Applying Double Electric Fields to Avoid Deteriorating Movable Sensitive Parts in MEMS During Anodic Bonding

Anodic bonding between silicon and glass with dou bl e electric fields is presented.By this means,the damage caused by the electric f ield to the movable part during bonding can be avoided and the experiment result s show that.

Effects of polyaniline on electrochemical properties of composite inert anodes used in zinc electrowinning

In order to search for a suitable anode material used in zinc electrowinning in place of Pb-Ag alloy,Al/Pb-PANI（polyaniline）-WC（tungsten carbide） composite inert anodes were prepared on aluminum alloy substrate by double pulse electrodeposition（DPE） of PANI and WC particles with Pb2＋ from an original plating bath.Thereafter,anodic polarization curves,cyclic voltammetry curves and Tafel polarization curves for the composite inert anodes obtained under different PANI concentrations in the original plating bath were measured,and the microstructural features were also investigated by scanning electron microscopy（SEM）.The results show that Al/Pb-PANI-WC composite inert anode obtained under PANI concentration of 20 g/L in the original plating bath possesses uniform microstructures and composition distributions,higher electrocatalytic activity,better reversibility of electrode reaction and corrosion resistance in a synthetic zinc electrowinning electrolyte of 50 g/L Zn2＋,150 g/L H2SO4 at 35 °C.Compared with Pb-1%Ag alloy,the overpotential of oxygen evolutions for the composite inert anode are decreased by 185 mV and 166 mV,respectively,under 500 A/m2 and 1000 A/m2.

Double perovskite oxides Sr_2Mg_(1-x)Fe_xMoO(6-δ) for catalytic oxidation of methane

The double perovskite oxides Sr2Mg1-xF exMoO6-δ were investigated as catalysts for the methane oxidation.The structural properties of catalysts were characterized in detail by X-ray diffraction,X-ray photoelectron spectroscopy and X-ray absorption spectroscopy.The catalytic property was strongly influenced by the Fe substitution.The relation between catalytic performance and the degree of Fe substitution was examined with regard to the structure and surface characteristics of the mixed oxides.The Fe-containing catalysts exhibited higher activity attributable to the possible（Fe2＋,Mo6＋） and （Fe3＋,Mo5＋）valency pairs,and the highest activity was observed for Sr2Mg0.2Fe0.8MoO6-δ.The enhancement of the catalytic activity may be correlated with the Fe-relating surface lattice oxygen species and was discussed in view of the presence of oxygen vacancies.

Selenium(Ⅵ) removal from caustic solution by synthetic Ca-Al-Cl layered double hydroxides

To extract selenium(Ⅵ)from the highly caustic leachate of copper anode slime,the Ca-Al-Cl layered double hydroxides(Ca-Al-Cl-LDHs)with a formula of Ca2 Al(OH)6 Cl·2 H2 O by three co-precipitation methods were synthesized.A plate-like morphology and hexagonal crystal structure with typical mineral phases and functional groups were identified by the FESEM,XRD,FTIR,BET and XPS analysis.The forward feeding sample exhibits the best adsorption capacity of Se(Ⅵ).The factor experiments then reveal a favorable adsorption process with low temperature,low NaOH concentration and high adsorbent dosage.Furthermore,the adsorption kinetics and isotherm parameters can be well described by the Langmuir isotherm and the pseudo-second-order models,respectively.Accordingly,the maximum adsorption amount of Se(Ⅵ)onto Ca-Al-Cl-LDHs reaches188.6 mg/g at 50 ℃.

