Abstract: The four-dimensional microscope includes a sample plate, a laser device, an aperture, an extraction plate, a hexapole, a quadrupole, a time-of-flight mass analyzer, a detector, and a device for supplying a voltage to the sample plate, the aperture, the extraction plate and the hexapole and the quadrupole. By utilizing the tunneling effect of photo-induced electrons on surfaces of semiconductor materials under laser irradiation and the electron capture ionization, mass-to-charge ratios and signal intensities of the ions resulting from the capture of interfacially transferred photo-induced electrons and subsequent photo-chemical reactions are measured, and image reconstruction is performed to obtain microscopic images. By using the present invention, not only active photo-catalytic sites of the semiconductor materials are imaged but also various structures of intermediates and products of photo-chemical reactions can be determined.

Abstract: A mass calibration kit and a calibration method for a low-mass area of a high-resolution mass spectrometer in negative ion mode. The mass calibration kit comprises semiconductor nanometer material suspension, a free fatty acid standard solution and a MALDI sample target cleaning liquid. The mass calibration method comprises: adjusting a voltage difference between a sample target of the mass spectrometer and a slit to be 20 V; dripping the semiconductor nanometer material suspension on the surface of the sample target till a solvent is completely volatilized and dried; dripping the free fatty acid standard solution on the surface of a semiconductor nanometer material till the solvent is completely volatilized and dried; and putting the sample target in the mass spectrometer for mass calibration, wherein calibration coefficients obtained after the instrument calibration can be used for correcting a sample mass spectrometric detection result.

Abstract: A mass calibration kit and a calibration method for a low-mass area of a high-resolution mass spectrometer in negative ion mode. The mass calibration kit comprises semiconductor nanometer material suspension, a free fatty acid standard solution and a MALDI sample target cleaning liquid. The mass calibration method comprises: adjusting a voltage difference between a sample target of the mass spectrometer and a slit to be 20 V; dripping the semiconductor nanometer material suspension on the surface of the sample target till a solvent is completely volatilized and dried; dripping the free fatty acid standard solution on the surface of a semiconductor nanometer material till the solvent is completely volatilized and dried; and putting the sample target in the mass spectrometer for mass calibration, wherein calibration coefficients obtained after the instrument calibration can be used for correcting a sample mass spectrometric detection result.

Abstract: An image acquisition semiconductor film for a high-resolution mass spectrometric imaging system, and a preparation method and an application. The image acquisition semiconductor film for the high-resolution mass spectrometric imaging system is prepared by using the following method: weighing semiconductor nanometer particles, putting the semiconductor nanometer particles into a muffle furnace for burning first, further grinding by using an agate mortar, and uniformly dispersing the semiconductor nanometer particles so as to obtain semiconductor nanometer powder; and finally, pressing the semiconductor nanometer powder in a compressor so as to obtain the semiconductor film.