Characterization,Electrical Conductivity and Electrochemical Performance of Polyaniline-LiClO4-CuO Nano Composite for Energy Storage Applications

Polyaniline (PANI), PANI/LiClO₄ composite with 5% & 10% of salt and PANI/LiClO₄/CuO NPs (PLC) nanocomposite were synthesized by chemical method and characterized them with help of fourier transform infrared spectrometer (FT-IR) spectrometer to investigate the chemical interaction between salt and confirmed the composite formation. Field emission scanning electron microscope (FESEM) is used to study the morphological changes in the composite due to effect of salt and formation of long fiber structures. provide the conducting path between the polymer matrix and the Li⁺ ions helps to increase conductivity. The absorbance study reveals shifting of absorption wavelength towards higher end with increasing salt content in PANI is attributed to the π→π* electron transition in the benzenoid and quinoid rings. The optical band gap (E_g) found decreasing from 2.88 to 2.35 eV for 10% of salt and 2% CuO nano NPs due to forming delocalized charges in host polymer. The dielectric parameters, and AC conductivity against frequency at different temperatures were studied. The PANI/LiClO₄ composites are electrochemically stable upto 1000^th cycle with 213.08 F/g specific capacitance at 3mA/g current density for10% of salt.     

石墨烯基材料的组装和电化学储能应用

石墨烯作为一种新型二维碳材料,因其独特的结构和优异性质受到广泛关注,在众多领域具有广阔的应用空间。然而由于石墨烯片层间存在较强的相互作用,在实际应用过程中极易发生团聚,从而造成片层利用率低以及性能的急剧降低。因此,利用石墨烯的二维基元结构特点,通过组装实现石墨烯片层的有序性搭接以提高其片层的利用率,对石墨烯材料的实际应用具有重要意义。本文归纳了近年来不断出现的石墨烯基材料的组装体及组装方法,重点介绍了不同形态石墨烯组装体的结构特点及其在电化学储能器件中的潜在应用。     

生物大分子印迹聚合膜的表征及电化学应用

使用扫描电子显微镜(SEM)、红外图谱(IR)、循环伏安(CV)、差示脉冲循环伏安(DPV)对血红蛋白聚合物膜修饰电极进行了表征。DPV测试表明血红蛋白的浓度和峰电流分别在低浓度和高浓度下均有良好的线性关系,低浓度下满足线性回归方程ip(μA)=13.05-3.58C(μM),相关系数R为-0.9960。检出限为2.7×10-9M,线性范围8.0×10-9~7.1×10-7M;高浓度下满足线性回归方程Ip(μA)=10.56-0.1001C(μM),相关系数R为-0.9957。检出限为5.7×10-7M,线性范围1.7×10-6~1.4×10-5M。可用于构建生物分子印迹的电化学传感器。     

Hypoglycaemic and Hypolipidaemic Effects of Withania somnifera Root and Leaf Extracts on Alloxan-Induced Diabetic Rats

Withania somnifera is an important medicinal plant, which is used in traditional medicine to cure many diseases. Flavonoids were determined in the extracts of W. somnifera root (WSREt) and leaf (WSLEt). The amounts of total flavonoids found in WSREt and WSLEt were 530 and 520 mg/100 g dry weight (DW), respectively. Hypoglycaemic and hypolipidaemic effects of WSREt and WSLEt were also investigated in alloxan-induced diabetic rats. WSREt and WSLEt and the standard drug glibenclamide were orally administered daily to diabetic rats for eight weeks. After the treatment period, urine sugar, blood glucose, haemoglobin (Hb), glycosylated haemoglobin (HbA1C), liver glycogen, serum and tissues lipids, serum and tissues proteins, liver glucose-6-phosphatase (G6P) and serum enzymes like aspartate transaminase (AST), alanine transaminase (ALT), acid phosphatase (ACP) and alkaline phosphatase (ALP) levels were determined. The levels of urine sugar, blood glucose, HbA1C, G6P, AST, ALT, ACP, ALP, serum lipids except high density lipoprotein-bound cholesterol (HDL-c) and tissues like liver, kidney and heart lipids were significantly (p < 0.05) increased, however Hb, total protein, albumin, albumin:globulin (A:G) ratio, tissues protein and glycogen were significantly (p < 0.05) decreased in alloxan-induced diabetic rats. Treatment of the diabetic rats with WSREt, WSLEt and glibenclamide restored the changes of the above parameters to their normal level after eight weeks of treatment, indicating that WSREt and WSLEt possess hypoglycaemic and hypolipidaemic activities in alloxan-induced diabetes mellitus (DM) rats.     

