Superhydrophilic and Underwater Superoleophobic Poly(propylene) Nonwoven Coated with TiO₂ by Atomic Layer Deposition

Abstract

To develop an effective and convenient solution for underwater repelling oil and cleaning up oily water, TiO2 nano‐coating is deposited on the surface of poly(propylene) nonwoven (PPN) by atomic layer deposition (ALD). There is no evident change in the morphologies comparing ALD‐modified PPN with PPN except for thickness. For oils of different densities, such as 1,2‐dichloroethane, methylene chloride, chloroform, carbon tetrachloride, n‐hexane, and petroleum ether, the underwater oil contact angle and underwater oil sliding angle of ALD‐modified PPN range from 152.25° to 156.19° and 5.63° to 8.80°, respectively, exhibiting superior superhydrophilicity and underwater superoleophobicity. Notably, ALD‐modified PPN shows a high chemical stability in different solutions, such as acid, alkali, salt, and polar solvent, which even can slightly improve the underwater superoleophobicity of TiO2 nano‐coating. The excellent underwater anti‐oil property, self‐cleaning property, robust chemical resistance, and easily scaled‐up preparation process of TiO2‐coated PPN suggest great potential for practical applications in the energy, environmental protection, marine anti‐fouling, and microflow control fields.

The growth mechanisms of TiO2 film onto PET surfaces by atomic layer deposition

“…The C=O groups are most commonly found in the polymer subsurface. The interaction of the precursor and the carbonyl site can break hydrogen bonding, causing the polymer chain framework to open, allowing the precursor molecule to diffuse further into the subsurface region and affecting the smoothness of the coated surface [21,[36][37][38][39]. During the diffusion process, molecular weight at the near surface of the PET substrate may decrease because of the breaking of the polymer chains.…”

Antimicrobial TiO2 nanocomposite coatings for surfaces, dental and orthopaedic implants

“…Besides, TiO 2 NWs offer a high dielectric constant which enhances the electrostatic precipitation of the water droplets on the filter surface. The superhydrophilicity of TiO 2 NWs favours the adhesion and spread of the droplets, which could be attributed to the presence of several Ti 3+ sites on the surface [73] , [74] , [75] . Moisture or humid conditions are essential for the maximum ROSs generation under light illumination.…”