等离子体辅助球磨Si-C复合负极材料及其电化学性能研究

首次采用介质阻挡放电等离子体辅助高能两次球磨制得Si-C复合材料,其结构为微纳尺度硅颗粒均匀分散于微米级碳基体上. Si-C复合电极首周期循环放电容量为1259 mAh·g^-1,20和100周期循环的容量分别为474和396 mAh·g^-1. 该电极充放电曲线和交流阻抗测试的结果表明,复合材料中的硅和碳均参与锂离子嵌/脱反应,且其电荷传导阻抗明显低于纯Si.     

A comparative study on photoelectrochemical performance of TiO2 photoanodes enhanced by different polyoxometalates

Based on the incorporation of polyoxometalates (POMs) into TiO₂ film, the photoelectrochemical performance of POMs/TiO₂ anode was elucidated by comparative investigation on the electron transport and electron–hole recombination in POMs/TiO₂ anode. The photoelectrochemical performance of the POMs/TiO₂ anode was clearly dependent on the type and content of POMs. Compared to the TiO₂ anode, the POMs/TiO₂ anode with low POMs loadings (0.75%) displayed the enhanced photoelectrochemical performance, while the excessive content (7.5%) of POMs could almost cause a negative effect. Thus, POMs could act as either “shallow electron trap” or “deep electron trap” depending on the different types and contents of POMs. This study reveals that the introduction of POMs into TiO₂ anode could facilitate photogenerated electron transfer and reduce electron–hole recombination, which is urgently desired to develop advanced composite materials of POMs/TiO₂ for application in photoelectrochemical catalysis and solar cells.     

Durable High-Temperature Proton Exchange Membrane Fuel Cells Enabled by the Working-Temperature-Matching Palladium-Hydrogen Buffer Layer

The durability degradation during stack-operating conditions seriously deteriorates the lifetime and performance of the fuel cell. To alleviate the rapid potential rise and performance degradation, an anode design is proposed to match the working temperature of high-temperature proton exchange membrane fuel cells (HT-PEMFCs) with the release temperature of hydrogen from palladium. The result is significantly enhanced hydrogen oxidation reaction (HOR) activity of Pd and superior performance of the Pd anode. Furthermore, Pd as hydrogen buffer and oxygen absorbent layer in the anode can provide additional in situ hydrogen and absorb infiltrated oxygen during local fuel starvation to maintain HOR and suppress reverse-current degradation. Compared with the traditional Pt/C anode, the Pd/C also greatly improved HT-PEMFCs durability during start-up/shut-down and current mutation. The storage/release of hydrogen provides innovative guidance for improving the durability of PEMFCs.     

High lithiophilic nitrogen-doped carbon nanotube arrays prepared by in-situ catalyze for lithium metal anode

Lithium metal has a very outstanding theoretical capacity(3860 mAh/g) and is one of the most superior anode materials for high energy density batteries.However,the uncontrollable dendrite growth and the fo rmation of "dead lithium" are the important hidden dangers of short cycle life and low safety.However,the uncontrollable dendrite growth and the fo rmation of dead lithium leads to short cycle life and hidden dange r,which hinder its practical application.Controlling the nucleation and growth process of lithium is an effective strategy to inhibit lithium dendrite.Herein,a simple in situ self-catalytic method is used to construct nitrogen doped carbon nanotube arrays on stainless steel mesh(N-CNT@SS) as a lithium composite anode.The N-doped CNTs provide a great number of N-functional groups,which enhance the lithiophilic of anode and provide a large number of uniform nucleation sites,hence it has excellent structural stability for cycles.The arrays provide neat lithium-ion transport channels to uniform lithiumion flux and inhibits dendrite generation,revealed by the COMSOL multi-physics concentration field simulation.The N-CNT@SS composite anode sustain stable at 98.9% over 300 cycles at 1 mA/cm2.NCNT@SS as the anode is coupled LiFePO_4(LFP) as the cathode construct a full battery,demonstrating excellent cycling stability with a capacity of 152.33 mAh/g and capacity retaining ratio of 95.4% after 100 cycles at 0.5 C.     

