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The height and width of Schottky barrier greatly reduce the electron injection efficiency. In this paper, high electron tunneling probability can be achieved by changing the interlayer distance of heterostructure.

Giant tunneling magnetoresistance (6.58 × 1010) is attained in an in-plane double-barrier magnetic tunnel junction based on Cr2C. This junction, due to its unique structural characteristics, has great potential applications in spintronic devices.

Chemical oxidation as a pretreatment step coupled with bioremediation for petroleum-contaminated soil may pose serious impacts on indigenous microorganisms and the available nutrients. Petroleum-contaminated soil were treated by hydrogen peroxide (H

The photocatalytic properties of Janus transition metal dichalcogenide (TMD) nanotubes are closely correlated with the electrostatic potential difference between their inner and outer surfaces (ΔΦ). However, due to some distraction from the tubular structures, it remains a great challenge to calculate their ΔΦ directly. Here, we creatively work out the ΔΦ of Janus MoSSe armchair single-walled nanotubes (A-SWNTs) with their corresponding building block models by first-principles calculations. The ΔΦ increases as the diameter reduces. After considering ΔΦ, we find that all of these MoSSe A-SWNTs possess suitable band-edge positions required for water redox reactions and high solar-to-hydrogen (STH) conversion efficiencies. The built-in field induced by the ΔΦ promotes the oxygen evolution reaction (OER) and hydrogen evolution reaction (HER) to proceed separately on the inner and outer surfaces. Especially, the photoexcited carriers exhibit adequate driving forces for OER and HER. Besides, constructing a double-walled nanotube can dramatically increase ΔΦ, which also further improves the separation and redox capacity of photoexcited carriers as well as the STH conversion efficiency. Moreover, all of these MoSSe armchair nanotubes have outstanding optical absorption in the visible light range. Our studies provide an effective strategy to improve the photocatalytic water-splitting performance of Janus TMD nanotubes.

Enhanced orange-red emitting Mn2+-doped CsPbCl3 nanocrystals with a near-unity photoluminescence quantum yield of up to 98% are synthesized through an AlCl3-assisted hot-injection route.

The HER activity of SnS2 nanosheet with transition metal doping and S vacancy defect was screened through DFT calculations. The modified pz band center combining with a new descriptor φ is proposed to predict the HER activity.

Achieving high spin polarization transport and pure spin current is particularly desired in spintronics. We use sawtooth graphene nanoribbon (STGNR) and its derived five-member ring structure (5-STGNR) to design new...

With the large-scale application and development of lithium-ion batteries, the extraction of lithium resources from salt lake brine has gradually become a global focus. Lithium titanium oxides (LTO)-type lithium ion-sieve (LIS) has attracted much attention due to its stable structure, high adsorption capacity, excellent recycling capacity, and environmental protection. In this review, we focused on the structure and adsorption mechanism of titanium-based ion sieves, and the preparation methods of different titanium oxide precursors. Furthermore, three modification methods including ion doping, morphology control, and surface coating were summarized. Finally, the insufficiency problem of current research is proposed, and the improvement and application of titanium-based LIS are prospected.

Monolayer phosphorene has outstanding mechanical flexibility, making it rather attractive in flexible spintronics that are based on 2D materials. Here, we report a first-principles study on non-equilibrium electronic-transport properties of the Co/phosphorene/Co magnetic tunnel junction (MTJ) with two α-Co electrodes. The magnetic moments of the two electrodes are considered in the parallel configuration (PC) and the anti-parallel configuration (APC). The tunneling current through the MTJ is investigated at a small bias from 0 to 40 mV when mechanical bending is applied on the MTJ with different central angle (