Conducting Polymer Nanostructures: Template Synthesis and Applications in Energy Storage

Conducting polymer nanostructures have received increasing attention in both fundamental research and various application fields in recent decades. Compared with bulk conducting polymers, conducting polymer nanostructures are expected to display improved performance in energy storage because of the unique properties arising from their nanoscaled size: high electrical conductivity, large surface area, short path lengths for the transport of ions, and high electrochemical activity. Template methods are emerging for a sort of facile, efficient, and highly controllable synthesis of conducting polymer nanostructures. This paper reviews template synthesis routes for conducting polymer nanostructures, including soft and hard template methods, as well as its mechanisms. The application of conducting polymer mesostructures in energy storage devices, such as supercapacitors and rechargeable batteries, are discussed.     

血红蛋白在海藻酸钠膜中的电化学和类酶活性研究

用海藻酸钠(SA)将血红蛋白(Hb)固定到热裂解石墨电极表面,制备了Hb-SA膜修饰电极。包埋在SA膜中的Hb在磷酸盐缓冲溶液和乙醇混合溶液中与电极直接传递电子,得到一对对称的血红蛋白辅基血红素Fe(Ⅲ)/Fe(Ⅱ)电对的可逆氧化还原峰。其式电势随缓冲溶液pH值增加而负移,且呈线性关系,这说明血红蛋白的电子传递过程伴随有质子的转移。并考察了Hb-SA膜修饰电极在缓冲溶液和乙醇混合溶液中对氧气、双氧水、一氧化氮和六氯乙烷的电催化性质。     

Film Blowing of Biodegradable Polymer Nanocomposites for Agricultural Applications

Films for agricultural applications, such as greenhouses films or mulching films are generally made of polyolefins such as linear low-density polyethylene (LLDPE) or low-density polyethylene. However, the use of biodegradable and/or compostable polymers is increasing, which enjoy the additional advantage that they can be left on the site since a fine life would be gradually assimilated to the underlying soil. Nevertheless, biodegradable polymeric films often do not have suitable mechanical performances. In this work, biodegradable polymer-based nanocomposite films are prepared by film blowing and compared with traditional LLDPE based nanocomposites. In particular, a biodegradable polymer blend and two different inorganic nanofillers (an organo-modified clay and a calcium carbonate with a hydrophobic coating) are used for the preparation of the nanocomposites. A detailed investigation of obtained materials is performed through rheological, mechanical, and optical characterizations. Adding nanofillers led to an increase of rigidity and tear strength of blown films without negatively affecting their ductility.     

固定化辣根过氧化物酶的电化学和电催化特性

用海藻酸钠(SA)将辣根过氧化物酶(HRP)固定到热裂解石墨电极表面,制备了HRP-SA膜修饰电极。研究发现包埋在SA膜中的辣根过氧化物酶可与电极直接传递电子,在缓冲溶液中可得到一对辣根过氧化物酶辅基血红素Fe(Ⅲ)/Fe(Ⅱ)电对的可逆氧化还原峰。其式电势随溶液pH值增加而负移,且呈线性关系,这说明辣根过氧化物酶的电子传递过程伴随有质子的转移。并考察了HRP-SA膜修饰电极对氧气、双氧水、一氧化氮的电催化性质。     

应用于低温加热的肉豆蔻酸和硬脂酸共熔混合物的储热特性

Stearic acid （67.83℃） and myristic acid （52.32℃） have high melting temperatures that can limit their use as phase change material （PCM） in low temperature solar heating applications such as solar space and greenhouse heating in regard to climatic requirements. However, their melting temperatures can be adjusted to a suitable value by preparing a eutectic mixture of the myristic acid （MA） and the stearic acid （SA）. In the present study, the thermal analysis based on differential scanning calorimetry （DSC） technique shows that the mixture of myristic acid （MA） and stearic acid （SA） in the respective composition （by mass） of 64% and 36% forms a eutectic mixture having melting temperature of 44.13℃ and the latent heat of fusion of 182.4J.g^-1. The thermal energy storage characteristics of the MA-SA eutectic mixture filled in the annulus of two concentric pipes were also experimentally established. The heat recovery rate and heat charging/discharging fractions were determined with respect to the change in the mass flow rate and the inlet temperature of heat transfer fluid. Based on the results obtained by DSC analysis and by the heat charging/discharging processes of the PCM, it can be concluded that the MA-SA eutectic mixture is a potential material for low temperature thermal energy storage applications in terms of its thermo-physical and thermal characteristics.     

