3D Grid of Carbon Tubes with Mn3O4-NPs/CNTs Filled in their Inner Cavity as Ultrahigh-Rate and Stable Lithium Anode

Transition metal oxides are regarded as promising candidates of anode for next-generation lithium-ion batteries(LIBs)due to their ultrahigh theoretical capacity and low cost,but are restricted by their low conductivity and large volume expansion during Li^(+)intercalation.Herein,we designed and constructed a structurally integrated 3D carbon tube(3D-CT)grid film with Mn_(3)O_(4)nanoparticles(Mn_(3)O_(4)-NPs)and carbon nanotubes(CNTs)filled in the inner cavity of CTs(denoted as Mn_(3)O_(4)-NPs/CNTs@3D-CT)as high-performance free-standing anode for LIBs.The Mn_(3)O_(4)-NPs/CNTs@3D-CT grid with Mn_(3)O_(4)-NPs filled in the inner cavity of 3D-CT not only afford sufficient space to overcome the damage caused by the volume expansion of Mn_(3)O_(4)-NPs during charge and discharge processes,but also achieves highly efficient channels for the fast transport of both electrons and Li+during cycling,thus offering outstanding electrochemical performance(865 mAh g^(-1)at 1 A g^(-1)after 300 cycles)and excellent rate capability(418 mAh g^(-1)at 4 A g^(-1))based on the total mass of electrode.The unique 3D-CT framework structure would open up a new route to the highly stable,high-capacity,and excellent cycle and high-rate performance free-standing electrodes for highperformance Li-ion storage.

Facile Synthesis of 3D Porous Flower-like ZnO Micro/nanostructure Films and Their Photocatalytic Performance

3D 在 Ti 底层上种的多孔的象花的 ZnO micro/nanostructure 电影经由热处理跟随的一种很灵巧的电极淀积技术被综合过程。ZnO 建筑学与极端薄表被装配，它由 nanoparticles 和毛孔的数字组成，并且 nanoparticles 的尺寸能被调整电极淀积时间或锻烧温度控制。这个合成方法能为另外的多孔的金属氧化物 nanostructure 电影提供一条有效线路，是值得注意的。而且， photocatalytic 表演证明多孔的 ZnO 是理想的光催化剂。

MoS_2 Nanosheet Arrays Rooted on Hollow rGO Spheres as Bifunctional Hydrogen Evolution Catalyst and Supercapacitor Electrode

MoS_2 has attracted attention as a promising hydrogen evolution reaction(HER) catalyst and a supercapacitor electrode material. However, its catalytic activity and capacitive performance are still hindered by its aggregation and poor intrinsic conductivity. Here, hollow rGO sphere-supported ultrathin MoS_2 nanosheet arrays(hrGO@MoS_2) are constructed via a dual-template approach and employed as bifunctional HER catalyst and supercapacitor electrode material. Because of the expanded interlayer spacing in MoS_2 nanosheets and more exposed electroactive S–Mo–S edges, the constructed h-rGO@MoS_2 architectures exhibit enhanced HER performance. Furthermore, benefiting from the synergistic effect of the improved conductivity and boosted specific surface areas(144.9 m^2 g^(-1), ca. 4.6-times that of pristine MoS_2), the h-rGO@MoS_2 architecture shows a high specific capacitance(238 F g^(-1) at a current density of 0.5 A g^(-1)), excellent rate capacitance, and remarkable cycle stability. Our synthesis method may be extended to construct other vertically aligned hollow architectures,which may serve both as efficient HER catalysts and supercapacitor electrodes.

Tunable structural color of anodic tantalum oxide films

Tantalum(Ta) oxide films with tunable structural color were fabricated easily using anodic oxidation.The structure,components,and surface valence states of the oxide films were investigated by using gazing incidence X-ray diffractometry,X-ray photoelectron microscopy,and surface analytical techniques.Their thickness and optical properties were studied by using spectroscopic ellipsometry and total reflectance spectrum.Color was accurately defined using L*a*b* scale.The thickness of compact Ta2O5 films was linearly dependent on anodizing voltage.The film color was tunable by adjusting the anodic voltage.The difference in color appearance resulted from the interference behavior between the interfaces of air-oxide and oxide-metal.