Dual-function protective layer for highly reversible Zn anode

The thermodynamic instability of zinc anodes in aqueous electrolytes leads to issues such as corrosion,hydrogen evolution reactions(HER), and dendrite growth, severely hindering the practical application of zinc-based aqueous energy storage devices. To address these challenges, this work proposes a dualfunction zinc anode protective layer, composed of Zn-Al-In layered double oxides(ILDO) by rationally designing Zn-Al layered double hydroxides(Zn-Al LDHs) for the first time. Differing from previous works on the LDHs coatings, firstly, the ILDO layer accelerates zinc-ion desolvation and also captures and anchors SO_(4)^(2-). Secondly, the in-situ formation of the Zn-In alloy phase effectively lowers the nucleation energy barrier, thereby regulating zinc nucleation. Consequently, the zinc anode with the ILDO protective layer demonstrates long-term stability exceeding 1900 h and low voltage hysteresis of 7.5 m V at 0.5 m A cm^(-2) and 0.5 m A h cm^(-2). Additionally, it significantly enhances the rate capability and cycling performance of Zn@ILDO//MnO_(2) full batteries and Zn@ILDO//activated carbon zinc-ion hybrid capacitors.This simple and effective dual-function protective layer strategy offers a promising approach for achieving high-performance zinc-ion batteries.

Polyzwitterionic cross-linked double network hydrogel electrolyte enabling high-stable Zn anode

Zn metal anode suffers from dendrite issues and passive byproducts,which severely plagues the practical application of aqueous Zn metal batteries.Herein,a polyzwitterionic cross-linked double network hydrogel electrolyte composed of physical crosslinking(hyaluronic acid)and chemical crosslinking(synthetic zwitterionic monomer copolymerized with acrylamide)is introduced to overcome these obstacles.On the one hand,highly hydrophilic physical network provides an energy dissipation channel to buffer stress and builds a H_(2)O-poor interface to avoid side reactions.On the other hand,the charged groups(sulfonic and imidazolyl)in chemical crosslinking structure build anion/cation transport channels to boost ions’kinetics migration and regulate the typical solvent structure[Zn(H_(2)O)_(6)]^(2+)to R-SO_(3)^(−)[Zn(H_(2)O)_(4)]^(2+),with uniform electric field distribution and significant resistance to dendrites and parasitic reactions.Based on the above functions,the symmetric zinc cell exhibits superior cycle stability for more than 420 h at a high current density of 5 mA·cm^(−2),and Zn||MnO_(2)full cell has a reversible specific capacity of 150 mAh·g^(−1)after 1000 cycles at 2 C with this hydrogel electrolyte.Furthermore,the pouch cell delivers impressive flexibility and cyclability for energy-storage applications.

Generation scenarios of anodic structures and experimental realization of turbulence in unmagnetized plasma

In the present work,we report development of a DC glow discharge plasma(GDP)set-up to study controlled evolution of anodic structures having distinctive geometry,size and layers,generated in front of a positively biased electrode,submerged in unmagnetized plasma.For such an anodic structure,we have also investigated the condition under which the turbulence is triggered.Characteristic of these structures,generated in front of a positively biased electrode,depends on multiple parameters such as the ratio of anode to cathode size,electrode separation,gas pressure,biasing configuration such as anode bias,cathode bias and grounding schemes.We attempted to classify different anodic structures observed experimentally,as anode glow,fireball,anode spot,double layer and multiple double layers(MDLs)based on its physical characteristics.Among these structures the present investigation is focused on MDLs.The number of layers,observed in MDLs varied from as high as six to as low as zero,by controlling the operating discharge parameters,externally.Diagnostics were carried out using Langmuir probe.The analysis of floating potential fluctuations corresponds to a multiple anodic structure showed emergence of turbulence,at its critical stage,satisfying condition for self-organized criticality(SOC).This was identified with three slopes observed in the power spectrum,resembling the sand-pile model.Though,the GDP is completely different from that of the magnetically confined plasma,the nature of turbulence observed with SOC,is very similar to that observed in the scrape of layer of fusion devices.Therefore,the present investigation could provide new approach to study turbulence of similar nature,under an experimental condition that is free from the complexities of complicated field geometries used in confinement devices.

