Fabrication of micro-structures on a PVDF/TiO2 nano-composite film using photocatalytic lithography

In the present study, a poly(vinylidene fluoride) (PVDF)/TiO2 nano-composite film was prepared by coating a substrate with an acetone/DMF solution, which was then evaporated at a temperature of 110 °C. Micro-structure patterns were fabricated on a PVDF/TiO2 nano-composite film with photocatalytic lithography. The morphological and chemical compositions of the micro-structure were investigated by optical microscope, SEM and XPS. Experimental results show that the micro-structure patterns can be directly replicated on the PVDF/TiO2 nano-composite film with photocatalytic lithography. The micro-structure is approximately 4 μm in depth which is obtained during the water phase of the process with UV-LED irradiation in 5 h. The results indicate that the fabrication methodology can be potentially applied towards the large-scale fabrication of actuators and sensor devices.

As a photocatalyst, TiO2 can induce degradation of PVDF via UV irradiation. To further promote the degradation of PVDF and form the three-dimensional micro-structure, deionised water was continuously cycling in the gap between the mask and film.Highlights► Micro-structures were replicated on a PVDF/TiO2 film with photocatalytic lithography. ► Micro-structure patterns were obtained via water phase process with UV irradiation. ► PVDF defluorination occurs in the micro-structure grooves.