Behavioral experimental studies of a novel vapochromic material towards development of optical fiber organic compounds sensor

A new vapochromic material of formula [Au(PPh₂C(CSSAuC₆F₅) PPh₂Me)₂][ClO₄] has been developed and used for the detection of some volatile organic compounds (acetone, dichloromethane, chloroform, etc.). The material is presented in the form of powders which color changes with organic compound vapors turning from black when there is no vapor to orange when there is vapor. By using the sol-gel technique, the powder - dispersed in tetraethyl orthosilicate - was easily deposited on optical fibers. In order to study experimentally the behavior of the material for fabricating practical optical fiber sensors, a sol-gel material doped with vapochromic material is deposited onto an extreme of a monomode fiber connected to a coupler. The behavior of the material was studied for different wavelengths and concentrations of volatile organic compound vapors. Changes up to 10 dB in the reflected optical power were detected.