Preparation of CdS/PU nanocomposite films by simulating bio-mineralization process and its sensing properties for Ag(I) ions

A pollution-free method to synthesize polyurethane (PU) was used. PU/CdS nanocomposite films were synthesized by simulating bio-mineralization process. The factors that affect the hydrothermal stability and fluorescence properties of the films were studied. Further, the sensing properties of the nanocomposite films to Ag(I) ions in water were systematically investigated. A scanning electron microscopy observation showed that the sizes of the CdS particles are around 60 nm, and the particles are evenly doped within the PU films. The fluorescence emission of nanocomposite films has been found to be very sensitive to the presence of Ag(I) ions, and a small amount of Ag(I) ions makes the emissions increase dramatically. The emission is hardly affected by other common ions in water except chloride and sulfate through their precipitation effects on Ag+ ions. The films are predicted to have the potential to be developed into excellent sensing films for Ag(I) ions in water.