Low temperature sputtered TiO2 nano sheaths on electrospun PES fibers as high porosity photoactive material

We propose a low temperature approach based on combining an electrospinning methodology and reactive sputtering processes to realise a porous mesh of polyethersulfone (PES) fibers (similar to 700 nm in diameter) wrapped by TiO2 nano-sheaths, active under UV illumination. The mesh has a porosity as high as similar to 91% in volume and was prepared at T <= 160 degrees C. The effectiveness of the TiO2/PES mesh under UV was proved by Methylene Blue (MB) dissociation experiments and related to the TiO2 coverage properties, namely its thickness (similar to 15 nm), its nano-structuring (grains diameter 8-10 nm) and lattice structure (anatase) that improve the photo-activity action. The combination of electro-spinning plus sputtering processes lays the basis for high porosity and low cost, high throughput, high yield and flexible purifying filter technologies.