Direct-Ink-Writing of Electroactive Polymers for Sensing and Energy Storage Applications

Considering the high levels of materials used in the fields of electronics and energy storage systems, it is increasingly necessary to take into consideration environmental impact. Thus, it is important to develop devices based on environmentally friendlier materials and/or processes, such as additive manufacturing techniques. In this work, poly(vinylidene fluoride) (PVDF) and poly(vinylidene fluoride-co-hexafluoropropylene) (PVDF-HFP) are prepared by direct-ink-writing (DIW) by varying solvent evaporation temperature and fill density percentage. Different morphologies for both polymers are obtained, including dense films and porous membranes, as well as different electroactive β-phase content, thermal and mechanical properties. The dielectric constant and piezoelectric d₃₃ coefficient for dense films reaches up to 16 at 1 kHz and 4 pC N⁻¹, respectively for PVDF-HFP with a fill density of 80 and a solvent evaporation temperature of 50 °C. Porous structures are developed for battery separator membranes in lithium-ion batteries, with a highest ionic conductivity value of 3.8 mS cm⁻¹ for the PVDF-HFP sample prepared with a fill density of 100 and a solvent evaporation temperature of 25 °C, the sample showing an excellent cycling performance. It is demonstrated that electroactive films and membranes can be prepared by direct-ink writing suitable for sensors/actuators and energy storage systems.     

钠化累托石/海藻酸钠插层纳米复合膜的结构及性能研究

用水溶液共混法制备出钠化累托石(Na+REC)/海藻酸钠(SA)插层纳米复合膜Na+REC/SA,通过XRD及TEM分析了复合材料的结构及插层机理,系统研究了复合膜的透光性、力学性能、抗紫外老化性、气液阻隔性及热性能.实验结果表明,Na+REC添加量较少时可与SA形成插层型纳米复合膜.Na+REC添加2%时,膜的插层效果及性能最佳,相对SA膜其拉伸强度提高58.7%,断裂伸长率提高100%,40%失重率对应的热分解温度提高了185℃,复合膜经紫外辐射后拉伸强度保持率达89.6%,断裂伸长保持率达到74.9%,且膜有良好的透光性及气液阻隔性.     

电能存储技术研究现状与发展趋势

对电能存储的重要性进行了简要说明,着重介绍了抽水储能、压缩空气储能、飞轮储能、锂离子电池、铅酸电池、液流电池、钠硫电池、超级电容器和超导储能。分别指出各种储能方式的优、缺点和发展现状,并提出未来储能技术的发展趋势。     

A Lead‐Free and High‐Energy Density Ceramic for Energy Storage Applications

In this work, we demonstrate a very high‐energy density and high‐temperature stability capacitor based on SrTiO₃‐substituted BiFeO₃ thin films. An energy density of 18.6 J/cm³ at 972 kV/cm is reported. The temperature coefficient of capacitance (TCC) was below 11% from room temperature up to 200°C. These results are of practical importance, because it puts forward a promising novel and environmentally friendly, lead‐free material, for high‐temperature applications in power electronics up to 200°C. Applications include capacitors for low carbon vehicles, renewable energy technologies, integrated circuits, and for the high‐temperature aerospace sector.     

类石墨烯材料在能量储存转换领域的应用

随着高效电池、超级电容器、储氢材料成为清洁高效能源计划中的研究重点,类石墨烯材料由于具有与石墨烯类似的结构及其革新性能,逐渐成为能源计划中的研究前沿.简要介绍了类石墨烯材料的基本结构及其“自上而下”和“自下而上”的制备方法.综述了类石墨烯材料作为电极材料在二次电池和超级电容器中的应用,以及作为储氢载体在储氢装置中的应用.探讨了类石墨烯材料在能量储存转换领域的应用,分析比较了其优缺点,展望了其前景.     

