热分析-质谱联用中逸出气体的脉冲热分析定量方法

利用脉冲热分析技术(PulseTA)实现对热分析-质谱(TA-MS)联用系统中逸出气体质谱信号的定量,考察了多种实验参数如不同载气流速、温度以及分析样品量等因素对热分析-质谱联用系统中逸出气体质谱信号定量校正的影响.实验结果表明,利用PulseTA对TA-MS联用系统中逸出气体CO2定量结果与理论计算值的相对误差约2.85%.同时利用TG-DTG-MS联用技术对氮化铟(InN)粉体的热分解行为进行研究,在氩气气氛下InN粉体的热分解过程一步完成,InN粉体在550～750℃得到相应的正离子质谱峰:N2+(m/z=28),所释放的N非常接近InN中N的理论含量.利用PulseTA技术检测到InN粉体受热分解放出氮气质量的实验测量值与理论计算值的相对误差约为1.36%.

Quantitative calibration of the evolved gases by TA-MS-PulseTA coupling techniques

Pulse thermal analysis （PulseTA） combined with TA-MS coupling techniques were used for a simultaneous characterization of the changes of mass and quantitative calibration of the evolved gases.The influence of several experimental parameters such as flow rate of the carrier gas,temperature and concentration of the analyzed species on the sensitivity of the mass spectrometric analysis in a TA-MS system has been investigated.The results showed that the relative error of this method between measured value and theoretical value was 2.85% for the quantitative calibration of the evolved CO2.Moreover,quantitative calibration of the evolved N2 formed during the thermal decomposition of InN sample was measured by TG-DTG-MS-PulseTA coupling techniques.The results showed a single-stage reaction and the MS spectra of N2＋（m/z=28） at 550-750 ℃ for the decomposition of InN sample under argon atmosphere.It was confirmed that the InN powder was obtained at 600 ℃ for 8 h by the nitridation of In2O3 with NH3 gas.The relative error of this method between measured value and theoretical value was 1.36% for the quantitative calibration of evolved N2.