Extended Anode Effect for Tube Inner Coating of Non-Conductive Ceramics by Pulsed Coaxial Magnetron Plasma

For uniform tube inner coating of non-conductive thin films, the double-ended coaxial magnetron pulsed plasma (DCMPP) method was investigated. In this study, coating of TiN and TiO2 was performed. It was clearly shown that the extended anode effect was strongly influenced by the electric resistance of the coated thin films on the inner surface of an insulator tube. Additionally, high frequency (100 kHz) was better for relatively high plasma density. On the other hand, in the case of titanium oxide deposition, negative ion productions drastically decrease the deposition rate and the shifting velocity of plasma main position for coated TiO2 films.

Two-Step Anodization of Maltilayer TiO_2 Nanotube and Its Photocatalytic Activity under UV Light

A double-layer TiO2 nanotube arrays were formed by two-step anodization of Ti foils in different electrolytes. First, Ti in 0.5 wt% HF was anodized to form thin nanotube layer. Afterwards a second anodization was conducted in a formamide based electrolyte, which allowed the second layer of nanotube growing directly underneath the first one. From FESEM investigation we found that the thickness of second layer corresponded to the anodization time, the increasing of which would lead to the excessive etching on the first layer. The first layer protected the lower one from fluoride corrosion during anodization process. The double layer TiO2 nanotube arrays showed no benefit to photodegradation effect in methyl orange degradation experiments.

氧硫双掺杂CNTs水系导电剂辅助构筑高性能石墨/SiO负极

由于石墨具有资源丰富、比容量高和嵌锂电位低等优势,被视为重要的商业化锂离子电池(LIBs)负极材料。然而,石墨较低的理论比容量限制了LIBs能量密度的进一步提升。因此,本文将少量的氧化亚硅(SiO)添加到石墨中,再分散到少量的氧硫掺杂双壁碳纳米管(O,S-DCNTs)水系导电剂中,得到石墨/SiO复合负极。其中,O,S-DCNTs是通过将双壁碳纳米管(DCNTs)在空气中预氧化处理,再通过浸渍法与MgSO4混合后煅烧所得的,具有纳米孔结构丰富、硫含量高和亲水性强等特性。通过电池性能测试发现,引入O,S-DCNTs后石墨/SiO复合负极的比容量、倍率和循环性能得到显著提升。此外,其循环性能是纯硫掺杂碳纳米管(S-DCNTs)石墨/SiO负极的4倍,这主要归因于高分散的O,S-DCNTs能够构筑大量的导电网络,提供丰富的锂离子存储空间和活性位点,解决SiO导电性差和体积膨胀系数大问题,从而显著提高石墨负极的电化学性能。本文为高性能负极材料的制备与储能应用提供了新的思路和方向。

镍钴水滑石纳米笼/GO复合材料在锂离子电池负极中的应用

近年来,水滑石(LDH)材料因其组成、结构和形貌易于调节,具有丰富的活性位点,被认为是高性能锂离子电池(LIBs)负极的替代材料,然而水滑石作为负极仍存在电导率差和结构易聚集等问题.于此同时,金属有机框架(MOFs)及碳基材料也由于其优秀的孔隙率、比表面积以及良好的电导率在储能领域得到了广泛的关注.考虑到这二者有望对LDH的主要缺陷有所改进,提出了将原位沉淀、化学刻蚀法和静电吸附法相结合,使镍钴水滑石纳米笼(H-(Ni,Co)-LDHP)能够固定在GO上,从而得到镍钴水滑石纳米笼/氧化石墨烯复合材料(H-(Ni,Co)-LDHP/GO).这种GO上密集分布的中空纳米结构更能有效抑制水滑石纳米片的聚集,并有利于锂离子的脱嵌.H-(Ni,Co)-LDHP/GO纳米复合材料作为锂离子电池的负极,在电流密度为50m A·g^(-1)下,循环第一圈库伦效率可达68%,循环50圈后电容保留率为68.4%.