Ru0.7Si0.3O2/Ti电极电催化氧化处理硝基苯废水

制备了Ru0.7Si0.3O2/Ti电极,并以该电极作为氧化阳极,不锈钢为阴极,电催化氧化降解废水中硝基苯。 实验结果表明,当硝基苯初始质量浓度为220 mg/L时,最佳条件为：电流密度25×10-3 A/cm2;Na2SO4作为电解质时加入量为8 g/L;溶液初始pH=2。 在此最佳条件下,硝基苯去除率大于85%,TOC去除率大于50%,表明Ru0.7Si0.3O2/Ti阳极能有效去除废水中有机污染物;对中间产物的检测结果表明,硝基苯的降解是阴阳两极协同作用的结果。     

基于不同前驱体制备的硬碳负极材料的储锂性能

以聚丙烯腈、石油沥青和花生壳为前驱体,在1200℃下碳化制备三种不同的硬碳材料.通过扫描电子显微、X射线衍射、氮气吸附/脱附测试和拉曼光谱等方法探究不同前驱体所制备的硬碳材料的表面形貌和物相结构.通过恒流充放电测试考察了这三种硬碳负极材料的电化学性能.结果表明,花生壳基硬碳的初始放电比容量最高,但首圈库仑效率最低,石油...     

Improvement of the charge imbalance caused by the use of a p-type silicon anode in an organic light-emitting diode

An indium-tin oxide anode was replaced with a p-type silicon anode in a bilayer small-molecule organic light-emitting diode. As results, the current increased largely due to the enhanced hole injection and the higher conductivity of the Si anode; the luminous efficiency decreased significantly due to carrier-induced exciton quenching and the worse charge imbalance. Ultra-thin film of SiO₂ grown on the silicon anode improved the luminous efficiency to a certain extent by restraining the hole injection; enhancing electron injection became more desired.     

Formation of NiO/YSZ functional anode layers of solid oxide fuel cells by magnetron sputtering

The decrease in the polarization resistance of the anode of solid-oxide fuel cells (SOFCs) due to the formation of an additional NiO/(ZrO₂ + 10 mol % Y₂O₃) (YSZ) functional layer was studied. NiO/YSZ films with different NiO contents were deposited by reactive magnetron sputtering of Ni and Zr–Y targets. The elemental and phase composition of the films was adjusted by regulating oxygen flow rate during the sputtering. The resulting films were studied by scanning electron microscopy and X-ray diffractometry. Comparative tests of planar SOFCs with a NiO/YSZ anode support, NiO/YSZ functional nanostructured anode layer, YSZ electrolyte, and La_0.6Sr_0.4Co_0.2Fe_0.8O₃/Ce_0.9Gd_0.1O₂ (LSCF/CGO) cathode were performed. It was shown that the formation of a NiO/YSZ functional nanostructured anode leads to a 15–25% increase in the maximum power density of fuel cells in the working temperature range 500–800°C. The NiO/YSZ nanostructured anode layers lead not only to a reduction of the polarization resistance of the anode, but also to the formation of denser electrolyte films during subsequent magnetron sputtering of electrolyte.     

电吸附除氯过程的电化学阻抗谱及动力学研究

借助三电极体系, 基于电化学交流阻抗谱图, 提出了一种对已吸附Cl^-的活性炭再次吸附一个Cl^-弛豫时间的测定方法, 根据弛豫时间确定速率控制步骤 . 研究了阳极电势、 预处理时间和预处理浓度对电化学过程的影响, 基于得到的电化学交流阻抗谱图上的参数, 求出不同条件下电吸附Cl^-的弛豫时间及覆盖度. 结果表明, 不同条件下得到的复数平面图均由一个容抗弧和一个感抗弧构成, 分别代表Cl^-在阳极上发生电荷转移的过程和 Cl^-在活性炭电极上的吸附过程 . 增加阳极极化可有效缩短弛豫时间, 阳极极化时, 弛豫时间为2.0×10^-5 s; 增加预处理时间, 弛豫时间逐渐增加, 预处理时间为180 min时, 弛豫时间增加到4.9×10^-5 s; 预处理浓度对弛豫时间的影响可忽略. 弛豫时间分析结果表明, Cl^-吸附速率比扩散速率小, 吸附是电吸附过程的速率控制步骤. 电极表面的覆盖度较低, 仅有10^-4...     

