Study On The Synthesis And Properties Of Copper Doped Iron Carbide Electrode

The dye-sensitized solar cell?DSSC?as the third generation solar cells,have attracted much attention because of its environmentally friendly and cheap and other advantages,has become one of the alternative to traditional silicon solar cell selection.Generally speaking,DSSC is composed of a photo anode,a dye sensitizer,an electrolyte solution and a counter electrode.The function of the counter electrode is to collect the electrons in the external circuit and to catalyze the reduction of the electrolyte?I^-/I₃^-?.The traditional counter electrode material is precious metal platinum,because of its good catalytic performance,high conductivity and good chemical stability,but the price of platinum is very expensive,and the storage on the earth is limited,so it is very important to find a kind of counter electrode material which can substitute for platinum and has excellent catalytic performance.In this paper,a convenient method for the synthesis of iron carbide materials and successful incorporation of copper atoms,preparation of copper doped iron carbide materials with different copper atom doping amount,and to bulid copper doped iron carbide counter electrode,and the photoelectric properties were studied.Expect this new copper doped iron carbide materials to replace platinum as DSSC on counter electrode materials.The main research contents and conclusions are as follows:?1?Iron carbide material have been prepared by high temperature decomposition of 2-methyl imidazole and used as counter electrode material for dye-sensitized solar cells.The raw material used in the method is cheap and easy to obtain,and no pollution during the preparation process.Then study the DSSC with iron carbide counter electrode.The catalytic performance of the iron carbide counter electrode was mainly studied in DSSC.LSV,CV,EIS and other testing methods were used to analyze the factors affecting the catalytic performance of the counter electrode.The results showed that iron carbide counter electrode has good conductivity and catalytic property,the counter electrode/electrolyte interface resistance and ohmic resistance are relatively small,and the iodine ion can have a good diffusion channel,The DSSC on the photoelectric conversion efficiency of the iron carbide counter electrode is4.07%.From a cost perspective,iron carbide is a catalytic material used as counter electrode applied to the DSSC which can instead of platinum counter electrode.?2?Copper doped iron carbide material have been prepared by high temperature decomposition of 2-methyl imidazole and used as counter electrode material for dye-sensitized solar cells,which selects the correct amount of copper doped by experiment,Moore content of copper atoms decreased from 10%to 0.25%,to finally determine the molar content of copper atoms successfully doped into 0.25%,0.5%,0.75%,1%.Then the four kinds of Cu doped iron carbide counter electrode chemical and physical characterization.The results showed that because of the incorporation of copper atoms,the iron carbide crystal shrinkage,X ray diffraction peak shifts to the right;And so there are a certain number of Cu²⁺in iron carbide crystals,the presence of Cu²⁺will increase the conductivity of the whole material,the catalytic activity and better reversibility of electrode.When the amount of Cu is too small,the content of Cu²⁺is too small,and the performance of the electrode material is not much improved;But the concentration is too high,causes blocking and hinder iron carbide ion transfer,resulting in a decline in performance of electrode materials,Therefore,when the Cu content is appropriate,the performance of the electrode material is the best,that is,0.75%of the copper atom doping is the best.Finally,four kinds of copper doped iron carbide according to the doping amount of 0.25%,0.5%,0.75%,1%in DSSC and the photoelectric conversion efficiency is 4.45%,5.07%,5.68%,5.46%,respectively.?3?The photoelectric conversion efficiencies of four kinds of DSSCs with different copper doped iron carbide as counter electrodes are higher than the photoelectric conversion efficiency of DSSC with pure iron carbide as counter electrode,which explains that the incorporation of copper atoms that can improve the overall performance of iron carbide material.Compared with the DSSC photoelectric conversion efficiency of platinum counter electrode,the photoelectric conversion efficiency of DSSC with 0.75%copper doped iron carbide counter electrode is 91%of it.The raw materials for preparing iron carbide are cheaper than platinum,have more storage on the earth,therefore,also from a cost perspective,the copper doped iron carbide can be a substitute for platinum as a catalytic material for counter electrode in DSSC.