Double core-shell nanostructured Sn-Cu alloy as enhanced anode materials for lithium and sodium storage

Sn-based alloy materials are considered as a promising anode candidate for lithium-ion batteries(LIBs)and sodium-ion batteries(SIBs),whereas they suffer from severe volume change during the discharge/charge process.To address the issue,double core-shell structured Sn-Cu@SnO2@C nanocomposites have been prepared by a simple co-precipitation method combined with carbon coating approach.The double core-shell structure consists of Sn-Cu multiphase alloy nanoparticles as the inner core,intermediate SnO2 layer anchored on the surface of Sn-Cu nanoparticle and outer carbon layer.The Sn-Cu@SnO2@C electrode exhibits outstanding electrochemical perfor-mances,delivering a reversible capacity of 396 mA·h·g^-1 at 100 mA·g^-1 after 100 cycles for LIBs and a high initial reversible capacity of 463 mA·h·g^-1 at 50 mA·g^-1 and a capacity retention of 86% after 100 cycles,along with a remarkable rate capability(193 mA·h·g^-1 at 5000 mA·g^-1)for SIBs.This work provides a viable strategy to fabricate double core-shell structured Sn-based alloy anodes for high energy density LIBs and SIBs.

双阳极电Fenton法处理纺织印染废水

针对传统工艺处理纺织印染废水效率低、成本高等问题,研究了采用双阳极电Fenton法处理纺织印染废水的工艺条件,以江西省某纺织印染企业之废水为研究对象,通过单因素控制变量法,分析各因素对其处理效果的影响。结果表明:在柱状活性炭(Ф=4 mm)投加量为400 g/L,电解电压为10 V,H_(2)O_(2):Fe~(2+)(摩尔比)为20:1,FeSO_(4)·7H_(2)O投加量为1.6 g/L,电解质(NaCl)投加量为1 g/L的条件下,双阳极电Fenton体系的处理效果最佳,反应3 h后,COD去除率为90.46%,色度去除率为98.99%,UV_(254)去除率为98.85%。将铁泥作为双阳极电Fenton体系之铁源,在pH为2,投加量为1.46 g/L,其他条件相同,COD去除率为90.05%,色度去除率为98.17%,UV_(254)去除率为98.28%。双阳极电Fenton体系能够有效处理纺织染料废水,对废水的色度、UV_(254)和COD均有较高的去除率,铁泥作为铁源构建双阳极电Fenton体系为铁泥资源化利用提供了一个新的选择。

钛酸锂/碳双层包覆氧化亚硅基负极材料及其电化学性能研究

通过化学气相沉积和溶胶-凝胶法制备了钛酸锂/碳双层包覆的氧化亚硅基锂离子电池负极材料。电化学测试结果表明,钛酸锂包覆量3%时,负极材料性能较好,在0.2C、0.5C、1C、2C、4C倍率下的比容量分别为1 485.4、1 443.8、1 386.4、1 341、1 276.2 mAh/g,在电流密度750 mA/g下循环150次后比容量为1 138.1 mAh/g。柔韧的碳层可以缓冲内部硅芯的体积膨胀并提高材料电导率,刚性的钛酸锂可以保证材料结构完整性,双壳层协同作用有效提升了电极材料的循环稳定性、倍率性能和可逆容量。

快充型锂离子电池负极片设计的研究

为解决锂离子电池高体积能量密度和快充的技术矛盾,本文基于包覆石墨和双层电极结构设计了两组负极片。一组是将包覆石墨与非包覆石墨混合使用,另一组是采用双层涂布技术制备了具有双层结构的负极片,表层是包覆石墨,底层是非包覆石墨。使用两组负极片分别制备出了软包锂离子电池,通过测试电池内阻、充电速度、循环等性能来考察负极片设计对快充型电池性能的影响。实验结果表明,双层结构负极片具备更优的充电速度和循环性能,更适合于快充型锂离子电池。

