The etching strategy of zinc anode to enable high performance zinc-ion batteries

Zinc-ion batteries(ZIBs)are considered to be one of the most promising candidates to replace lithium-ion batteries(LIBs)due to the high theoretical capacity,low cost and intrinsic safety.However,zinc dendrites,hydrogen evolution reaction,surface passivation and other side reactions will inevitably occur during the charging and discharging process of Zn anode,which will seriously affect the cycle stability of the battery and hinder its practical application.The etching strategy of Zn anode has attracted wide attention because of its simple operation and broad commercial prospects,and the etched Zn anode can effectively improve its electrochemical performance.However,there is no comprehensive review of the etching strategy of Zn anode.This review first summarizes the challenges faced by Zn anode,then puts forward the etching mechanisms and properties of acid,salt and other etchants.Finally,based on the above discussion,the challenges and opportunities of Zn anode etching strategy are proposed.

Amphipathic Janus Nanofibers Aerogel for Efficient Solar Steam Generation

Solar steam generation is a promising water purification technology due to its low-cost and environmentally friendly applications in water purification and desalination.However,hydrophilic or hydrophobic materials alone are insufficient in achieving necessary characteristics for constructing highquality solar steam generators with good comprehensive properties.Herein,novel hydrophile/hydrophobe amphipathic Janus nanofibers aerogel is designed and used as a host material for preparing solar steam generators.The product consists of an internal cubic aerogel and an external layer of photothermal materials.The internal aerogel is composed of electrospun amphipathic Janus nanofibers.Owing to the unique composition and structure,the prepared solar steam generator integrates the features of high water evaporation rate(2.944 kg m^(-2)h^(-1)under 1 kW m^(-2)irradiation),selffloating,salt-resisting,and fast performance recovery after flipping.Moreover,the product also exhibits excellent properties on desalination and removal of organic pollutants.Compared with traditional hydrophilic aerogel host material,the amphipathic Janus nanofibers aerogel brings much higher water evaporation rate and salt resistance.

中国的二次分配与三次分配对收入极化的影响

发挥三次分配调节作用,对于降低收入极化,形成中间大、两头小的橄榄型分配结构,最终实现共同富裕,具有重要意义。本文基于CFPS居民微观调查数据,按照居民收入来源,采用MT指数法和循序分解步骤,解析了第二次分配和第三次分配对收入极化的再分配效应。研究结果表明:第二次分配和第三次分配显著降低了居民收入极化程度,且在城镇地区再分配效应更明显;总体而言,80%以上的再分配是通过公共转移收入来实现的,第三次分配降低市场收入极化的贡献不到20%;从转移收入类别来看,养老金的再分配效应最高,其次是政府补助、私人转移收入和社会捐助,而征地和拆迁补偿的再分配效应为负,即会加剧收入极化程度;各类转移收入的再分配效应与其规模弱的正相关而与其瞄准性弱的负相关。本研究表明,发挥三次分配调节作用、实现共同富裕,提高第三次分配的规模尤为重要,政策引导和鼓励社会组织参与第三次分配也需要重视。

Theoretical investigation of the doping effect on interface storage in the graphene/silicene heterostructure as the anode for lithium-ion batteries

Van der Waals heterostructures made up of different two-dimensional(2D)materials have garnered consider-able attention as anodes for lithium-ion batteries(LIBs),and doping can significantly influence their electronic structures and lithium diffusion barriers.In this work,the effects of heteroatom(X=N,O,P,and S)doping in the graphene of the graphene/silicene(G/Si)heterostructure are comprehensively examined by using first-principles calculations.The stacking stability and mechanical stiffness of G/Si and doped G/Si(XG/Si)exhibit that N-doping can improve the structural stability of G/Si,thereby ensuring good cycling performance.The densities of states reveal that the dopants(N,O,and S)can greatly increase the electronic conductivity of G/Si.Importantly,the adsorption and diffusion behaviors of Li are primarily affected by the dopant and the doping site,resulting in ultrafast Li diffusivity.Therefore,N-doped G/Si at doping site 1(S1)shows a good and balanced property,which exhibits high potential to enhance the electrical performance of G/Si materials and offers a reference for selecting dopants in other 2D anode materials for LIBs.

Decorating rare-earth fluoride upconversion nanoparticles on AuNRs@Ag core-shell structure for NIR light-mediated photothermal therapy and bioimaging

Photothermal therapy(PTT)has presented its inherent application value in cancer treatment.Nevertheless,single-functional photothermal materials cannot meet the precise diagnosis and treatment of cance r.Therefo re,it is important to design a nanocomposite that has both high therapeutic efficiency and multimodal imaging capabilities.In our work,a new nanostructure of gold nanorods(AuNRs)with silver shells decorated by BaGdF5:Yb^(3+),Er^(3+)nanoparticle was synthesized by a simple way.The biostability of AuNRs is increased by coating with silver shells,and the AuNR@Ag nanoparticles can be used as excellent surface enhanced Raman scattering(SERS)probe.Moreover,the modification of BaGdF5:Yb^(3+),Er^(3+)nanoparticles provides the possibility of real-time optical imaging of the tumor area.Under the irradiation of NIR laser,the AuNR@Ag/BaGdF5:Yb^(3+),Er^(3+)nanocomposites(NCs)have strong upconversion emission and excellent photothermal conversion efficiency.Meanwhile,the NCs show low cytotoxicity and good biocompatibility in MTT cytotoxicity test.Moreover,the NCs are also exceptional contrast agents for CT imaging.For in vitro photothermal therapy test,NCs show excellent killing efficiency on tumor cells.Therefore,the multifaceted research of AuNR@Ag/BaGdF5:Yb^(3+),Er^(3+)multifunctional nanomaterials provides a break for high-efficiency tumor photothermal therapy and multimodal imaging.

Eu^(3+)ions grafted polyacrylonitrile nanofibers possessing enhanced fluorescence performance by introducing benzoic acid as assistant ligand

Eu^(3+) ions were grafted onto the surface of electrospun polyacrylonitrile(PAN)nanofibers through coordination effect between C≡N groups on PAN nanofibers and Eu^(3+) ions,and benzoic acid(BA)was introduced as an assistant ligand.The impacts of concentrations of Eu^(3+) ions and BA,and reaction time on the properties of final products were investigated.The results reveal that Eu^(3+) ions can be successfully grafted onto PAN nanofibers,but the fluorescence intensity of the obtained PAN@Eu^(3+) nanofibers is very weak.After BA is introduced as the assistant ligand,the fluorescence intensity of the obtained PAN@(Eu^(3+)/BA)nanofibers is greatly stronger than that of PAN@Eu^(3+)nanofibers,and meanwhile,concentration quenching effect of Eu^(3+) ions can be effectively restrained.Furthermore,the superior structure of PAN@(Eu^(3+)/BA)nanofibers not only brings the effective utilization of precious elemental europium,but also guarantees high mechanical strength.