Gas chromatograph-mass spectrometer comprising an ion source, the walls of which are realized or covered with at least one layer of graphene. Thus realized, the gas chromato graph-mass spectrometer proves to be particularly suited to the analysis samples containing hydrogen in addition to the substances to be analyzed. This situation generally occurs when the mass spectrometer is coupled to a gas chromatograph that utilizes hydrogen as the carrier gas.

Method for producing multiply-charged helium nanodroplets and charged dopant clusters and nanoparticles out of the helium nanodroplets, the method comprising: producing neutral helium nanodroplets in a cold head (1) via expansion of a pressurized, pre-cooled, supersonic helium beam of high purity through a nozzle (3) into high vacuum with a base pressure under operation preferably below 20 mPa, ionizing the helium nanodroplets by electron impact (15), wherein the electron impact (15) leads to multiply-charged helium nanodroplets, doping the charged helium nanodroplets with dopant vapor in the pickup cell (19), wherein the doped nanodroplets form cluster ions with the initial charges acting as seeds, wherein the size of the nanoparticles can vary from a few atoms up to 105 atoms by arranging the size of the neutral helium nanodroplets, the charge of the helium nanodroplets and the density of dopant vapor in the pickup cell (19).

An analyzer according to the present invention includes an electron emission element, a detector, an electric field generator, an electrostatic gate electrode, and a controller, in which the electron emission element includes a lower electrode, a surface electrode, and an intermediate layer, and directly or indirectly generates anions by electrons emitted in an ionization region between the electron emission element and the electrostatic gate electrode, the electrostatic gate electrode controls injection of the anions into a drift region between the electrostatic gate electrode and the detector, the detector detects the anions move through the drift region by a potential gradient, and the controller applies a pulse voltage between the lower electrode and the surface electrode, and applies a voltage to the electrostatic gate electrode such that the electrostatic gate electrode injects the anions into the drift region during a time when the pulse voltage is on.

The invention relates to an ionization device with an ionization space formed in a container, an inlet system for supplying a gas to be ionized to the ionization space, an electron source having at least one filament for supply of an electron beam to the ionization space, and an outlet system for letting the ionized gas out of the ionization space. Electron optics having at least two electrodes are disposed between the filament and the ionization space

An ionizer 1 including an ionization chamber 10, a sample gas introduction port 14 provided in the ionization chamber 10 for introducing sample gas, an electron beam emitting section 11 which emits an electron beam toward the ionization chamber 10, electron beam passage openings 10a and 10b which are formed on a path of the electron beam emitted from the electron beam emitting section 11 on a wall of the ionization chamber 10 and has a length in a direction of the path longer than a width of a cross section orthogonal to the direction, and an ion outlet 10c provided in the ionization chamber 10 for emitting an ion of the sample gas generated by irradiation with the electron beam, and a mass spectrometer 60 including the ionizer 1.

Certain configurations of an ionization source comprising a multipolar rod assembly are described. In some examples, the multipolar rod assembly can be configured to provide a magnetic field and a radio frequency field into an ion volume formed by a substantially parallel arrangement of rods of the multipolar rod assembly. The ionization source may also comprise an electron source configured to provide electrons into the ion volume of the multipolar rod assembly to ionize analyte introduced into the ion volume. Systems and methods using the ionization source are also described.

An ion generation apparatus according to the present invention includes an electron emission device, an opposite electrode, and a controller, the electron emission device includes a lower electrode, a surface electrode, and an intermediate layer provided between the lower electrode and the surface electrode, the opposite electrode is provided to be opposite to the surface electrode, and the controller is provided to apply a voltage to the surface electrode, the lower electrode, or the opposite electrode such that a potential of the surface electrode becomes higher than a potential of the lower electrode and a potential of the opposite electrode in a positive ion mode.

In order to suppress a charge-up in an ion source configured to ionize a component contained in a sample gas, a mass spectrometer according to the present invention is provided with an ion source (3) including: an ionization chamber (30) having an ion ejection opening (301) and internally having a space substantially separated from an outside area; a repeller electrode (31), located within the ionization chamber, for creating an expelling electric field which acts on an ion generated within the ionization chamber to expel the ion through the ion ejection opening to the outside area; and a voltage generator (7) configured to selectively apply, to the repeller electrode, a first voltage for creating the expelling electric field and a second voltage for creating a charge-up-removing electric field, where the second voltage is a positive voltage having a larger absolute value than the first voltage.

An ion source assembly for use in a mass spectrometer comprises a first anode defining a first ionization volume and a first electron source positioned proximate the first anode and configured to generate electrons that pass through the first anode and into the first ionization volume. The ions source assembly further includes a second anode defining a second ionization volume and a second electron source positioned proximate to the second anode and configured to generate to generate electrons that pass through the second anode and into the second ionization volume. At least one optical element is positioned proximate the first ionization volume and defines an aperture. The first and second anodes and the first and second ionization volumes are positioned along an ion optical axis of the mass spectrometer, and the first anode is positioned between the second anode and the aperture.

A mass spectrometer includes an ion source including: an ionization chamber including an ion ejection hole, and an electron introduction port and an electron discharge port; a repeller electrode; a filament; a trap electrode; and a magnetic field forming unit. A first distance in a direction along the ion optical axis between an end of the electron introduction port on an ion ejection hole side and an inner face of a wall of the ionization chamber in which the ion ejection hole is formed and/or a second distance in a direction along the ion optical axis between an end of the electron introduction port on a repeller electrode side and the repeller electrode, is set to be larger than a radius of gyration of the thermal electron estimated based on energy imparted to the thermal electron and intensity of the magnetic field formed by the magnetic field forming unit.