Preparation and humidity sensing properties of Fe-doped mesoporous silica SBA-15

Fe-doped mesoporous silica SBA-15 has been studied as a humidity sensing material. Comparing with pure SBA-15, Fe-doped SBA-15 shows improved humidity sensing properties within the relative humidity (RH) range of 11–95%. The impedance of our product changes by more than four orders of magnitude over the whole humidity range with the response time and recovery time are about 20 and 50 s, respectively. High selectivity and good stability are also observed based on our product. These results make Fe-doped SBA-15 a good candidate in fabricating humidity sensor.