Novel closed-cycle reaction mode for totally green production of Cu_(1.8)Se nanoparticles based on laser-generated Se colloidal solution

Non-stoichiometric copper selenide(Cu_(2-x)Se,x=0.18~0.25)nanomaterials have attracted extensive attentions due to their excellent thermoelectric,optoelectronic and photocatalytic performances.However,efficient production of Cu_(2-x)Se nanoparticles(NPs)through a green and convenient way is still hindered by the inevitable non-environmentally friendly operations in common chemical synthesis.Herein,we initially reveal the coexistence of seleninic acid content and elemental selenium(Se)NPs in pulsed laser-generated Se colloidal solution.Consequently,we put forward firstly a closedcycle reaction mode for totally green production of Cu_(1.8)Se NPs to exclude traditional requirements of high temperature and toxic precursors by using Se colloidal solution.In such closed-cycle reaction,seleninic acid works as the initiator to oxidize copper sheet to release cuprous ions which can catalyze the disproportion of Se NPs to form Se O_(3)^(2-)and Se^(2-)ions and further produce Cu_(2-x)Se NPs,and the by-product SeO_(3)^(2-)ions promote subsequent formation of cuprous from the excessive Cu sheet.In experiments,the adequate copper(Cu)sheet was simply dipped into such Se colloidal solution at 70℃,and then the stream of Cu_(1.8)SeNPs could be produced until the exhaustion of selenium source.The conversion rate of Se element reaches to more than 75%when the size of Se NPs in weakly acidic colloidal solution is limited between 1 nm and 50 nm.The laser irradiation duration shows negative correlation with the size of Se NPs and unobvious impact to the p H of the solution which both are essential to the high yield of Cu_(1.8)SeNPs.Before Cu sheet is exhausted,Se colloidal solution can be successively added without influences to the product quality and the Se conversion rate.Such green methodology positively showcases a brand-new and potential strategy for mass production of Cu_(2-x)Se nanomaterials.

Synthesis and formation mechanism of HfB_(2) ultrafine powders with low oxygen via flocculating settling assisted process and carbo/borothermal reduction

In this study,ultrafine HfB_(2) powders with low oxygen were synthesized by a flocculating settling process which yielded ceramic precursors and subsequent carbo/borothermal reduction of the precursors.The liquid phase precursor method can achieve uniform mixing of components at the molecular level through multiple complexation reactions,and then realize the carbo/borothermal reduction reaction at a lower temperature to obtain ultrapure HfB2 powders.The as-resulted quasi-spherical HfB2 powders under the optimum conditions(atomic molar ratio M:B:C=1:2.8:10)calcined at 1500°C for 1 h have an average particle size of 205 nm and an oxygen content of 0.097 wt.%.Detailed analysis of the phase evolution of precursors shows that the formation of HfB2 particles is a mass diffusion mode from the external to internal HfO_(2)cores.We reveal that below 1300°C,HfC is not an intermediate product of HfB2 powder during the transition of precursors.Instead,HfC was formed as a by-product at high temperatures in the carbo/borothermal reduction process.The proposed formation mechanism of HfB_(2) is completely different from the traditional two-step transformation method.After the sintering of the ultrafine powders,the HfB_(2) ceramics show a relative density of 96.1%and superior mechanical properties compared to other works.Furthermore,by simply replacing the initial metal source,chlorinated group IV and V transitional metals(Ti,Zr,Ta,Nb)can also convert into high-purity and ultrafine diborides.This work shows that flocculating settling assisted carbo/borothermal reduction has potential in lot size production of various high-purity and ultrafine boride powders.

