Fluorescence properties of nonconductive organic small molecule nano-films prepared by DC sputtering method

The key to preparing nano-films by DC (Direct Current) sputtering is to prepare the film materials into targets. Organic small molecule fluorescent materials (such as 1, 4-Bis(2-cyanostyryl) benzene, to be noted as ER-I) are usually not conductive, and it is not possible to make the elements as targets. Therefore, there are some difficulties in preparing the organic materials into films by DC sputtering. In this paper, we fabricated ER-I nano-films by using the DC sputtering method, and their fluorescence properties are significantly different from those of powder materials. The fluorescence emission spectra of the films prepared by the DC sputtering method have an apparent bimodal morphology. Compared with the ER-I powder material, the fluorescence emission peak has a blue shift of 5 nm and 22 nm. To study the luminescence mechanism of the films, we further investigated the fluorescence properties of the films after thermal treatment and analyzed the structure and surface morphology of the films by XRD and SEM. This paper provides a new idea and method for the preparation of organic nano-films and has a potential application value in the preparation of organic light-emitting films and soft optics devices.