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Self-cleaning materials have attracted immense commercial and academic interests in recent years. A major challenge is the scalable and cost-effective fabrication of three-dimensional bulk materials with remarkable self-cleaning and a desirable combination of tailored porosity, robust superhydrophobicity, excellent mechanical strength, heat insulation, and sound absorption ability. Here, self-cleaning concrete was achieved in one step through the combination of the liquid template pore formation and in situ bulk hydrophobic modification. The concrete exhibited superhydrophobicity with a high water contact angle of 166°both on the surface and inside of the sample, which qualified the sample with remarkable stain repellency and longterm stability. The water contact angle remained unchanged under continuous mechanical grinding and harsh environments, such as high temperature (450 °C in air and 650 °C in Ar) and chemical erosion. The concrete with a controllable porosity from 56.3 to 77.4% and homogeneous small pore size (∼15 μm) exhibited high compressive strength and low thermal conductivity. Furthermore, high sound absorption capacity (97%, 500 Hz) at a vibration frequency from 400 to 600 Hz was realized. With these excellent performances and characteristics and easy scalable fabrication, the concrete prepared in this work possessed a wide application prospect.

Silicon oxycarbide (SiOC) ceramics are attractive materials for anodes of lithium-ion batteries, because of their excellent structural stability and high rate capability. Nonetheless, complex production procedures hinder their commercialization. This work proposes a simple emulsion templating method using liquid poreforming agent to prepare hard SiOC microbeads, which feature spherical morphology (∼35 μm in diameter) and large specific surface area (217 m 2 g −1 ). Moreover, the produced SiOC microbeads have a hard and dense surface, which significantly improves the structural stability during the process of lithiation/delithiation. A discharge specific capacity of 805 mAh g −1 was reached after 300 cycles, using a current density of 360 mA g −1 , and 420 mAh g −1 was recorded after 1000 cycles, even at an ultrahigh current density of 3600 mA g −1 . The porous interior structure and the disordered carbon structure of the SiOC microbeads are contributory factors due to the fast mobility of Li + in the SiOC matrix, related to the coefficient of Li + diffusion (4.5 × 10 −6 cm 2 s −1 ) and eventually the rate capability of the material. Consequently, anodes of lithium-ion batteries with high performance can be produced via this fast and simple preparation method.

High desalination performance, dye retention, and antibacterial properties were achieved with a multifunctional thin-film nanocomposite (MTFN) membrane, fabricated by the incorporation of a novel nanocomposite structure of reduced graphene oxide@TiO2@Ag (rGO@TiO2@Ag) into the polyamide active layer. The specific characteristics of the graphene-based nanocomposite, synthesized by the microwave-assisted irradiation process, favored water channelization and provided superhydrophilicity and antibacterial properties to the MTFN membranes. In comparison with the conventional methods, such as multistep chemical process using strong agents for reduction and long-term energy-consuming hydrothermal process, microwave irradiation facilitated a green, fast, and cost-effective route for the fabrication of GO-based nanocomposites for multifunctional applications. Interfacial polymerization was performed on a polyethersulfone/Si3N4 robust hollow fiber substrate using m-phenylenediamine aqueous solution and 1,3,5-benzenetricarbonyltrichloride organic solution. The structural and chemical characteristics of the synthesized nanocomposites and the MTFN membranes were thoroughly studied by a series of characterization analyses (transmission electron microscopy, field emission scanning electron microscopy, X-ray diffraction, Fourier transform infrared, energy-dispersive X-ray spectroscopy, X-ray photoelectron spectroscopy, and atomic force microscopy). The physicochemical properties and the nanofiltration performance of the MTFN membranes were investigated after the incorporation of rGO@TiO2@Ag at various concentrations. The water contact angles confirmed the superb surface hydrophilicity of the MTFN membranes. High permeability (52 L·m–2·h–1), desalination (96% for 1 g/L Na2SO4 feed solution), and dye retention (98% for 0.5 g/L rose bengal feed solution) were recorded for MTFN enriched with 0.2 wt % rGO@TiO2@Ag. A 90% reduction in the number of viable bacteria (Escherichia coli), after 3 h of contact with MTFN membranes, confirmed the superior antibacterial activity of the produced membranes.

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