Diverse nanomaterials synthesized by laser ablation of pure metals in liquids

Diverse nanomaterials, in the forms of carbides, sulfides, oxides, metals, hydroxides, etc., have been synthesized by laser ablation in liquids(LAL) with metal targets as the dominant educts. Many advantages of LAL technique itself and its products have been revealed since 1983 when the first report about LAL was released. Different from traditional wet-chemical synthesis,one unique feature of LAL is its resultant extreme high-temperature and high-pressure local environment for the nucleation and growth of nanomaterials, despite being performed at room temperature. This extreme condition can induce the atomization and ionization of the target materials and liquid molecules to incur different chemical reactions. The laser, liquid, liquid additive, and target can significantly alter the local environment in a broad range. Thus, different phases and shapes of nanomaterials are producible even from the same target. Through directly comparing the products of LAL of 13 kinds of chosen representative metals synthesized under different conditions, this review presents and discusses current understandings, challenging issues, and perspectives related to the diversity of LAL-products, which is willing to promote a deeper investigation and discussion on a clear clarification of the chemical reactions and particle nucleation/growth processes.

Optical properties of mesoporous photonic crystals,filled with dielectrics,ferroelectrics and piezoelectrics

At present,it is very important to create new types of mirrors,nonlinear light frequency transformers and optical filters with controlled optical properties.In this connection,it is of great interest to study photonic crystals.Their dielectric permittivity varies periodically in space with a period permitting Bragg diffraction of light.In this paper,we have investigated the optical properties of mesoporous three-dimensional(3D)opal-type and one-dimensional(1D)anodic alumina photonic crystals,filled with different dielectrics,ferroelectrics and piezoelectrics.We have compared the optical properties of initial mesoporous photonic crystals and filled with different substances.The possibility of mesoporous photonic crystals using selective narrow-band light filters in Raman scattering experiments and nonlinear mirrors has been analyzed.The electromagnetic field enhancing in the case of exciting light frequency close to the stop band edges has been established.The optical harmonics and subharmonics generation in mesoporous crystals,filled with ferroelectrics and piezoelectrics was proposed.

Biological calcium phosphate nanorods for piezocatalytical extraction of U(VI)from water

The application of nanomaterials in energy and environmental fields has recently made great progress.As a key element in the nuclear industry,the discharge of uranium(U(VI))contained wastewater usually induces environmental issues and waste of resources.Although the catalytically generated H_(2)O_(2)by nanomaterials has recently shown application potential in extracting U(VI)from water,low-cost and highly efficient nanocatalysts are still urgently needed.In this work,a cheap and readily available piezocatalyst of calcium phosphate nanorods was successfully fabricated by calcining chicken bones.Under ultrasonication,H_(2)O_(2)was produced and used to extract U(VI)from water.It is worth noting that the yield of H_(2)O_(2)reached 179.7μmol·g^(−1)·h^(−1),and the extraction efficiency of U(VI)in water reached 97.16%(100 ppm)within 330 min.Through the capture and quantitative analysis of the active species,it is found that the generation of H_(2)O_(2)depends on the combination of soluble oxygen and piezoelectrons,which thus dominates the extraction of U(VI).This simple and powerful piezocatalytic strategy greatly reduces the cost of H_(2)O_(2)production for U(VI)extraction in water,and is of great significance for the treatment of U(VI)-containing wastewater.

Hexagonally arranged arrays of urchin-like Ag hemispheres decorated with Ag nanoparticles for surface-enhanced Raman scattering substrates

The surface topography of noble metal particles is a significant factor in tailoring surface-enhanced Raman scattering （SERS） properties. Here, we present a simple fabrication route to hexagonally arranged arrays of surface-roughened urchin- like Ag hemispheres （Ag-HSs） decorated with Ag nanoparticles （Ag-NPs） for highly active and reproducible SERS substrates. The urchin-like Ag-HS arrays are achieved by sputtering Ag onto the top surface of a highly ordered porous anodic aluminum oxide （AAO） template to form ordered arrays of smooth Ag-HSs and then by electrodepositing Ag-NPs onto the surface of each Ag-HS. Owing to the ordered arrangement of the Ag-HSs and the improved surface roughness, the urchin-like hierarchical Ag-HS arrays can provide sufficient and uniform ＂hot spots＂ for reproducible and highly active SERS effects. Using the urchin-like Ag-HS arrays as SERS substrates, 10-7 M dibutyl phthalate （a member of plasticizers family） and 1.5 × 10-5 M PCB-77 （one congener of polychlorinated biphenyl, a notorious class of pollutants） are identified, showing promising potential for these substrates in the rapid recognition of organic pollutants.