大气压直流双阳极等离子弧脉动特性研究

等离子弧的脉动特性是表征等离子体物理状态和过程的重要参数之一,等离子体射流的非稳定性和阳极斑点在电极上的运动是引起等离子弧脉动的主要原因,是等离子体技术的实际应用和进一步发展的关键。该文介绍了一种大气压直流双阳极等离子发生器,通过对等离子弧电信号进行时域和频域分析,研究了载气成分、载气流量和弧电流等参数的变化对等离子弧脉动特性的影响,结果表明在文中的实验条件下等离子弧的伏安特性呈上升趋势,纯氩气作为载气时等离子弧的脉动特性主要和电源的交流分量有关,氩氮混合气体作为载气时等离子弧的脉动特性除了和电源的交流分量有关,还和弧室内存在的赫姆霍茨共振有关,其共振频率独立于气体流量和弧电流的变化。

钛-铁双阳极电絮凝法去除电镀废水中的铬(Ⅵ)

对采用钛-铁双阳极电絮凝技术去除电镀废水中铬(Ⅵ)进行了研究。以铬(Ⅵ)去除率为考察指标,利用单因素试验和正交试验,详细研究了不同阳极材料及组合方式、电流密度、电解时间、废水pH、电导率、静置时间等因素对其去除废水中铬(Ⅵ)效果的影响,经正交试验的极差分析和方差分析表明:对质量浓度为0.2g/L的含铬(Ⅵ)模拟废水,当电流密度控制在1.5A/dm2,电解时间为1.5h,电解质NaCl质量浓度为1.0g/L及废水pH=9时,铬(Ⅵ)的去除率最高,达96.57%。在此基础上应用于处理实际镀铬废水,获得了满意的结果。同时,初步探讨了钛-铁双阳极电絮凝法除铬(Ⅵ)机理,得出氧化和絮凝作用,是废水中铬(Ⅵ)被有效去除的主要原因。

天然气燃料电池中双层阳极Ni-SDC的性能

采用干压方法制备双层阳极支撑的以BCY20(BaCe0.8Y0.2O3-δ)为电解质的固体氧化物燃料电池。双层阳极的质量分数分别为60%NiO+40%SDC(Ce0.8Sm0.2O2-δ)和30%NiO+70%SDC。阴极采用质量分数分别为85%LSCF(La0.9Sr0.1Co0.2Fe0.8O3-δ)+15%GDC(Ce0.8Gd0.2O2-$)复合阴极。在400～600℃的范围内,用天然气为燃料气,氧气为氧化气,50℃为间隔,测试并比较了该电池与单层阳极支撑电池(阳极质量分数为50%NiO+50%SDC、阴极为85%LSCF+15%GDC复合阴极、电解质为BCY20)的性能。用扫描电镜(SEM)分别分析单电池阳极、阴极及电解质的型貌。实验表明:电池具有良好的微结构,在测试条件下双层阳极支撑电池具有更优的性能。600℃测得电池最大比功率为55mW/cm2,电流密度为253mA/cm2。

阳极双电层电容对微生物燃料电池性能的影响

采用3种活性炭粉制备具有不同电容的阳极,研究了双电层电容阳极对单室空气阴极微生物燃料电池启动、运行、性能、阳极生物膜附着的影响。结果表明:当电极表面积相近的情况下,阳极双电层电容从0.0012 F增加到22.72 F时,微生物燃料电池启动时间缩短了68.0%,电池的最大功率密度增加了16.8倍,达到546.1 m W·m-2。扫描电子显微镜的结果表明高电容的阳极表面附着的微生物量比低电容电极的高1倍。因此,微生物燃料电池性能受阳极双电层电容的影响,而与阳极表面积的相关性小。

W波段回旋行波管双阳极磁控注入电子枪的设计

回旋行波管是大功率、高频率的微波毫米波器件。根据W波段回旋行波管的要求,设计了双阳级磁控注入电子枪。由电子光学理论,计算得到电子枪的初始参量,然后利用粒子模拟软件MAGIC构造电子枪模型,分析电子枪各个参数对电子注性能的影响,为电子枪设计优化提供了一定的依据。最后优化得到符合设计要求的低速度零散电子枪结构。电子枪阳极电压为70kV,电流10A,电子注速比1.07,电子注横向速度零散0.8%。