Takaoka G H, Takeuchi M, Ryuto H
Photonics and Electronics Science and Engineering Center, Kyoto University, Kyoto 615-8510, Japan.
Rev Sci Instrum. 2010 Feb;81(2):02B302. doi: 10.1063/1.3258426.
We have developed two types of liquid ion sources, one of which was a polyatomic ion source using liquid organic materials with a high-vapor pressure. Liquid materials such as octane and ethanol could be heated up to a maximum temperature of 100 degrees C, and the vapors were introduced into an ion source. They were ionized by an electron bombardment method and extracted from the ionizer. The ion current obtained at an extraction voltage of 2 kV was 230 microA for octane and several fragment ions such as alkyl ions were produced. On the other hand, another type of polyatomic ion source using alkyl naphthalene mixed with ionic liquid such as imidazolium dicyanamide has been developed. Instead of the electron bombardment method, a high-electric field method was used for the ion-emission from a sharp tip, because the vapor pressure of the liquid materials was relatively low. The threshold voltage was approximately 4.5 kV and the ion current of approximately 250 nA was obtained at an extraction voltage of 9.5 kV.
我们开发了两种类型的液体离子源，其中一种是使用具有高蒸气压的液体有机材料的多原子离子源。辛烷和乙醇等液体材料可加热至最高100摄氏度，其蒸气被引入离子源。它们通过电子轰击法电离并从电离器中引出。在2 kV的引出电压下，辛烷获得的离子电流为230 μA，并产生了几种碎片离子，如烷基离子。另一方面，已经开发出另一种多原子离子源，它使用与离子液体（如双氰胺咪唑鎓）混合的烷基萘。由于液体材料的蒸气压相对较低，因此采用高电场法从尖锐尖端进行离子发射，而不是电子轰击法。阈值电压约为4.5 kV，在9.5 kV的引出电压下获得了约250 nA的离子电流。
