Search

High-entropy alloys (HEAs), which are defined as near-equimolar alloys of five or more elements, are attracting ever increasing attention because of the unique properties in a variety of applicatio...

Photosensitizers with charge-separated excited states are commonly introduced into photocatalytic systems to accomplish photon-to-electron transformation. Unfortunately, the photosensitizers in cur...

It is a challenge to fabricate three-dimensional carbon aerogels based on natural renewable resources with stability, flexibility, and versatility. Here, an ultralight, elastic, and hydrophobic mul...

A novel nanospherical hydrous titanium oxide adsorbent (hydrous titanium oxide-immobilized bovine serum albumin nanospheres, HTO-BSA-NSs) was prepared by immobilizing HTOs with a manipulated molecular mass and number of active sites for uranium on the surface of BSA-NSs. The adsorption performances of HTO-BSA-NSs were investigated in spiked natural seawater with extra 8 ppm uranium. The results demonstrated that HTO-BSA-NSs are capable of uranium capture from a complex aqueous matrix with a low uranium concentration. Meanwhile, the microbial stability of HTO-BSA-NSs in sterilized natural seawater with Marinobacter sp. was investigated and observed through an optical microscope and TEM, revealing that the wrapped HTOs could protect the BSA-NSs from the decomposition of microorganisms, and the structure and functional groups of HTO-BSA-NSs remain stable compared with the BSA-NSs. In addition, the uranium adsorption mechanism of HTO-BSA-NSs is mainly recognized as dehydrated complexation, which was concluded from characterization analysis, adsorption model fitting, and theoretical calculations based on density functional theory. The remarkable uranium adsorption performance and microbial stability of HTO-BSA-NSs indicated that they have the potential to be a low-cost and environmentally friendly adsorbent for uranium extraction from complex environments such as seawater or uranium-containing industrial wastewater.

This research investigated the emission and evolution characteristics of fuel-N during the O2/H2O combustion process of a typical bituminous coal (Shenhua). To avoid the catalytic interference of alkali metal salts, the demineralized coal obtained from the raw coal sample was employed for the investigation in this research. The effects of reaction temperature (Tr) and H2O concentration, which were two vital factors affecting coal combustion characteristics, on the emission characteristics of fuel-N during the combustion process were also taken into consideration. Isothermal combustion tests performed under different O2/H2O conditions (Tr: 1073 and 1473 K; O2: 30%; H2O: 0, 3.5, 8.5, 15, 20, and 30 vol %) indicated that relatively high concentrations of N2O, HCN, and NH3 were measured in the O2/H2O combustion of the coal sample. With the increase of Tr and H2O concentration, more fuel-N would be released in the devolatilization/volatile oxidation stage of the reaction. The X-ray photoelectron spectroscopy r...

Carbon aerogels with biomimetic structures have shown excellent physicochemical properties and brought great potential applications to a wide range of fields. The utilization of renewable resources as the carbon precursors offers a low-cost and scalable way to fabricate biomimetic carbon aerogels with intriguing properties such as ultralight weight, superelasticity, and high conductivity. Inspired by the unique hierarchical mineral bridge structure of Thalia dealbata stem, we fabricated an ultralight, superelastic, highly conductive carbon aerogel (KGA) by using konjac glucomannan and graphene oxide as the carbon precursors. The unique mineral-bridged layered structure not only endows the carbon aerogel with a low density of 4.2 mg cm–3 but also a high electrical conductivity (12.9 S m–1). In addition, the carbon aerogel also exhibits a superelastic property of 80% maximal strain and no obvious degradation after 1000 cycles of compression. We demonstrated that this Thalia dealbata inspired carbon aerogel ...

Two-dimensional graphene has become one of the most intensively explored carbon allotropes in materials science owing to its attractive features, such as its outstanding physicochemical properties. To advance its practical application, the fabrication of self-assembled 2D graphene sheets into 3D nitrogen-doped graphene aerogels (NGA) with novel functions is becoming essential. Herein, the first attempts to modify graphene with Plectranthus amboinicus (PA), to introduce double nitrogen doping, and to prepare NGA by a natural drying (ND) method are reported. Natural drying was achieved by increasing the pore structure of NDPA-NGA using PA to simultaneously cross-link the graphene sheets and increase the stiffness of the sample. Meanwhile, we used ammonia and urea as double nitrogen sources to achieve an N-doping amount as high as 12.06 atom %. In addition, NDPA-NGA exhibited superelastic properties (with 95% maximal strain and almost no loss after 60 replicates), a high oil absorption capacity, and an excel...

Silver nanoparticles/silica nanowires (AgNPs/SiO2NWs) with the nearly uniform diameters of 35 ± 5 nm were successfully fabricated by two steps consisting of the preparation of the silica nanowires (SNWs) by chemical dispersing and acid leaching from the natural mineral chrysotile and an in situ reduction approach (for AgNPs). The highly dispersed AgNPs assembled on the surface of SiO2NWs through the in situ reduction of Ag+ by NaBH4 were confirmed by transmission electron microscopy (TEM) and UV–vis absorption spectra. The catalytic activities of the as-prepared Ag/SiO2NWs (silver nanoparticles/silica nanowires) nanocomposites with different concentrations were assessed via using a classical reaction based on the reduction process of 4-nitrophenol (4-NP) into 4-aminophenol (4-AP) in the presence of NaBH4 as the reductant. The results demonstrated that all the nanocomposite catalysts exhibited high catalytic activities because the nearly monodispersed AgNPs were embedded on the surface of SiO2NWs, allowing...