Tree Ring‑Inspired Fibrous Helix for UV Shielding and Warning Based on Photo‑electricity‑Acoustic Energy Conversion

Flexible wearable ultraviolet(UV)shielding,monitoring and warning devices have important applications in civil and mili-tary fields.However,most flexible wearable UV devices show unsatisfactory performance due to their poor stability and easy failure at large strains.Herein,inspired by tree rings,we engineered a hierarchical composite nanofibrous helix with an alternately stacked Archimedes spiral structure via a cost-effective strategy.Based on a photo-electricity-acoustic energy conversion system,we fabricated an all-in-one device exhibiting strain-insensitive UV protection at 0–500%strain for UV shielding as well as strain-sensitive UV monitoring at 500–1500%strain for UV early warning.Compared with previously reported common nanofibrous membrane devices,the as-prepared composite nanofibrous helix shows great advantages in terms of stability and UV protection,especially at large strains.Furthermore,the helix demonstrates multiple functions of wear resistance,antibacterial properties,biodegradation and knittability.This versatile strategy holds great promise for wearable electronics and multifunctional devices.

Construction of superhydrophobic directly Z-scheme bismuth oxybromide/silver phosphate fabric surface with UV shielding and enhanced visible light absorption activity

Various forms of pollutants discharged from industrial and life;how to treat the opposite water-soluble pollutants at the same time is a challenge.Here,a superhydrophobic BiOBr/Ag3PO4 fabric(SH fabric)bulk material was prepared aiming at the diversity of pollutants.Water(WCA=160°)and oil contaminants(spread)have different wetting behavior on fabric surfaces.The high recovery efficiency for oil pollutants was achieved by using the selective oil removal property of the SH fabric.Meanwhile,the pollutants in the aqueous phase were removed by photocatalyst after oil/water separation.Mechanism analysis demonstrated that the direct Z-type heterojunction formed between BiOBr(EVB=1.66 eV;ECB=-1.08 eV)and Ag3PO4(EVB=3.03 eV;ECB=0.6 eV).It is worth noting that the SH fabric exhibited good mechanical stability and UV shielding performance,which have potential application in environmental control.

Synthesis and characterization of Sb-doped SnO_2-(CeO_2-TiO_2) composite thin films deposited on glass substrates for antistatic electricity and UV-shielding

Sb-doped SnO2(ATO)-(CeO2-TiO2) thin Films were deposited on glass substrates using the mixed solution including CeO2-TiO2 precursor and ATO particles by sol-gel dip coating process.ATO particles were prepared using low-temperature hydrothermal process.The mixed molar ratio of ATO to(CeO2-TiO2) vs the properties of CeO2-TiO2 thin film was investigated.The optical properties of the films were characterized by UV-visible transmission and infrared reflection spectra,the sheet resistance of ATO particles and films were measured by rubber sheeter(MYI-50) and four-point probe(HisuperGroup Inc,SDY-5),the surface morphology and structure of the films were analyzed using 3D Digitale Mikroskop and X-ray diffraction(XRD),respectively.The results showed that the ATO precursor solution lost weight completely at about 500 oC,and the ATO particles was obtained,which indicated the same rutile lattice structure as SnO2.The glass substrates coated with ATO-(CeO2-TiO2) thin films showed better properties in antistatic electricity(104-106 Ω/),shielding UV(almost 100%),visible light transmission(70%) and infrared reflection(】30%).

Fabrication and ultraviolet-shielding properties of silica-coated titania-doped ceria nanoparticles

A series of well-dispersed titania-doped ceria nanoparticles Ce1–xTixO2 were rapidly prepared by a novel salt-assisted solution combustion process using correspondent metal nitrates as oxidizers and ethyl glycol as fuel, and then coated with amorphous silica by seeded polymerization using tetraethyl orthoslicate （TEOS）. The as-prepared samples were characterized by transmission electron microscopy （TEM）, X-ray diffraction （XRD）, Fourier-transform infrared spectroscopy （FTIR）, and ultraviolet-visible light （UV-Vis） diffuse reflectance spectroscopy. The results indicated that compared with the as-prepared pure ceria nanoparticles, the red-shift phenomenon occurred for Ti-doped ceria nanoparticles with Ti incorporation. Meanwhile, the absorption intensity in the UV light region slightly decreased and transmission rate in visible light region was somewhat enhanced. In comparison with the silica-coated CeO2 nanopowders, the silica-coated Ce0.95Ti0.05O2 nanopowders displayed the same absorption intensity in the UV light region, broader UV absorption band and higher transmission rate in visible light region.

Carbon dots enhanced gelatin/chitosan bio-nanocomposite packaging film for perishable foods

Carbon dots(CDs)with intriguing fluorescent property,good biocompatibility,high stability,easy interaction with substrates,are burgeoning carbon nanoparticles with large potential in various applications.Incorporating CDs into the polymer matrix is becoming a popular strategy to endow the complex with new functions.Herein,the green-synthesized CDs was integrated into the mixture of gelatin(derived from waste fish scale)and chitosan,and a multifunctional bio-nanocomposite(defined as Gelatin/Chitosan/CDs)film was developed,which showed the excellent antibacterial,antioxidant,pH-sensitivity,UV shielding,and blue-emission properties.The effects of different concentrations of CDs on the physical,mechanical,structural,and functional activity of bio-nanocomposite film were tested.Compared with the Gelatin/Chitosan film,the Gelatin/Chitosan/CDs film with an optimum addition of 20%CDs showed the enhanced antibacterial,antioxidant as well as UV shielding activities.More importantly,it was used as an effective packaging material for fish meat preservation,reducing the loss of nutritional quality consumption,extending the shelf life of food.Besides,the bio-nanocomposite films also possessed the anti-counterfeiting and pH-responsive properties due to the strong fluorescent emission of CDs,and had the great potential in developing the intelligent packaging materials.Our work shed new light on the new application of CDs and the synthesis of bio-nanocomposite film in food industry.