ZnO-nanotaper array sacrificial templated synthesis of noble-metal building-block assembled nanotube arrays as 3D SERS-substrates

这份报纸描述一个 ZnO-nanotaper 数组为有试管墙的 nanotubes 的数组的制造的合成途径由 Ag-nanoplates， Au-nanorods， Pt-nanothorns 或 Pd-nanopyramids 的大楼块装配了的牺牲的 templated，因此拥有高密度的 3D 在有 nano 尖端，角落或边的附近的积木的 sub-10-nm 差距的热点。另外，这些层次 nanostructure 数组与富有的表面化学拥有高表面区域，对捕获 analyte 有益。Ag-nanoplateassembled nanotube 数组能被用作散布的敏感提高表面的拉曼(重量的单位) 有好信号一致性和重制度的底层。用如此的 Ag ，层次 nanostructure 作为重量的单位底层穿，不是仅仅有 10 <啜class=“ a-plus-plus ”> 14 M 玫瑰精 6G 识别，而且 10 <啜class=“ a-plus-plus ”> 7 M polychlorinated 联本基(印刷电路板，坚持的器官的污染物质的一个臭名昭著的班)被认出，并且甚至印刷电路板的二同种的物能在混合物被识别，在环境器官的污染物质的基于重量的单位的快速的察觉显示出材料的潜在的应用。

提高锂离子电池负极的电化学储锂容量和倍率性能—三维互连碳管-NiO-SnO_(2)网格膜

二氧化锡(SnO_(2))具有高的理论比容量,有望作为下一代锂离子电池负极材料.然而,Sn向SnO_(2)的不可逆转化以及充放电过程中巨大的体积变化限制了其实际的应用.本文基于三维互连多孔氧化铝模板,设计合成了一种由内腔同时填充NiO和SnO_(2)纳米颗粒的碳管基元相互连接组成的三维碳管网格膜,可以直接作为自支撑的高性能锂离子电池负极.该复合框架利用了NiO和SnO_(2)纳米颗粒的协同作用,不仅能够促进Sn向SnO_(2)的可逆转变,提高首次库伦效率,而且还可以缓释充放电过程中SnO_(2)剧烈的体积变化.此外,相互连接的三维碳管框架可以负载大量NiO和SnO_(2)纳米颗粒,缩短Li+的扩散距离,并作为快速的电子传输通道.因此,这种独特的结构赋予了该电极超高的储锂容量和倍率性能在1 A g^(-1)循环200次后,比容量达到928.5 mA h g^(-1),并且在4 A g^(-1)的高电流密度下仍然具有633.5 mA h g^(-1)的比容量.总之,这种独特的一体化结构在锂离子电池等储能领域具有广阔的应用前景.

Ultrahigh-power electrochemical double-layer capacitors based on structurally integrated 3D carbon tube arrays

The rational design of electrodes is the key to achieving ultrahigh-power performance in electrochemical energy storage devices.Recently,we have constructed well-organized and integrated three-dimensional(3D)carbon tube(CT)grids(3D-CTGs)using a 3D porous anodic aluminum oxide template-assisted method as electrodes of electrical double-layer capacitors(EDLCs),showing excellent frequency response performance.The unique design warrants fast ion migration channels,excellent electronic conductivity,and good structural stability.This study achieved one of the highest carbon-based ultrahigh-power EDLCs with the 3D-CTG electrodes,resulting in ultrahigh power of 437 and 1708 W·cm−3 with aqueous and organic electrolytes,respectively.Capacitors constructed with these electrodes would have important application prospects in the ultrahigh-power output.The rational design and fabrication of the 3D-CTGs electrodes have demonstrated their capability to build capacitors with ultrahighpower performance and open up new possibilities for applications requiring high-power output.

