微反应器内环酯类锂电池添加剂合成研究进展

锂电池电解液添加剂是一类在锂电池中用量不大,但对改善锂电池高低温性能,提高使用寿命和循环次数等方面发挥重要作用的高附加值电子化学品。随着锂电池等下游应用长期向好地发展,添加剂的需求量不断增长,但传统的釜式反应器由于传递性能不佳导致产品质量稳定性较差且污染严重。微反应器在微米尺度对流体有着高效分散和混合的优势,能显著提高生产效率、降低生产成本,在锂电池添加剂合成方面受到越来越广泛的关注。本文结合微反应器优异的传递性能,系统综述了微反应器在环酯类锂离子电池电解液添加剂合成中的应用进展,并对添加剂的微化工合成领域的研究方向进行了展望。

提高碱锰电池放电性能的研究进展(上)

碱锰电池的重负荷放电性能既与所使用的各种原材料有关,又取决于碱锰电池的工艺、结构设计以及生产工艺和装备。从碱锰电池制造厂商这方面来考虑,提高产品重负荷放电性能的技术措施着眼点为:①增加电池中活性物的填充量;②降低电池内阻;③改进产品的配方设计和结构设计;④使用添加剂。实际上,上述几个方面往往也是相互关联的。

Sorbitol-Electrolyte-Additive Based Reversible Zinc Electrochemistry

The unstable zinc(Zn)/electrolyte interfaces formed by undesired dendrites and parasitic side reactions greatly hinder the development of aqueous zinc ion batteries.Herein,the hydroxy-rich sorbitol was used as an additive to reshape the solvation structure and modulate the interface chemistry.The strong interactions among sorbitol and both water molecules and Zn electrode can reduce the free water activity,optimize the solvation shell of water and Zn^(2+)ions,and regulate the formation of local water(H_(2)O)-poor environment on the surface of Zn electrode,which effectively inhibit the decomposition of water molecules,and thus,achieve the thermodynamically stable and highly reversible Zn electrochemistry.As a result,the assembled Zn/Zn symmetric cells with the sorbitol additive realized an excellent cycling life of 2000 h at 1 mA·cm^(-2)and 1 mAh·cm^(-2),and over 250 h at 5 mA.cm^(-2)and 5 mAh.cm^(-2).Moreover,the Zn/Cu asymmetric cells with the sorbitol additive achieved a high Coulombic efficiency of 99.6%,obtaining a better performance than that with a pure 2 mol-L^(-1)ZnSO_(4)electrolyte.And the constructed Zn/poly1,5-naphthalenediamine(PNDA)batteries could be stably discharged for 2300 cycles at 1 A g^(-1)with an excellent capacity retention rate.This result indicates that the addition of 1 mol-L^(-1)non-toxic sorbitol into a conventional ZnSO_(4)electrolyte can successfully protect the Zn anode interface by improving the electrochemical properties of Zn reversible deposition/decomposition,which greatly promotes its cycle performance,providing a new approach in future development of high performance aqueous Zn ion batteries.

滴流床式反应器合成氯代碳酸乙烯酯的研究

滴流床反应器是一种气-液-固三相催化反应器,气液并流向下或逆流而上的方式,借助固态催化剂床层,被绝大部分石油化工企业所运用,同时石油炼制、精细化学工程、环境治理工程、污水处理工程等项目应用也较为广泛。滴流床反应器在特殊领域以及特定需求的催化要求下有着无可替代的竞争优势。现有的氯代碳酸乙烯酯催化反应基本上为反应釜式反应器,对于光催化反应,由于光能量的损失,对内部反应影响较大,易形成过度化反应,进而影响产品的含量以及杂质数量。氯代碳酸乙烯酯是气液式反应,比较适合滴流床式反应装置,文章对滴流床式氯化反应进行了相关研究,通过不断改进实验方案,以得到最优实验效果。

碳酸亚乙烯酯的合成方法综述

碳酸亚乙烯酯(VC)是一种重要的锂离子电池电解液添加剂,主要用于磷酸铁锂电池和三元锂电池中,是目前使用量最大的电解液添加剂。本文综述了碳酸亚乙烯酯的合成方法并分析评价,展望了今后碳酸亚乙烯酯的合成研究方向。

硫酸乙烯酯的合成方法综述

硫酸乙烯酯是一种新型锂离子电池电解液添加剂。综述了目前已报道的硫酸乙烯酯及其关键中间体的合成方法,并对现有的合成方法进行初步分析评价,进一步展望了今后硫酸乙烯酯的合成研究方向。