With the purpose of oil energy recovery as well as achieving efficiency of oil/water separation, hydrophobic mesh materials have attracted extensive attention. However, fabrication of the current methods is not environmentally friendly, has high energy consumption, and creates serious pollution. Inspired by lotus leaves and rose petals, a biomimetic superhydrophobic surface was fabricated prepared on a stainless steel mesh by an in situ chemical reduction method with simple operation and mild conditions. The results of SEM, XRD, and XPS demonstrated that the mesh shows a stable and uniform moss-like rough structured surface. The SSM/Ag/ODA mesh, which was modified by moss-like Ag nanoclusters and low surface energy agents, has excellent superhydrophobicity with an excellent oil/water separation efficiency that reached up to 99.8%. The silver mirror phenomenon formed by the Ag nanoclusters further confirmed that silver ions were reduced and attached to the surface of the mesh. Moreover, the mesh can maintain superhydrophobicity under harsh conditions, such as a high concentration of a salty solution, organic solvents, alkaline, acidic solution, and even long-time UV irradiation, etc. More importantly, the modified mesh has excellent physical stability, in which the water contact angle on the mesh can be maintained above 150° after harsh mechanical wear. The hydrophobic mesh showed great potential to be applied for highly efficient oil/water separation and oil energy recovery even under complex and harsh conditions.

Preparation of magnetic functional MOF-199 composites with good adsorption performance and easy recovery by solvothermal method for removal of thiophene from model oil. Study focused on the desulfurization performance of composites under different adsorption time, adsorption temperature, oil to adsorbent ratio, competitive adsorption, reuse times conditions. The morphology and structure of the composites were characterized by XRD, FTIR, BET, VSM and EDS. And the experimental results show that the adsorbent achieved the best desulfurization effect under the condition of 30 °C and the oil to adsorbent ratio was 100 for 240 min. The adsorption effect was Fe3O4–COOH/MOF-199(FCM) > Fe3O4–NH2/MOF-199(FNM) > Fe3O4/MOF-199(FM), which due to FCM exhibited a more powerful interaction between –COOH and thiophene base. In addition, the desulfurization performance of the adsorbents was affected by addition of competitors toluene and cyclohexene in the model oil. Adsorbent showed excellent desulfurization performance after 5 reuses. Webber–Morris model and Freundlich model are suitable to describe the desulfurization process of adsorbents.

Metal organic frameworks (MOFs) has broad application prospect in separation, catalysis, and adsorption. By a facile green method, we successfully fabricated prGO@cHKUST-1 composite membrane with the modification of dopamine and orientated growth of MOFs. Mg/Al-layered double hydroxides (Mg/Al-LDHs) was used as a modulator to obtain cubic HKUST-1 (cHKUST-1) with excellent morphology and special properties. Scanning Electron Microscopy (SEM), X-ray diffraction (XRD), and Fourier transform infrared spectroscopy (FTIR) etc. characterization illustrated successful synthesis of cHKUST-1 and composite membranes. Cubic HKUST-1 can tune the inter-layer spacing of graphene oxide (GO) leading increase in hydrophilicity and flux of the membrane. Meanwhile, the reduction effect of PDA and intercalation effect of MOFs could change the stacked way of GO layers, forming several fuzzy pores and more active sites on membrane surface. The prGO@cHKUST-1 membrane has an excellent rejection for methylene blue (MB) (99.5%) and Congo red (CR) (71.2%). Moreover, the modified membrane exhibited 10 and 5 times higher permeation flux than that of original GO membrane and prGO membrane, respectively. Thus, using orientated growth of MOFs to synthesize GO based composite membrane will provide useful insights in ultrahigh permeation flux membranes of dye and oil-water emulsion separation.

Walnut shell, a renewable and easy-accessible agricultural biowaste, was utilized as a precursor for the preparation of activated carbon materials with KOH activation in this study. After a series of activation processes, therefore, the activated carbon derived from walnut shells achieved a specific surface area of 1016.4 m2/g. With the advantage of low cost and environmental friendly, the prepared carbon materials have superior electrochemical performance and excellent prospects in the application of supercapacitor electrodes. The morphology and textural properties of the AC samples were examined by N2 adsorption–desorption, scanning electron microscopy, X-ray diffraction, X-ray photoelectron spectroscopy, and FTIR spectra. All the electrode samples exhibited excellent electrochemical performance. The AC-650 electrode achieved a maximum specific capacitance of 169.2 F/g at current density of 0.5 A/g in 6 M KOH electrolyte. This work provided an effective approach for the treatment and utilization of agricultural biowastes, which was worthwhile for economic, environmental, and societal viewpoints.

