The Electrostatic Spinning Preparation Of ZnO And ZnFe₂O₄ And Gas Sensor Performance

With the development of industry,increasingly serious air pollution resulted in a harmful impact on the environment.Especially in recent years,our country,haze is particularly serious.To quickly and accurately detect these toxic gases is essential,Therefore,to design gas sensors with low operation temperature,high selectivity and fast response is necessary.However the operation temperature of conventional semiconductor gas sensor is high,also selectivity and response is not satisfactory.This paper explores the electrospinning preparation of ZnO nanomaterial and application in gas sensor,In addition,we prepared ZnO/ZnFe₂O₄ nanocomposite.1.Preparation of ZnO nanomaterialsZno nanomaterial was successfully prepared by electrospinning.Scanning electron microscope showed the average diameter of the product was about 200nm.XRD patterns verified the crystalstructure of product.2.Preparation ZnO/ZnFe₂O₄ NanocompositeWith mixed Zn?CH₃COO?₂·2H₂O,Fe?NO₃?₃·9H₂O and PVA to obtain electrospinning precursor,Under voltage of 18KV,the diameter of product is about500nm.Next,the product was annealed?300?3 hours 500?3 hours 700?5 hours?to prepare ZnO/ZnFe₂O₄ nanomaterials.3.ZnO and ZnO/ZnFe₂O₄ nanomaterials gas sensing propertiesFirstly,gas sensing properties of ZnO materials were tested in ethanol,acetone and hydrogen sulfide gas.The optimum operation temperature in ethanol is 250?,andthe same concentration of the acetone and hydrogen sulfide were also tested,Under the voltage of 2.5V,the response of ZnO to hydrogen sulfide is maximum.To summary,ZnO is a good gas-sensitive materials.Secondly ZnO/ZnFe₂O₄ nanomaterials were also test in ethanol,acetone and hydrogen sulfide gas,Found with respect to gas,ZnO/ZnFe₂O₄ nanocomposite has better response to H₂S than ethanol and acetone.Compared to ZnO materials,gas sensing properties of ZnO/ZnFe₂O₄ were improved.Furthermore,long-term stability of the material was tested.