Our lab has a Thermo Finnigan Triton Plus multi-collector thermal ionization mass spectrometer (TIMS) which was installed and commissioned in November 2018. The supporting platform includes a clean room and an ICP-OES (ThermoFisher iCAP 7200 plus), which supports sample preparation, elemental determination, chemical purification, and isotope measurement.
Triton plus TIMS is equipped with nine Faraday detectors and suitable for the measurement of isotopic compositions in high precision. The purified sample are heated and ionized on the evaporating filament. After being accelerated and focused by the electric field, the ions are deflected in the magnetic field and detected by the corresponding Faraday Cups according to the mass-charge ratios of different isotopes. The isotopic composition can be evaluated with isotopic signals. Compared with MC-ICPMS, TIMS yields less mass dependent fractionation and more stable signatures during the measurement. Thus, TIMS is widely used in the measurement of multiple isotopic systems in extraterrestrial and terrestrial samples with high precision.
Our lab focuses on the measurement of non-traditinal stable isotopic compositions (e.g. Cr, Ni, Mo, and W). The mass independent fractionation measurements are mainly applied to extraterrestrial samples for short-lived radiogenic chronometer and nucleosynthetic anomalies. The mass dependent fractionation measurements are using the double-spike technique. The measurements of other isotopes will be carried out in the future.