Gd_(0.2)Ce_(0.8)O_2包覆固体氧化物燃料电池Ni-ScSZ复合阳极制备及性能表征

应用双层流延法制备Ni-ScSZ阳极支撑体-ScSZ电解质复合膜素坯,经共烧结得到复合膜.以硝酸铈和硝酸钆为原料,柠檬酸作燃料,由燃烧合成法制备Gd0.2Ce0.8O2(GDC)包覆的Ni-ScSZ阳极.X-射线衍射(XRD)和电子显微镜(TEM和SEM)分析显示,Ni-ScSZ阳极颗粒表面的包覆层是由直径小于100 nm的GDC微粒构成,并与Ni-ScSZ阳极颗粒紧密烧结在一起.实验表明,2.0%(by mass)GDC包覆的Ni-ScSZ阳极具有较佳的性能,以其组装的单电池在850℃用H2或CH4作燃料的最大功率密度分别是825和848 mW/cm2,而由无包覆的Ni-ScSZ作阳极的单电池,功率密度分别是584和586 mW/cm2.由两种阳极材料组装的单电池,分别在700℃于CH4气氛下作长时间发电实验,发现2.0%(by mass)GDC包覆的Ni-ScSZ阳极比Ni-ScSZ阳极具有较好的抗碳沉积性能.     

Catalytic thermometric titrations in non-aqueous solvents by coulometrically generated titrant

Catalytic thermometric titrations have been developed for tertiary amines and salts of organic acids in acetic and propionic anhydride with titrant coulometrically generated at a mercury and/or platinum anode, hydroquinone being added to the solution titrated if the platinum anode is used. The results obtained are compared with those obtained by coulometric titration with the end-point detected either photometrically or potentiometrically. On a élaboré des titrages thermométriques catalytiques pour les amines tertiaires et les sels d'acides organiques en anhydrides aétique et propionique avec l'agent de titrage engendré coulométriquement sur une anode de mercure et/ou platine, de l'hydroquinone étant ajoutée à la solution titrée si l'on emploie l'anode de platine. Les résultats obtenus sont comparés avec ceux obtenus par titrage coulométrique avec le point de fin de réaction détecté soit photométriquement soit potentioétriquement.     

电容去离子除氯电极的构建及其脱盐性能研究进展

电容去离子技术(Capacitive deionization,CDI)是一种新兴的脱盐技术,通过在电极两端施加较低的外加电场除去水中的带电离子和分子,由于其较低的能耗和可持续性而备受关注。基于储能电池领域近年来的迅猛发展,CDI电极材料实现了从以双电层作用机理为代表的碳材料到法拉第电极材料的跨越,使得脱盐性能有了大幅度提升。Na⁺的去除与Cl^-的去除同等重要,然而,CDI中针对氯离子高效去除的电极材料研究关注较少。本文从CDI装置的构型演变发展出发,系统地归纳与梳理了CDI中关于脱氯电极材料的分类,对比了不同类型脱氯电极材料的特点,并总结了Cl^-去除的机理,分别为基于双电层的电吸附、转化反应、离子插层和氧化还原反应。本文是首篇关于CDI阳极材料的进展综述和展望,为CDI除氯电极的后续研究提供理论基础和研究思路。     

