Oca15 machine

The microstructure of the as-prepared TiO₂ nanoparticles was characterized by high-resolution transmission electron microscopy (HR-TEM, JEM 2100F, JEOL, Japan) and atomic force microscope (AFM, SPM-9600 series, Shimadzu, Japan). The surface morphology of the membranes was recorded by field mission scanning electron microscope (FESEM, SU-8010, Hitachi Limited, Japan). The chemical composition of the samples was determined with the means of X-ray diffraction spectroscopy (XRD, Bruker D8 Advance, Bruker-AXS, Germany), XPS (PHI Quantera SXM, ULVAC-PHI, Japan), and Fourier transform infrared spectroscopy (FTIR, V70, Bruker, Germany). The fluorescence spectra were measured by a fluorescent photometer (RF-2000, SHIMADZU, Japan). Confocal images were collected by a laser confocal microscopic system (LSM-780, Zeiss, Germany). A PerkinElmer Lambda 750 UV spectrometer (United Kingdom) was used to test the phenol concentration. The contact angles were probed with a contact angle measurement machine (OCA 15 machine, Data-Physics, Germany). Moreover, the final contact angle of each sample was calculated by measuring three contact angles of different positions and taking the average. In the liquid dropping tests, the motion of the test droplets was captured with the help of a digital still high-speed camera (FASTCAM SA-Z, PHOTRON, Japan) of 10,000 fps.