Numerous studies have confirmed that the apolipoprotein E4 allele (APOE4) gene and arteriosclerosis (AS) have a combined effect on the occurrence of cognitive function impairment, and dyslipidaemia levels are significantly correlated with APOE4 levels and AS. Few studies have focused on the combined effect of the APOE4 gene and AS on cognitive function. Therefore, this study aimed to investigate the effect of APOE4 gene and AS acting together on cognitive function through dyslipidaemia levels, which could provide certain scientific research value for future studies.A multi-stage cluster sampling method was used to investigate older adults aged 60 years and above in rural areas of Guizhou, China. The demographic sociological characteristics were collected, and laboratory tests, blood lipid measurements, and physical examinations were performed. Mini-Mental State Examination (MMSE) was used to determine cognitive function. Analysis of variance with two-factor factorial design was used to analyse the interaction between the APOE4 gene and AS on cognitive function and its domains.A total of 549 elderly subjects were eligible for this study. The result of the factorial design analysis revealed there was a significant interaction between the APOE4 gene and AS in terms of attention and numeracy (F = 6.878, P = 0.009).The combination of the APOE4 gene and AS leads to a decrease in the level of attention and numeracy domains, and certain attention should be focused on such populations in the future.

To improve the desulfurization adsorption performance of the magnetic hybrid material Fe3O4/HKUST-1, an innovative adsorbent Fe3O4/GO/HKUST-1 was synthesized. The desulfurization performance of Fe3...

Waste biomass and sewage sludge were used to obtain an adsorbent material with excellent performance qualities by adopting a KOH activation process via one-stage (ACone) or two-stage (ACtwo) co-pyrolysis. The main purpose of this work was to investigate the effects of both methods in terms of the physicochemical properties and adsorption capacities for methylene blue (MB). Textural analyses revealed that the surface area (Stot= 683.82 m2/g) and total pore volume (Vtot= 0.72 cm3/g) of ACtwo were more than two-fold compared with ACone (Stot= 285.33 m2/g; Vtot= 0.35 cm3/g). Thus, two-stage co-pyrolysis produced activated carbon with increased porosity, which was favorable for MB adsorption. Nevertheless, the intensity of the surface functional groups of ACtwo was weaker than for ACone, which could be due to the pore-forming mechanism. Two-stage co-pyrolysis increased the yield and aromaticity of activated carbon, but sufficient activation caused more functional groups to decompose. For the adsorbate MB, the maximum adsorption capacity of ACtwo (602.80 mg/g) was more than five-fold greater than that of ACone (101.88 mg/g), due to its excellent porosity properties. Furthermore, the interactions of MB molecules with activated carbon were via hydrogen bonds and electrostatic attraction. The adsorption process of MB onto activated carbon was accurately described by the pseudo-second-order kinetic model. Adsorption equilibrium evaluated Langmuir isotherms demonstrated that MB formed a monolayer by adsorption onto the activated carbon. Adsorption thermodynamics was used to investigate the influence of temperature on the adsorption process. Thermodynamic parameters indicated that MB adsorption onto activated carbon was spontaneous and endothermic. In conclusion, our results showed that two-stage co-pyrolysis improves the adsorption capabilities of activated carbon, so achieving better economic value from waste materials.

A nanocomposite of metal-organic frameworks (MOFs)-HKUST-1 based on graphene oxide (GO) was modified by polydopamine (PDA). These nanomaterials formed the PDA/RGO/HKUST-1 membrane over the surface of the commercial cellulose acetate membrane support layer to treat dye wastewater. The membranes were characterized by Fourier transform infrared spectroscopy, scanning electron microscopy, atomic force microscopy, X-ray diffraction, and X-ray photoelectron spectroscopy. The results showed enhanced membrane separation performance because of improved surface flatness and layer spacing. With the insertion of porous HKUST-1 and the cross-linking modification of PDA, the PDA/RGO/HKUST-1 membranes exhibited excellent flux, rejection, hydrophilic, and anti-fouling performance. The composite membrane could effectively reject methylene blue and Congo red, with removal rates of 99.8% and 89.2%, respectively. In addition, the flux of the PDA/RGO/HKUST-1 membrane increased 31-fold with the addition of HKUST-1 and PDA. Overall, the prepared high-flux composite membrane can be used as an excellent material in a variety of environmental applications.