Preparation Of Iron Doped Zirconia Nanofibers By Electrospinning And Their Gas Sensing Properties

The development of a gas-sensitive sensing material that can effectively detect specific gases in harsh environments is not only of great scientific research significance,but also has practical application value for improving human health,eliminating potential safety hazards,and controlling environmental pollution.This article comprehensively considers the practical application scenarios of gas-sensitive sensing materials,selects ZrO2 as the base material,and uses Fe element to dope.Fe-ZrO2 nanofibers are prepared by electrospinning technology.TG-DDSC,SEM,EDS,XRD,XPS,In-Situ-FTIR and other detection methods analyze and characterize the material's thermal weight loss process,phase transition process,micromorphology,element distribution,crystal structure and gas adsorption process.At the same time,electrochemical workstation was used to test the electrochemical performance of the material.Research indicates:(1)10 mol%Fe-ZrO2 nanofibers undergo decomposition of PVP main chain and ZrOCl2,Fe(NO3)3 at 295 ?,and undergo phase transformation at 423? to form cubic crystals;nanofibers with an average diameter of 135.7 nm were obtained after calcination,and Fe element was completely dissolved in ZrO2 to form a solid solution.Fe-ZrO2 has N-type semiconductor characteristics.Under N2 atmosphere,it has the highest sensitivity to SO2,reaching 2.15,the response time is relatively slow,and it does not recover after the gas is removed.At the same time,the response to SO2 concentration changes is not significant.The average response time to H2 and CO was 20.4 and 19.4 s,and the average recovery time was 90.5 and 199.4 s,respectively,and there was a linear relationship with the changes in H2 and CO concentrations.In the air atmosphere,the sensitivity to reducing gas was very weak.(2)The optimal calcination temperature of Fe-ZrO2 is 600?;in samples with different Fe doping amounts,surface of nanofibers of 35 mol%Fe-ZrO2 is smooth and without breakage after calcined at 600?;it shows a cubic phase and interstitial solid solution characteristics.35 mol%Fe-ZrO2 nanofibers have excellent gas-sensitivity properties,among CO,CH4 and H2 three gases,it has good selectivity and stability for H2.The highest sensitivity value appears at 240? and the recovery time is short after the gas is evacuated,so the optimal Fe doping amount for Fe-ZrO2 is 35 mol%.(3)After calcination at 600?,pure ZrO2 is monoclinic,8YSZ and 35 mol%Fe=8YSZ are cubic phases;pure ZrO2 has the highest sensitivity to H2 at 580?,and the sensitivity of 35 mol%Fe-8YSZ to H2 is greater than 8YSZ,but the sensitivity of these three materials to H2 is much lower than 35 mol%Fe-ZrO2,so Fe-ZrO2 has the potential to become a high-performance H2 gas sensing material.