氧化钨物理特征的分析

对铵钨青铜((NH_4)_(0.5)WO_3,ATB)、氢钨青铜(H_(0.33)WO_3,HTB)、紫色氧化钨(W_(18)O_(49),TVO)和蓝色氧化钨(WO_3+WO_(2.9),TBO)4种氧化钨粉的氮气吸附/脱附等温线数据的分析,获得了其表面积、微孔体积、微孔分布、中孔体积、平均孔径和分数维维数等物理参数。结果表明:TVO粉末具有最大的中孔体积、最小的微孔体积、最窄的孔径分布、最小的分数维维数和最大的平均孔径,有利于氢还原制取超细钨粉,而不利于掺杂工艺。HTB粉末具有最大的微孔体积,最宽的孔径分布,最高的分数维维数和最小的平均孔径,对于掺杂工艺来说是有利的。ATB和TBO的上述参数介于TVO和HTB的参数之间。

Determination of physical characterization of tungsten oxides

The physical characterization of surface area, micropore volume, micropore size distribution, mesopore volume, average pore diameter and fractal dimensions of four tungsten oxides of ATB (ammonium tungsten bronze, (NH_4)_(0.5) WO_3), HTB (hydrogen tungsten bronze, H_(0.33) WO_3), TVO (violet tungsten oxide, W_(18) O_(49)) and TBO (tungsten blue oxide, WO_3+WO_(2.9)) were evaluated from analysis of nitrogen adsorption-desorption isotherm data. The analysis of the adsorption-desorption isotherm data reveals that TVO with the largest mesopore volume, the smallest micropore volume, the narrowest micropore size distribution, the lowest fmctal dimension value and the biggest average pore diameter is advantageous for hydrogen reduction during fine tungsten powder production process and disadvantageous for doping process; HTB with the largest micropore volume, the widest micropore size distribution, the highest fractal dimension value and the smallest average pore diameter is favorable for doping process, and characterization properties of ATB and TBO in this investigation are just between TVO's and HTB's. The results show that that it is a preferable method to investigate the physical characterization of oxides by using adsorptiondesorption isotherms in this study and the physical characterization of tungsten oxides should be taken into account before they are used in reduction process or in doping process.