Graphene exhibits outstanding mechanical,electrical,thermal,and optical properties,showcasing immense potential in enhancing the performance of polyimide composites.The unique two?dimensional characteristics of graphene allow for easy structural design and functional modification,presenting new opportunities for synthesizing polyimide composites with special functionalities.This review article provides a comprehensive overview of the research progress in graphene/polyimide nanocomposites in areas such as conductivity,mechanical properties,thermal properties and electromagnetic shielding.A systematic analysis was conducted on the influence of graphene's structure and functional modification on the performance of graphene/polyimide nanocomposites.Additionally,the application domains of different types of graphene/polyimide composites were discussed,with a detailed exploration of the interface interactions between graphene and the polyimide matrix and their impact on the properties of the nanocomposites.This article serves as a reference and inspiration for the subsequent development of multifunctional and high?performance graphene/polyimide nanocomposites.
Graphene oxide has become a popular material for research in recent years due to its unique physical and chemical properties. The preparation, functionalization, and application of graphene based composite membrane materials have become cutting?edge and popular topics. This article reviews the assembly methods and performance research of graphene oxide based composite membrane materials, including graphene oxide based composite Langmuir?Blodgett (LB) film, graphene oxide based composite electrospinning film, and other graphene oxide based composite films. It summarizes the recent research progress of graphene oxide based composite films and prospects their application prospects.
Controlling the use of fossil fuels and promoting the development of alternative new and clean energy sources is consistent with the theme of synergistic development between resource development and environmental protection. As a green energy source with high energy density, nuclear energy can be widely applied to alleviate the energy shortage in our country. The proven uranium resource content in seawater is more than 1 000 times higher than that in uranium mines. Extracting uranium from seawater is a potential way to ensure the long?term supply of uranium resource and the sustainable development of nuclear power. Adsorption has emerged as one of the effective methods for extracting uranium from seawater due to its advantages of high adsorption efficiency, simple operation, low cost, and environmentally friendly. However, the adsorption faces a number of challenges when extracting uranium from seawater, such as the extremely low concentrations of uranium in seawater and their stable existence in the form of Ca2UO2(CO3)3 or [UO2(CO3)3]4-, as well as a large variety and quantity of coexisting ions. Therefore, the preparation of high?performance adsorbents to achieve efficient and selective separation and enrichment of uranium in seawater is one of the important research topics in the field of environmental science. In this review, the types of adsorbents for uranium extraction from seawater and the performance enhancement strategies of their properties are briefly introduced, with the aim of helping researchers in this field design promising adsorbents for practical seawater uranium extraction.
Degradation of tetracycline(TC) is a challenge in the process of water pollution.A porous carbon material Zn@ZPC was obtained via direct roasting of ZIF?8 precursor and BiVO4 （BVO）was prepared by a hydrothermal method. Subsequently,a hybrid BVO/Zn@ZPCcomposites were prepared by in?situ heat treatment of Zn@ZPC and BVO.Meanwhile,the effects of the addition amount of BVO and roasting temperature on catalyst properties and photocatalytic performance were discussed in the process.The morphology and structure of the photocatalysts,the state of the metal species, and the pore structure were analysed by XRD,SEM,TEM,XPS,N2 adsorption?desorption,UV?vis DSR,and ESR techniques,respectively.The results showed that a Z?type heterojunction was formed between ZnO and BVO.In the experiments of photodegradation of tetracycline, BVO?40/Zn@ZPC?600 with a roasting temperature of 600 ℃and a BVO additive amount of 40 mg had the best photocatalytic degradation performance: under the irradiation of visible light,5 mg of the catalyst was able to completely degrade 100 mL TC(50 mg/L) within 60 min.
The development of efficient anode materials for carbon?based sodium ion batteries(SIBs) is a hot research topic. The prereduced graphene oxide(GO) was annealed at different temperatures to obtain wavy reduced graphene oxide(rGO) with different interlayer spacings for sodium?ion batteries(SIBs) anodes, and the electrolyte was further regulated to explore the relationship between the microstructure of graphene and sodium storage performance and sodium storage mechanism. The rGO anode after balancing the tuning layer spacing and conductivity shows a high initial coulombic efficiency of 82% in SIBs and excellent cycle stability of 93% capacity retention after 100 cycles through the sodium storage mechanism of intercalation and solvation Na+ co?adsorption in ether electrolyte.
To reveal complex light?matter interactions, it is necessary to simplify the on?demand design of metamaterials for both forward and inverse applications. Deep learning, a popular data?driven approach, has recently alleviated to a large extent the time?consuming and empirical nature of widely used numerical simulations.A fully?connected deep neural network?based framework for inverse design and spectral prediction of broadband absorbers was proposed.The results demonstrate and validate the high accuracy of the proposed DNN model at 87.47%.The model not only outperform traditional numerical algorithms while ensuring accuracy, but also provides an important reference for on?demand design performance of metamaterials.
In recent years, the research of sodium?ion batteries has received more and more attention, and transition metal oxides are considered to be the most potential cathode material system for industrialization due to their easy preparation, low cost, high capacity and high electrochemical activity. As the cathode material of ternary transition metal oxide sodium?ion battery, NaFe1/3Ni1/3Mn1/3O2 further improves the electrochemical performance of cathode materials on the basis of existing monic materials and binary materials. In this paper, the influence of conductive nanomaterial modification on its electrochemical performance was studied using ternary metal oxide NaFe1/3Ni1/3Mn1/3O2 as a model, and a doping strategy was provided to improve the cathode material performance of ternary transition metal oxide sodium?ion batteries.
Based on the first principles and wave function analysis theory,the one?photon absorption (OPA) spectra and two?photon absorption (TPA) spectra of the zigzag boundaries Twisted Bilayer Graphene Nanosheets (Z?TwBLG?NS) with different twist angles and their electronic excitation characteristics were studied.Firstly,the law and properties of the change of one?photon absorption spectrum and two?photon absorption spectrum with different twist angle were studied.Secondly,the characteristics of electron transition were analyzed visually.The results show that the absorption peaks are red?shifted to different degrees when the angle is not 0°,indicating that the angle modulates the absorption spectra of the system.The Z?TwBLG?NS with an angle of no 0° had obvious boundary effect, and the isosurface of electrons and holes were mainly distributed at the edge. Finally,the limiting effect of moiré pattern on electron transfer was revealed,which was reflected in the difference in the density of electrons and holes gathered in the moiré pattern.This study provides the analytical basis of physical mechanism for the generation of optical properties of Z?TwBLG?NS under the control of twist angle,as well as a research methodology for related research work.
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