A composite scanning microprobe with double electrodes and its preparation method

Abstract

The invention discloses a composite type scanning microprobe with dual electrodes. The composite type scanning microprobe comprises a platinum filament microelectrode, a tungsten filament microelectrode and a glass tube with two inner holes. The platinum filament microelectrode and the tungsten filament microelectrode are arranged in the two inner holes of the glass tube respectively, and the lower portions of the two inner holes of the glass tube are at least respectively filled with epoxy resin to fix the platinum filament microelectrode and the tungsten filament microelectrode. After the epoxy resin is solidified, the lower end of the glass tube is ground to be in a cone shape, sharp ends are formed at the lower end of the platinum filament microelectrode and the lower end of the tungsten filament microelectrode and are exposed to the outside, and the lower end of the platinum filament microelectrode is placed at the conical sharp end of the lower end of the glass tube. WO3 is formed at the lower end of the tungsten filament microelectrode in an oxidation mode, a W / WO3 microelectrode is formed, and the upper end of the platinum filament microelectrode and the upper end of the tungsten filament microelectrode are respectively and electrically connected with a wire. The glass tube is further sleeved with a stainless steel tube. The invention further discloses a preparation method of the composite type scanning microprobe. According to the composite type scanning microprobe with the dual electrodes and the preparation method thereof, STM images and pH value distribution can be measured on a metal surface at the same time, and the resolution ratio and the detection efficiency are high.

Description

technical field [0001] The invention relates to a microprobe used for a scanning tunneling microscope (STM), in particular to a composite scanning microprobe with double electrodes capable of simultaneously measuring STM images and pH value distribution on a metal surface and a preparation method thereof. Background technique [0002] Scanning tunneling microscope is abbreviated as STM. As a scanning probe microscopy tool, the scanning tunneling microscope allows scientists to observe and locate individual atoms at a much higher resolution than its atomic force microscope counterpart. The performance of the microprobe used in the scanning tunneling microscope determines the performance of the scanning tunneling microscope. [0003] When the scanning microelectrode measurement (SMET) system assisted by scanning tunneling microscope (STM) is used to study the localized corrosion of metals, since the pH value of the environmental medium is one of the most important factors aff...

AI Technical Summary

Problems solved by technology

Traditional glass pH electrodes usually use a relatively thin glass membrane as a sensitive membrane for hydrogen ions, which is easily broken; moreover, glass electrodes are bulky, costly, and difficult to miniaturize. Generally, they can only measure the average pH in a large number of solution systems value, unable to meet the requirements of in-situ measurement of pH value with micron spatial resolution at the metal / solution interface

In addition, this traditional glass pH electrode cannot measure the STM image of the metal surface at the same time.

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