饲用碘酸钙/海藻酸钠微胶囊的制备及其稳定性

为隔绝饲用碘酸钙[Ca(IO3)2]在贮存过程中与还原性物质,如维生素C(VC)的反应,以Ca(IO3)2为芯材,海藻酸钠(SA)为壁材,纳米碳酸钙(Nano-CaCO3)为交联钙源,采用改良的内源乳化法制备了碘酸钙/海藻酸钠微胶囊(CISAMC)。利用FTIR、SEM、TG、XRD对其进行了结构表征,同时测定了其在VC水溶液中的稳定性,探讨了CISAMC的形成机制。结果表明,CISAMC呈球形,粒径约为10～40μm,表面有大量Ca(IO3)2晶体。Ca(IO3)2和CISAMC在VC水溶液中VC分解50%用时(t50%)分别为54.8和78.3 min,CISAMC使Ca(IO3)2在饲料中的稳定性得到明显提升。     

基于金属有机骨架氧化物模板法的空心NiO的制备及其储钠电化学性能

本工作以镍离子交换的金属有机骨架氧化物Co-ZIF-67为模板制备得到空心NiO材料,并通过SEM、XRD、BET、FTIR、XPS、恒流充放电测试、循环伏安曲线等表征手段对空心NiO的结构、形貌、表面特性和电化学性能进行分析。SEM和BET测试表明制备的NiO为表面具有纳米中孔的亚微米级的空心材料。XPS结果显示空心氧化镍表面Ni为+2价和+3价的混合价态,作为钠离子电池负极时,电流密度50 m A·g~(-1)条件下初始比容量能达到1133.6 m Ah·g~(-1),充电比容量达到549.7 m Ah·g~(-1),首次循环库仑效率为48.5%;50次循环后,放电比容量仍能达到330.1 m Ah·g~(-1),表现出优异的可逆储钠性能。     

Swelling and Diffusion Characteristics of Interpenetrating Network Films Composed of Sodium Alginate and Gelatin: Transport of Azure B

Interpenetrating polymer network (IPN) films have been made from two hydrophilic natural polymers, namely, sodium alginate (NaAlg) and gelatin (Gltn) in the presence of glycerol (Glrl) using Ca²⁺ as crosslinkers. Films have been prepared with varying amounts of crosslinking agent, plasticizer and the component polymers. The effect of these parameters, the preparation conditions and the pH of the medium on the swelling behavior of these gel films has been investigated. Dynamic swelling studies have been carried out and the kinetic parameters for the swelling process have been evaluated. The influence of film characteristics and pH of the medium on the permeability behavior of the films has been studied for a cationic dye, Azure B (AzrB). The results revealed pH sensitivity of the films towards swelling and solute transport. Based on the results, possible mechanisms of water and dye transport through the films have been proposed.     

稀土联合掺杂TiO2离子存储薄膜的制备及性能

以钛酸四丁酯、硝酸铈和硝酸钐为主要原料,采用溶胶-凝胶法在ITO导电玻璃基片表面制备了Ce,Sm掺杂摩尔分数为2%的Ti O2离子存储薄膜。采用XRD、SEM、循环伏安曲线、紫外-可见透射光谱等技术手段,研究了薄膜的结构、电化学性能和光学性能。结果表明,Ce,Sm掺杂Ti O2薄膜粒度均匀且颗粒细小,相比纯Ti O2薄膜具有更高的无定形程度。在电致变色反应过程中,Ce、Sm掺杂Ti O2薄膜离子存储能力强、循环可逆性好,注入电荷密度为15.12 m C·cm-2,K值为0.7。薄膜具有较好的光学透明度,不同外加电压下薄膜的透射率均在80%左右,可以在电致变色玻璃中作为离子存储材料。     

聚乙烯醇与海藻钠包埋固定化复合菌种降解焦化废水中氰化物的研究

用聚乙烯醇和海藻酸钠对复合菌种固定化,考察交联时间、菌胶比和PVA浓度对复合菌种降解氰化物的影响。结果表明,各因素对固定化复合菌种降解氰化物的影响次序为:菌胶比交联时间PVA;固定化复合菌种降解焦化废水中氰化物的优化降解工艺条件为:PVA溶液浓度6%,菌胶比为1∶15,交联时间为32 h,在此条件下氰化物的降解率为88.4%。