A comparison of chemical sensors based on the different ordered inverse opal films

The three different inverse opal films including polystyrene (PS), silicon dioxide (SiO2) and titanium dioxide (TiO2) inverse opal have been fabricated by the self-assembly colloidal crystal template technique. Based on the Bragg's law, these inverse opal films were used as chemical sensors chips to detect the different concentration of ethanol solutions. The optical sensing properties of three inverse opal films have been compared. The results indicated that the TiO2 inverse opal film is advantageous over the PS/SiO2 inverse opal films for detecting common organic solution. The TiO2 inverse opal film displayed a perfectly optical sensing properties and the sensitivity could reach to 10% difference ethanol concentration (upsilon/upsilon(0)). The chemical sensor based on the three-dimensionally macroporous inverse opal films could be applied in organic molecules detection when the high refractive index material is used as chip. (c) 2007 Elsevier B.V. All rights reserved.