Fabrication And Property Research Of Nano Structure Arrays Boron Doped Diamond Electrodes

Boron doped diamond(BDD)electrodes are widely used in the field of water treatment because of its stable physical and chemical properties as well as excellent electrochemical properties.In order to improve the water treatment performance of BDD electrodes deposited on Ti substrate,this paper mainly conducts research on fabrication and property research of nano structure arrays BDD Electrodes based on double bias assisted hot filament chemical vapor deposition(HFCVD)system.The main work and research results of this paper are as follows:1.The experimental study of ultrasonic pretreatment after carbonization was carried out.SEM,Raman and EDS were used to characterize the coating quality,substrate morphology,coating surface and section morphology.Rockwell C indentation test and accelerated life test were used to test the adherence of the electrode.The results showed that boron-doped diamond electrodes with high quality and high adherence were successfully fabricated,and the service life is increased by 49.2% compared with the traditional pretreatment method.2.The electric field and voltammetric characteristics of double bias HFCVD were carried out.The study found that the electric field uniformity of samples surface was greatly improved by using a conductive rings(Size: 2 mm of ring width,0.5 mm of ring sample spacing).By studying the voltampere characteristics of double-biased HFCVD,it was found that the positive grid bias can assist in the establishment of the glow discharge process,which can also significantly increase the number and energy of ions.3.The preparation of nanostructured BDD electrode and the influence of etching parameters on the nanostructure were studied.Studies have shown that as the substrate bias increases,the etching effect gradually increases,and a cone array with a cone angle of about 70 ° and a cone height of 2.1 μm can be obtained at-250 V.As the bias continues to increase,the cone angle,cone height,and density of the cone decrease.As the etching time increases,the electrode surface tends to form smaller and sharper cone structures.With the increase of methane concentration,the physical sputtering effect is enhanced,and it will be easy to obtain a smaller and sharper cone structure.4.The electrochemical and water treatment properties of nanostructured electrodes were studied.Under different etching parameters,all the BDD electrode show a very high oxygen evolution potential,a very wide electrochemical window and a very low background current.When the etching parameters are: substrate bias-250 V,etching time 1 hour,methane concentration 2%,the effective electroactive surface area of this electrode is the largest,which is 31.0% larger than that of the unetched electrode.It was found that in the simulated wastewater treatment test,compared with the non etched electrode,the total water treatment efficiency of nanostructured electrode is increased by 24.3%,and the efficiency of the first 40 minutes is up to 55.0%.