Humidity sensitive property of Li-doped 3D periodic mesoporous silica SBA-16

Li-doped 3D periodic mesoporous silica SBA-16 has been successfully prepared and investigated as humidity sensor material. After doping of 10% (wt) lithium chloride, mesoporous silica SBA-16 showed significant change in impedance of more than three orders of magnitude over almost the whole humidity range (11–95%RH), with fast response time (about 25 s), and relatively low hysteresis (about 4%). The comprehensive affections of the 3D mesoporous structure, highly dispersed uniform morphology, hydrophilic behavior of triblock copolymer surfactant F108, and the doped Li+ maybe make a great contribution to the improvement in the humidity sensitive property. A possible mechanism was also provided to explain the humidity sensitive properties.