Perspective on how laser-ablated particles grow in liquids

Laser ablation in liquids has emerged as a new branch of nanoscience for developing various nanomaterials with different shapes.However, how to design and control nanomaterial growth is still a challenge due to the unique chemical-physical process chain correlated with nanomaterial nucleation and growth, including plasma phase(generation and rapid quenching), gas(bubble) phase,and liquid phase. In this review, through summarizing the literature about this topic and comparing with the well-established particle growth mechanisms of the conventional wet chemistry technique, our perspective on the possible nanoparticle growth mechanisms or routes is presented, aiming at shedding light on how laser-ablated particles grow in liquids. From the microscopic viewpoint, the nanoparticle growth contains six mechanisms, including LaMer-like growth, coalescence, Ostwald ripening, particle(oriented) attachment, adsorbate-induced growth and reaction-induced growth. For each microscopic growth mechanism, the vivid growth scenes of some representative nanomaterials recorded by TEM and SEM measurements are displayed. Afterwards,the scenes from the macroscopic viewpoint for the large submicro-and micro-scale nanospheres and anisotropic nanostructures formation and evolution from one nanostructure into another one are presented. The panorama of how diverse nanomaterials grow during and after laser ablation in liquids shown in this review is intended to offer a overview for researchers to search for the possible mechanisms correlated to their synthesized nanomaterials, and more expectation is desired to better design and tailor the morphology of the nanocrystals synthesized by LAL technique.

碳纳米管/鸡蛋膜复合SERS衬底的制备及其应用（英文）

本文报道了一种利用具有均匀纤维网络结构的鸡蛋膜作为三维骨架,制备碳纳米管/鸡蛋膜复合表面增强Raman散射(SERS)衬底的简单廉价的方法.首先,借助超声吸附,将碳纳米管组装到经过前处理的鸡蛋膜纤维的表面,得到均匀的碳纳米管/鸡蛋膜复合膜;然后,借助溅射方法,将银纳米颗粒组装到碳纳米管和鸡蛋膜纤维的表面,得到银纳米颗粒修饰的碳纳米管/鸡蛋膜复合膜.这种方法制备的复合膜表面的碳纳米管对小分子目标分析物有很好的吸附和富集作用;同时,由于高密度银纳米颗粒的存在,衬底表面有大量的SERS活性位点,因此这种复合膜是一种有效的SERS衬底.研究表明,采用这种银纳米颗粒修饰的碳纳米管/鸡蛋膜复合SERS衬底,可实现对农药甲基对硫磷、多氯联苯以及生物分子牛血清蛋白等的快速痕量识别.由于该衬底的制备方法简单、原材料环保且来源广泛、衬底的活性高,所以该衬底在基于SERS技术对环境污染物和生物分子的快速痕量检测方面具有广泛的应用前景.

生长动力学控制化学气相沉积锗纳米塔（英文）

本文以简单的金催化常压化学气相沉积法,在单晶硅片上合成了塔状锗纳米结构(简称锗纳米塔).这种锗纳米塔的横截面为准六边形,从底端至顶端的尺寸逐渐减小,侧面含有锯齿状边缘.研究表明,锗纳米塔的形成主要是由相互竞争的生长过程决定的:在化学气相沉积过程中,由反应物蒸汽压调控的金催化的轴向生长与径向生长之间的竞争.这种生长动力学与产物复杂形貌之间的关系可以通过不同沉积区域获得的圆柱状、圆锥状锗纳米线以及念珠状、六角锥状锗纳米塔得到验证.这种锗纳米塔不仅丰富了锗纳米结构家族,而且在锗基功能纳米器件中有潜在的应用前景.