CeO2/RP-PSCFM@CoFe阳极材料用于质子导体乙烷燃料电池共生乙烯和电能

The continuous consumption and excessive use of fossil fuels promote the exploration of new energy conversion technologies. Meanwhile, the increase in the supply of ethane encourages the development of industrial technology for the production of ethylene chemical raw materials. Compared with traditional fossil fuel energy conversion equipment, solid oxide ethane cogeneration fuel cells are an efficient energy processing device. Through selective oxidation of fuel gas on the anode, the endothermic process of ethane dehydrogenation is converted into an exothermic oxidation reaction, which has a greater driving force for reaction thermodynamics, and simultaneously produces clean electricity and value-added chemicals without CO₂ emissions. The anode material used for the proton conductor ethane fuel cells needs to operate stably and efficiently under hydrocarbon fuel. Consequently, excellent catalytic activity, low polarization resistance, and anti-coking stability are essential. In this work, CeO₂ was uniformly impregnated into the surface of the porous cubic perovskite Pr_0.4Sr_0.6Co_0.2Fe_0.7Mo_0.1O_3−δ anode by wet impregnation, and then calcined and reduced to obtain a CeO₂/RP-PSCFM@CoFe composite anode embedded with nanoparticles, which was successfully used in electrolyte-supported proton conductor fuel cells. CeO₂ has a high ionic conductivity and transport capacity, which accelerates the transfer rate of protons on the anode and improves the catalytic reaction and transport process. Moreover, uniformly dispersed CeO₂ can effectively increase the three-phase interface of the anode reaction and increase the range of reaction activity. The peak power densities before and after wet impregnation reached 172 and 253 mW·cm⁻², respectively, at 750 ℃. When switching to ethane as the fuel, the peak power densities reached 136 and 183 mW·cm⁻², respectively. The polarization resistance of the impregnated single cell was significantly reduced, and the catalytic activity improved. Moreover, there was no attenuation for 10 h in the long-term test. Inversely, the current density increased with the continuous reduction of the composite anode. Product analysis revealed that the yield of ethylene increased from 23.52% at 650 ℃ to 34.09% at 750 ℃, and the ethylene selectivity exceeded 94%. These results clearly show that the impregnated anode exhibited excellent catalytic activity and anti-coking ability in hydrocarbon fuels at high temperatures. Combining CoFe nanoparticles with CeO₂ enhanced the electronic conductance and ionic conductance of the electrode, improved the transmission of electric energy and the efficient conversion of chemicals, thus successfully producing the cogeneration of electric energy and ethylene.     

Electrochemical Performance Studies of Tin Oxide Prepared by Sol-Gel

IntroductionSince the introduction of commercial lithium-ion batteries for the portable devices in the 1 990′s,the search for new anode materials with improvedenergy density and cycle- ability has never beenstopped[1— 5] .Graphite used as the early commercialanode material for lithium- ion batteries over otherkinds of materials in terms of its flat intercalationpotential and high cycle- ability[6,7] can′t keep pacewith the demand today because of its low capacity.In resentyears,the greateff…     

Study of the Anode Region of a DC Glow Discharge by a Spatially One-Dimensional Hybrid Method

The anode region of a dc glow discharge at low pressure and current is studied by a new self-consistent, spatially one-dimensional hybrid method. The method consists of the coupled solution of the steady-state fluid equations of electrons, ions, and excited atoms and the Poisson equation using the electron transport properties as well as the excitation and ionization frequencies from a strict solution of the non-uniform kinetic equation of the electrons. Results such as the electric potential, the electron velocity distribution function, and the densities of the charge carriers and excited atoms are reported for the anode region of neon glow discharges. Physical properties of the plasma in the anode region known from experiments have been confirmed by the model such as the occurrence of the anode fall, a formation of plateau-like areas of the potential profile in front of the anode, the anode dark space, and the anode glow.     

石墨负极电化学扫描循环过程的EIS、Raman光谱和XRD研究

运用电化学阻抗谱(EIS)、Raman光谱和XRD研究了石墨负极在1 mol/L LiPF6-EC∶DEC∶DMC电解液中的电化学循环扫描过程. EIS研究结果表明, 在电化学循环扫描4~10周范围内, SEI膜(固体电解质相界面膜)电阻随循环扫描周数增加近似线性增长, 但石墨负极/电解液界面总阻抗由于电荷传递电阻的降低而减小. Raman光谱研究结果表明, 在经历电化学循环扫描后, 活性材料表层发生粉化和无定形化, 石墨化程度降低; 但XRD研究结果显示, 石墨材料的本体结构没有发生变化, 仍然保持着完整的石墨层状结构.     