Effects of additives on performance of zinc electrode

In order to improve the properties of the nickel?zinc battery and study the effects of the additives on performance of zinc electrode, 3 levels and 4 factors (acetylene black, Bi2O3, PbO, Ca[Zn(OH)3]2·2H2O coated by La(OH)3 ) that affect the zinc electrode were tested with orthogonal design experiments. The charge?discharge experiments of zinc electrode made up of only zinc oxide were done in 20% KOH solution to investigate the function of the additive. In order to better understand the discharge capability attenuation of electrode, the ratios of zinc to calcium in the worst sample and the best sample of the orthogonal design test were analyzed. The samples were characterized by charge?discharge cycling, phase structure analysis, cyclic voltammetry and X-ray diffraction. Experimental evidences indicate that the optimum ratio of electrode additive is as follows: 0.02 g acetylene black, 0.5 g Bi2O3, 0.3 g PbO and 0.2 g Ca[Zn(OH)3]2·2H2O coated with La(OH)3 in 5 g sample.

减压精馏-熔融结晶分离1,3-丙烷磺内酯的研究

为了达到锂离子电池电解液添加剂的品质要求,在制备电子级1,3-丙烷磺内酯的过程中,采用了减压蒸馏-熔融结晶的提纯工艺。工业级1,3-丙烷磺内酯通过减压蒸馏,在135～145℃之间得到了纯度为99. 0%～99. 5%的粗产品,经熔融结晶精制后,产品纯度可达99. 9%以上。另研究发现,1,3-丙烷磺内酯粗产品的纯度只有达到99. 0%以上时,通过一次熔融结晶后的纯度才能达到99. 9%以上,且收率可达90%以上。

Electrodeposition and characterization of Cu2O thin films using sodium thiosulfate as an additive for photovoltaic solar cells

Cuprous oxide （Cu2O） thin films have been grown by electrodeposition technique onto ITO-coated glass substrates from aqueous copper acetate solutions with addition of sodium thiosulfate at 60 ℃ The effects of sodium thiosulfate on the electrochemical deposition of Cu2O films were investigated by cyclic voltammetry and chronoamperometry techniques. Deposited films were obtained at - 0.58 V vs. SCE and characterized by X-ray diffraction （XRD）, Fourier transform infrared spectroscopy （FrIR）, scanning electron microscopy （SEM）, and optical, photoelectrochemical and electrical measurements. X-ray diffraction results indicated that the synthesized Cu2O films had a pure cubic phase with a marked preferential orientation peak along （200） plane and with lattice constants a = b = c = 0.425 rim. FFIR results confirmed the presence of Cu2O films at peak 634 cm 1. SEM images of Cu2O films showed a better compactness and spherical-shaped composition. Optical properties of Cu2O films reveal a high optical transmission （〉80%） and high absorption coefficient （α 〉 104 cm- 1 ） in visiblelight region. The optical energy band gap was found to be 2.103 eV. Photoelectrochemical measurements indicated that Cu2O films had n-type semiconductor conduction, which confirmed by Hall Effect measurements. Electrical properties of Cu2O films showed a low electrical resistivity of 61.30 Ω. cm-1, carrier concentration of-4.94×1015cm -3andmobility of20.61cm2.V 1,s-l.Theobtained Cu2O thin films with suitable properties are promising semiconductor material for fabrication of photovoltaic solar cells,

Effect of Additives on the Performance of Lead Acid Batteries

Effect of titanium dioxide （TiO2） and carbon additives in the respective positive and negative material properties and the influence on the performance of the battery were investigated. The electrode samples were characterized by BET （Brunauer Emmett Teller）, XRD （X-ray diffractometer）, SEM （scanning electron microscopy） and EIS （electrochemical impedance spectroscopy） to understand the surface area, phase, structure, morphology and electrical conductivity of the respective electrode material. The surface area was obtained as 2.312 m2＂g＂l and 0.892 m2＂g＂1, respectively for 12% of activated carbon in the expander of negative and 0.70% of TiO2 （Titanium dioxide） in the PAM （positive active material）. The structural analysis reveals an increase in the tetrabasic lead sulfate and also evidenced by well grown crystals in the PAM with the TiO2, respectively obtained by XRD and SEM techniques. The impedance spectra analysis shows an increase of electrical conductivity of negative active mass with temperature. The battery results showing two fold enhancements in the charge acceptance were attributed to the high surface area activated carbon in the NAM （negative active material）. The materials properties of electrodes and their influence on the battery performance were discussed.

