Mass spectrum chemical ionization source based on UV light emitting diode

The invention provides a mass spectrum chemical ionization source based on an UV light emitting diode. The mass spectrum chemical ionization source comprises the components of an UV light emitting diode, a photoelectron transmitting electrode, a photoelectron accelerating grid electrode, an ion repulsion electrode, a reagent ion leading-out electrode, a chemical ionization reaction zone electrode and a differential interface electrode, wherein the UV light emitting diode, the photoelectron transmitting electrode, the photoelectron accelerating grid electrode, the ion repulsion electrode, the reagent ion leading-out electrode, the chemical ionization reaction zone electrode and the differential interface electrode are arranged in an ionization source chamber. The ion repulsion electrode, the reagent ion leading-out electrode, the chemical ionization reaction zone electrode and the differential interface electrode are planar electrodes which are provided with through holes at central positions, wherein the chemical ionization reaction zone electrode is one planar electrode or more than one planar electrode which is separately, coaxially and parallelly arranged. The ion repulsion electrode, the reagent ion leading-out electrode, the chemical ionization reaction zone electrode and the differential interface electrode are separately, coaxially and parallelly arranged along the through hole axis of each electrode. The mass spectrum chemical ionization source is based on the photoelectric effect of ultraviolet light which is emitted from the UV light emitting diode. The generated photoelectron deionized reagent gas is utilized for realizing chemical ionization.