火试金法测定多金属复杂铜阳极泥中金

铜阳极泥中因含有大量金、银、铂、钯等贵金属而具有较高回收价值,其中金是价值最高的元素,金的精准检测对其综合回收具有重要指导意义。由于生产铜阳极泥的阳极板成分、生产指标控制、设备设施水平等因素的不同,导致其主要成分及含量均有较大差异,实验针对代表性的多金属复杂铜阳极泥,考察了多因素对火试金检测结果的影响。在硅酸度K=1.8、铅扣质量为35 g、氧化铅过量系数为1.8、熔炼温度为1100℃、熔炼升温时间和保温时间均为30 min时,加标回收率在99.4%~101%,RSD为0.15%~0.29%。优化条件下可实现多金属复杂铜阳极泥中金的精准检测。     

硬模板法制备固体氧化物燃料电池Ni_(0.5)Cu_(0.5)Ba_(0.05)O_x包覆管状SDC立体阳极

为在固体氧化物燃料电池中有效利用干甲烷为燃料,需制作多孔立体阳极。采用硬模板法和浸渍法制备Ni_(0.5)Cu_(0.5)Ba_(0.05)O_x包覆管状SDC阳极材料(Ni_(0.5)Cu_(0.5)Ba_(0.05)O_x/SDC),为作对比,用溶胶凝胶法制备粉末状Ni_(0.5)Cu_(0.5)Ba_(0.05)O_x,机械混合SDC粉末制备Ni_(0.5)Cu_(0.5)Ba_(0.05)O_x-SDC。将这两种阳极材料分别制作电解质支撑的单电池Ni_(0.5)Cu_(0.5)Ba_(0.05)O_x/SDC|YSZ|LSMYSZ与Ni_(0.5)Cu_(0.5)Ba_(0.05)O_x-SDC|YSZ|LSM-YSZ,并进行发电性能测试以及长期稳定性实验。结果表明,800℃下,干甲烷环境中,Ni_(0.5)Cu_(0.5)Ba_(0.05)O_x-SDC为阳极的单电池最大功率密度为324.99 m W/cm2,运行10 h后,电压下降5.60%;而以Ni_(0.5)Cu_(0.5)Ba_(0.05)O_x/SDC为阳极的单电池最大功率密度达到384.54 m W/cm2,运行100 h后,电压未严重衰减。实验后阳极的SEM照片表明,Ni_(0.5)Cu_(0.5)Ba_(0.05)O_x-SDC阳极内孔隙狭小,易被积炭堵塞;而Ni_(0.5)Cu_(0.5)Ba_(0.05)O_x/SDC阳极呈立体多孔结构,有利于燃料气体与反应后气体的扩散。催化剂颗粒均匀地包覆在SDC纤维管表面,有利于增加三相界面,提高电池的稳定性。     

A novel Mo-based oxide β-SnMoO_4 as anode for lithium ion battery

Recently,the development of new electrode materials for lithium-ion batteries(LIBs)has received intensive attention.As an important family of inorganic materials,mixed Mo-based transition metal oxides system is focused as anode materials.In the present work,a simple route has been adopted for the synthesis of layered-flake-likeβ-SnMo04 Nano-assemblies,which have been explored as potential anode materials for the first time in lithium-ion battery(LIB).Overall,the current reports on metal molybdate as anode materials are still rarely.As the anode material for LIBs,it was observed that the fabricated anode is capable of delivering a steady state capacity of almost 400 mAh/g up to 300 cycles under the influence of200 mA/g current density.Further,the anode material is suitable for use as a rated capacity anode because of its high current density tolerance.The present study can be further extended for the generation of a wide variety of other novel materials for multidisciplinary energy related applications.     

电催化氧化技术处理苯酚废水研究

电化学氧化法可有效处理挥发酚类废水,而阳极材料性能直接制约其电氧化效率.本文分别针对不锈钢、柔性石墨和SnO2 /Ti复合材料测定了其析氧过电位,并以不锈钢、柔性石墨为阳极材料,在 5~6V直流电压下,对合成苯酚废水进行了电化学氧化处理.结果表明:析氧过电位次序为SnO2 /Ti>柔性石墨 >不锈钢,处理后水的COD值接近或小于 100mg·L-1,且出水的苯酚浓度小于 0. 5mg·L-1.