A preparation method of a pt disk submicron electrode with controllable geometry

Abstract

The invention discloses a preparation method for a Pt disk sub-micron electrode with a controllable geometrical shape. The method mainly comprises the steps of placing a Pt wire in a capillary glass tube; thinning a middle part of the capillary glass tube through adoption of a laser drawing device; enabling the capillary glass tube to fit with the Pt wire completely; breaking the capillary glass tube to obtain ultramicro electrodes; heating the tips of the ultramicro electrodes through adoption of a needle grinding device; controlling the diameters of the capillary glass tubes and electrode RG by controlling the heating process; and cutting off the sections of the tips of the ultramicro electrodes through adoption of a focused ion beam electron microscope, thereby obtaining the Pt disk sub-micron electrodes. According to the method, the obtained Pt sub-micron electrodes are flat in end face, uniform and densified in insulation layer, high in sensitivity and excellent in electrochemical performance and are especially applicable to basic electrochemistry and bioelectrochemistry sensors and scanning probes.

Description

technical field [0001] The invention relates to a preparation method of a Pt disc submicron electrode with controllable geometry, and the Pt disc submicron electrode can be widely used in electrochemical basic kinetics, bioelectrochemistry and electrocatalysis, and ultra-high resolution scanning electrochemistry Microscopy (High Solution Scanning Electrochemical Microscopy, HS-SECM) research. Background technique [0002] Compared with the traditional macroscopic electrodes (generally considered to be more than 1 mm in size), ultramicro electrodes with a size of less than 25 microns have a smaller time constant and are easier to reach a steady state because of their different diffusion methods from the larger electrodes. Therefore, ultramicroelectrode electrochemistry is an important direction in the development of electrochemical research in the past 30 years. Compared with spherical, strip-shaped or columnar ultramicroelectrodes, disc ultramicroelectrodes are relatively e...

AI Technical Summary

Problems solved by technology

[0003] (1) It is difficult to prepare Pt ultramicroelectrodes smaller than 5 microns, especially submicron electrodes smaller than 1 micron. The glass diameter of the electrode tip is usually greater than 30 microns, and the tip of commercial Pt ultramicro electrodes even reaches 100 microns;

[0004] (2) The surface roughness of the electrode obtained by mechanical or manual polishing is relatively large, and gaps are easily generated between the glass and the Pt wire, and the end surface of the Pt wire is not horizontal enough, and the geometric shape is not regular enough, so it is easy to find different degrees of inclination;

[0005] (3) The repeatability is relatively poor, especially the control of RG, and the human factors increase

[0007] (1) The size of the electrode is difficult to control. Because the ultra-micro electrode used directly is broken by laser melting, the surface of the electrode is very uneven, and sometimes even part of the glass is coated on the end surface of the Pt wire;

[0008] (2) The controllability of RG is poor, and the controllability of the tip morphology and geometry of the micro-nano electrode is poor by mechanical grinding or manual;

[0009] (3) Due to mechanical or manual grinding, it is easy to generate a gap between the electrode and the glass seal

Images