_4)_6Mo_7O_(24)·4H_2O〕,with oxalic acid and hydrazine.Effects of hydrazine or oxalate amount and calcination time and temperatures of the precursor on the compositions and electric properties of the product were investigated by determining the contents of molybdenum and ammonium ion and measuring the electric resistivity.DSC-TGA,XRD and BET specific surface area analyzer were applied to characterize the final sample.Experimental results indicate that the typical product is MoO_2,BET specific surface area is 25.0 m^2/g,and volumetric electric resistivity equals to 0.0477 Ω·cm.It can be used as conductive material for its outstanding electroconductivity.