Superhydrophobic surfaces have great potential for self-cleaning, anti-icing, and drag-reducing characteristics because of their water repellent property. This study demonstrates the potential application of coatings to protect architectures from detrimental atmospheric effects via a self-cleaning approach. In this research, a SiO₂-TiO₂-PDMS composite coating was prepared on the surface of building walls by the sol-gel method. Tetraethyl orthosilicate (TEOS) and titanium isopropoxide (TTIP) were used as inorganic precursors, and polydimethylsiloxane (PDMS) was used as low surface energy substances. The effects of TEOS and PDMS content on microstructure, wettability, and self-cleaning performance of coating wall surfaces were investigated by conducting various tests, including scanning electron microscopy (SEM), X-ray energy spectroscopy (EDS), angle measurement, and Fourier transform infrared spectroscopy (FTIR). The results indicated that hydrolysis and condensation reactions of TEOS, TTIP, and PDMS were performed on the surface of the substrates, leading to a micro- and nano-structure similar to the surface of lotus leaves. When the molar ratio of PDMS to TEOS was 1:5, the static contact angle of the coating reached a maximum of 152.6°. At this point, the coated surface was able to resist the adhesion of particle pollutants and liquid pollutants, which could keep the walls clean and possess a good ability of self-cleaning. In conclusion, SiO₂-TiO₂-PDMS composite coating is potentially useful in wall protection applications with its hydrophobic and environmentally friendly superhydrophobic properties.

Porous Nb-25Ta-25Ti alloys (60% porosity and 100–600 μm pore size) for bone implant applications were manufactured combining impregnation and sintering methods. Surfaces with porous micro-nanostructured networks on Nb-Ta-Ti alloys were successfully modified by various surface pre-treatments (acid etching, alkali-heat treatment and annealing treatment). Surface characteristics and Ca-P layer deposition behaviors of the multilevel structured porous Nb-Ta-Ti alloys were investigated by conducting various tests, including x-ray diffraction, scanning electron microscopy, energy-dispersive x-ray, atomic force microscopy and optical contact angle measurement. In particular, bulk Nb-Ta-Ti alloys were also used as mutual control. The results demonstrated that the porous alloy exhibited a unique multilevel porous structure with macro-networks and micro-pits after pre-treatments. The surface passive TiO ₂ /Nb ₂ O ₅ /Ta ₂ O ₅ layers on Nb-Ta-Ti alloys were partially dissolved by the corrosive attack of hydroxyl ions during alkali heat treatment. In addition, subsequent annealing treatment increased the density of the gel layers formed during alkali heat treatment. After immersion in SBF for 14 d, a continuous relatively uniform apatite layer was formed on the multilevel structured surfaces. Moreover, the mechanism of surface mineralization can be construed as electrostatic interactions between substrates and ions. Furthermore, in vitro cell culture showed that Nb-Ta-Ti alloys had a good biocompatibility and the multilevel porous structure could enhance the cellular behaviors including: cell adhesion and spreading.

Fair-faced concrete can be applied as conventional structural materials but also as exterior wall materials due to its remarkable decoration performance. However, the wide applications of fair-faced concrete are limited due to its low workability and complex appearance quality process. In the present work, C40 concrete was prepared based on the fabrication theory of fair-faced concrete and self-compacting concrete, and materials design and appearance quality control methods were systematically analyzed. The results showed that the surface porosity ratio was only 1.37% when the content of the defoamer was 0.1%, and the ratio of hole area was only 1.8% with a combination of wooden molds and water-based release agents. Moreover, the color difference value could be controlled below 3.0 due to its inapparent color difference for human eyes.

In order to enhance the interfacial bonding between steel fibers and cement-based materials, a modified solution was prepared by 3-aminopropyltriethoxysilane (KH-550) and tetraethyl orthosilicate (TEOS) using the sol-gel method. The effect of relative concentration of KH-550 on pullout properties and microstructure of surface coating was studied. Moreover, corrosion resistance in three kinds of solutions (NaCl, Na 2 SO 4 , and HCl) of modified steel fibers was also discussed. The results showed that the effectiveness of silane coupling agents in modifying the surface of steel fibers was influenced by the relative concentration of KH-550. When the relative concentration of KH-550 was low, the adhesion of the coating to steel fiber surface was poor. Conversely, excessively high concentrations increased coating thickness but make it prone to cracking. When the KH-550/TEOS ratio was 3, the surface coating exhibited high smoothness, minimal cracks, and excellent adhesion. In addition, the ultimate pullout load, pullout energy consumption, and bond strength of modified steel fibers all reached more than 170% compared to that of untreated samples. In corrosive environments, the mass loss rate and the performance in pullout tests of modified steel fibers showed far smaller reductions compared to untreated steel fibers. Moreover, the difference in corrosion resistance became more pronounced over time due to the interfacial bonding and effective physical barrier provided by the modification.