Effect of additives on the photovoltaic properties of organic solar cells based on triphenylamine-containing amorphous molecules

Photovoltaic performance of the organic solar cells （OSCs） based on 2-（（5＇-（4-（（4-（（E）-2-（5＇-（2,2-dicyanovinyl）-3＇,4-dihexyl- 2,2＇-bithiophen-5-yl）vinyl） phenyl）（phenyl）amino）styryl）-4~4＇-dihexyl-2,2＇-bithiophen-5-yl）methylene）malononitrile （L（TPA- bTV-DCN）） as donor and PC70BM as acceptor was optimized using 0.25 vol% high boiling point solvent additive of 1-chloronaphthalene （CN）, 1,6-hexanedithiol （HDT）, or 1,8-diodooctane （DIO）. The optimized OSC based on L（TPA-bTV- DCN）-PC70BM （1：2, w/w） with 0.25 vol% CN exhibits an enhanced power conversion efficiency （PCE） of 2.61%, with Voc of 0.87 V, Jsc of 6.95 mA/cm2, and FF of 43.2%, under the illumination of 100 mW/cm2 AM 1.5 G simulated solar light, whereas the PCE of the OSC based on the same active layer without additive is only 1.79%. The effect of the additive on absorption spectra and the atomic force microscopy images of L（TPA-bTV-DCN）-PCv0BM blend films were further investigated. The improved efficiency of the device could be ascribed to the enhanced absorption and optimized domain size in the L（TPA-bTV-DCN）-PC70BM blend film.

Synergistic improvement of perovskite film quality for efficient solar cells via multiple chloride salt additives

Perovskite crystal film quality is critical for obtaining efficient perovskite solar cells. Anti-solvent processing was used for fast crystallization of perovskite precursor film, which can form dense perovskite film. However, the crystals from this method are usually small due to the fast crystal growth process, which could lead to grain boundary recombination. Here, element chloride is introduced to enhance the perovskite layer crystallinity via slowing down the perovskite crystallization process by simultaneous introduction of methylammounium chloride （MACI） and cesium chloride （CsCl） into precursor solution. As a result, we achieve high quality of pin-hole free perovskite film with large crystal size. A power conversion efficiency of 21.55% with free of hysteresis of the device is obtained, which is among the highest efficiency of planar structure perovskite solar cells.

Performance improvement of organic bulk heterojunction solar cells by using dihydroxybenzene as additive

We report the enhanced performance of organic solar cells(OSCs) based on regioregular poly(3-hexylthiophene)(P3HT) and methanofullerene [6,6]-phenyl C61-butyric acid methyl ester(PCBM) blend by using dihydroxybenzene as additive in the active layer.The effect of the content of the additives on electrical characteristics of the device is studied.The device with 0.2 wt% dihydroxybenzene additive achieves the best power conversion efficiency(PCE) of 4.58% with Jsc of 12.5 mA/cm2,Voc of 0.65 V,and FF of 66.6% under simulated solar illumination of AM 1.5G(100 mW/cm2),compared with the control device with PCE of 3.39%(35% improvement compared with the control device).The XRD measurement reveals that the addition of additives induces the crystallization of P3HT and establishes good inter-network to increase the contact area of donor and acceptor,and then helps charge to be effectively transferred to the electrode to reduce the chance of recombination.All evidences indicate that the dihydroxybenzene is likely to be a promising new type additive that can enhance the performance of organic bulk heterojunction solar cells.

The electrochemical performance of super P carbon black in reversible Li/Na ion uptake

Super P carbon black (SPCB) has been widely used as a conducting additive in Li/Na ion batteries to improve the electronic conductivity. However, there has not yet been a comprehensive study on its structure and electrochemical properties for Li/Na ion uptake, though it is important to characterize its contribution in any study of active materials that uses this additive in non-negligible amounts. In this article the structure of SPCB has been characterized and a comprehensive study on the electrochemical Li/Na ion uptake capability and reaction mechanisms are reported. SPCB exhibits a considerable lithiation capacity (up to 310 mAh g^(–1)) from the Li ion intercalation in the graphite structure. Sodiation in SPCB undergoes two stages: Na ion intercalation into the layers between the graphene sheets and the Na plating in the pores between the nano-graphitic domains, and a sodiation capacity up to 145 mAh g^(–1) has been achieved. Moreover, the influence of the type and content of binders on the lithiation and sodiation properties has been investigated. The cycling stability is much enhanced with sodium carboxymethyl cellulose (NaCMC) binder in the electrode and fluoroethylene carbonate (FEC) in the electrolyte; and a higher content of binder improves the Coulombic efficiency during dis-/charge.