Solar-driven interfacial evaporation (SIE) is emerging as an energy-efficient technology to alleviate the global water shortages. However, there is a fatal disadvantage in using SIE, that is, the volatile organic compounds (VOCs) widely present in feedwater would concurrently evaporate and transport in distilled water, which threatens the water safety. Photocatalysis is a sustainable technology for pollution control, and after years of development, it has become a mature method. Considering the restriction by the insufficient reaction of the permeating VOCs on the two-dimensional (2D) light-available interface of conventional materials, a 3D photocatalytic approach can be established to boost VOC rejection for photothermal evaporation. In the present work, a light-permeable solar evaporator with 3D photocatalytic sites is constructed by a porous sponge decorated with BiOBrI nanosheets with oxygen-rich vacancies. The 3D microchannels in the evaporator provide a light-permeable path with the deepest irradiation depth of about 580 μm, and the reactive interface is increased by tens of times compared with the traditional 2D membrane, resulting in suppression of VOC remnants in distilled water by around four orders of magnitude. When evaporating river water containing 5 mg L–1 extra added phenol, no phenol residues (below 0.001 mg/L) were detected in the produced freshwater. This development is believed to provide a powerful strategy to resolve the VOC bottleneck of SIE.

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Photothermal sterilization based on PBNs has been demonstrated not only upon NIR irradiation but also most importantly under simulated solar light.

Ammonium recovery from wastewater by gas-permeable membranes is promising but suffers from the tradeoff between membrane stability and permeability under harsh operating conditions. Chemical-resistant membranes display modest permeability due to the poor solubility and processibility; chemically active membranes are easier to be endowed with better permeability however hinder by instability. To resolve such a problem, we cleverly design a novel membrane configuration via one-step solution-electrospinning, with the chemical-active component (low-strength fluorine polymer) as the inner skeleton to construct interconnected porous structures and the chemical-resistant component (high-strength fluorine polymer) as the outer armor to serve as a protective layer. Due to the significantly enhanced mass transfer coefficient, the interconnected-porous armor-structured membrane exhibited much higher permeability for NH4 +-N recovery, which was 1.4 and 5 times that of the traditional PTFE membrane and PP membrane, respectively. Through long-term intermittent and consecutive experiments, the reusability and durability of the armor-structured nanofibrous membrane were verified. When treating actual hoggery wastewater with complicated water quality, the armor-structured nanofibrous membrane also displayed robust stable performance with excellent antiwettability. The mechanisms of membrane formation, corrosion resistance, and mass transfer were discussed in detail.

Bioceramic calcium phosphorus (CaP) coatings were prepared on self-designed Mg–xZn–0.6Ca (x = 3.0, 4.5, 6.0 wt. %) alloy by microarc oxidation (MAO). The corrosion resistance, bioactivity, and biodegradability of the CaP coatings prepared on alloys with different zinc (Zn) contents were systematically studied and discussed by potentiodynamic polarization and in vitro immersion tests in the simulated body fluid solution. The CaP coatings and corrosion products were characterized by scanning electron microscopy, energy dispersive spectrometry, x-ray diffraction, and Fourier transform infrared spectroscopy. Based on the difference of microstructure caused by zinc content, the effect of microstructure on the properties of MAO coatings was analyzed by taking grain boundary and second phase defects as examples. Results showed that the CaP coatings could be prepared on the surface of the self-designed Mg–Zn–0.6Ca alloy by MAO. The CaP coatings have good bioactivity. Meanwhile, the Zn content has a significant effect on the microstructure of the CaP coatings. When the Zn content is 3.0 wt. %, the corrosion resistance and biocompatibility of the CaP coatings are obviously improved with good biological properties.