Mo-La材料固-液喷雾掺杂过程掺杂物反应机制分析

摘要

通过对硝酸镧晶体进行差热分析,获得TG、DTG和DSC曲线,进而确定3个温度拐点。在这3个温度下,对硝酸镧进行空气气氛的热分解试验和固-液喷雾掺杂工艺模拟试验,并对其反应产物进行 XRD 分析。按照MoO2-50La(NO3)3的化学配比,进行Mo-La材料的固-液喷雾掺杂试验,对掺杂MoO2进行XRD分析。这3试验结果证明,在传统喷雾掺杂过程中,硝酸镧无论呈晶体形式还是水溶液形式,均只通过脱水反应转变为La(NO3)3.4H2 O,而不会发生热分解产生La2 O3、NO和/或NO2,掺杂过程产生的氮氧化合物烟气污染是由于硝酸分解所得。并分析了硝酸的来源。%In the three break temperatures, which were obtained by TG/DTG/DSC curves of lanthanum nitrate crystal, the air thermal decomposition and solid–liquid spray doping simulation experiments of lanthanum nitrate crystal were carried out, and their products were analyzed by XRD. Meanwhile, according to the chemical formula of MoO2-50La(NO3)3, the spray doping processing of Mo-La material is undergone, and doped MoO2 was analyzed by XRD. The results demonstrated that during the traditional solid – liquid spray doping processing, lanthanum nitrate, in the form of crystal or aqueous solution, would not be decomposed to La2 O3 and NO or NO2 , but be con-verted into La(NO3)3. 4H2O by the dehydration reaction, and that the oxynitride gas pollution produced by the pro-cessing was due to decomposition of HNO3 . And the source of HNO3 is theoretically presented.