Preparation of composite Langmuir-Blodgett films based on carbon spheres and wide applications for acid/alkaline gas sensor, surface enhanced Raman scattering and photoelectrics

Through this study, a variety of carbon spheres/dye (CS/dye) composite films were prepared based on the Langmuir-Blodgett (LB) technology. The prepared CS/dye composite films were tested for acid and alkali gases discoloration characteristics. The CS/CR composite film shows good acid/alkaline gas sensing performances, and its characteristic absorption peaks have a significant movement in the UV–vis spectrum. In addition, the surface enhancement of the Raman scattering (SERS) experiment proves the good Raman enhancement performance of the prepared composite LB film with the enhanced factor (EF) of 8.5 × $\times$ 10 4 . The relative standard deviation of Raman intensity is 24.74 %, indicating the good reproducibility and uniformity of composite film, which makes it applicable to the detection of trace molecules. Furthermore, the CS/NR composite film has a current density of 1217 μA/cm 2 when the potential voltage is 1 V, indicating that the composite film has a high carrier transfer rate, which provides a reference for further exploration of optoelectronic devices of CSs system.