Improve Indium Oxide Nanofibers Gas-sensing Performance By Doping

With the rapid development of science and technology, people enjoy plumpwealth today, but also suffering from the harm brought by environmental pollution.Among of pollutants, the gas emissions of pollutants attract more and more attentions.The waste gas which bring from combustion of coal, automobile exhaust emissions,contain large amounts of sulfur dioxide, carbon dioxide, nitrogen oxides, theseharmful gas emissions to our environment and poses a serious threat to health. So,how to monitor these harmful gases has become a very important problem in thefuture. Among of the sensors, the semiconductor sensor attract more and more eyeswith its excellent performance and low cost. In this letter, In₂O₃nanofibers wereprepared by an electrospinning method, and improve indium oxide nanometer fibersgas-sensing performance by doping.First of all, we doped Ni to the indium oxide nanometer fibers, in order toimprove the gas-sensing performance. Ni doped nanofibers were prepared by anelectrospinning method and characterized by differential thermal analyse （DTA）,thermal gravimetric analyse （TGA）, X-ray diffraction （XRD）, scanning electronmicroscopy （SEM）, X-ray photoelectron spectroscopy （XPS） and electron spinresonance （ESR）.Nanofibers after doped still has good appearance, andcharacterization results show that the doped nanofibers formed the solid solution.Thismaterial show good gas-sensing properties for nitrogen dioxide at low temperature,and Ni-doping improve their NO₂sensing performance greatly. In_2-xNi_xO₃nanofiberswith different molar ratios （4%,6%, and8%） of Ni was prepared in ourexperiment.In_2-xNi_xO₃sensor with6%Ni-doping In₂O₃nanofibers exhibits the highestresponse among all samples. The response to500ppb NO₂is7.2at a low operatingtemperature of90°C. Moreover, the sensor also exhibits excellent selectivity.Vanadium doped indium oxide nanofibers was also prepared in our experimentand Their sensing properties were also investigated in detail. V doped nanofibers wereprepared by an electrospinning method and characterized in the same way above. The results show that the doped nanofibers formed the solid solution, and Their sensingproperties to hydrogen sulfide is good. In_2-xV_xO₃nanofibers with different molarratios （4%,6%, and8%） of V was prepared in our article.6%Ni-doping In₂O₃nanofibers exhibits the highest response among all samples. The response to50ppmH2S is13.8at a low operating temperature of90°C. This materials can test the H2S ina complex environment due to their good selectivity.In this article, indium oxide nanofibers was prepared by an electrospinningmethod. We doped two different element to nanofibers in order to improve their gassensing properties. This article provides the basis of doping methods for experiment.