基于聚多巴胺的氮掺杂碳材料的制备及其电化学性能

多孔碳材料由于高的比表面积、优异的电子传导率、良好的化学稳定性等优点在超级电容器电极材料领域被广泛研究。 碳材料的组成及表面孔结构直接影响其电化学性能,为进一步提高碳材料的电容性能,本文首次以聚多巴胺球为前体,KOH为活化剂,通过高温碳化成功制备了良好电化学性能的氮掺杂多孔碳材料。 通过扫描电子显微镜(SEM)、透射电子显微镜(TEM)、 X射线粉末衍射(XRD)、傅里叶变换红外光谱(FT-IR)、X射线光电子能谱(XPS)和Raman光谱等对所制备的氮掺杂多孔碳材料进行了形貌及结构组成的表征。 在6 mol/L KOH电解液中, 采用循环伏安、恒电流充放电对多孔碳材料的电化学性能进行了研究。 结果表明,由于双电层电容和赝电容的协同作用,在电流密度为1 A/g时,材料的比电容可达269 F/g,充放电循环1000圈后电容仍可保留初始值的93.5%。     

杂多酸/聚苯胺/二氧化锰复合材料的制备及其电化学性能研究

使用磷钨酸(PW₁₂)为苯胺(AN)单体聚合提供酸环境,合成聚苯胺(PANI),通过原位聚合法制备出不同比例的PW₁₂/PANI/MnO₂复合材料。通过红外光谱(FT-IR)、X射线衍射(XRD)和扫描电镜(SEM)对复合材料电极材料的结构和形貌进行表征,利用电化学工作站测试复合材料的电化学性能。结果表明,制备出的复合材料呈现以下优点,例如明显的多孔结构,较大的比表面积,材料的团聚现象也得到了明显的改善,复合材料的比电容达到493.29 F/g左右,说明经过掺杂的复合材料的电化学性能相对于单一赝电容材料(聚苯胺,314.27 F/g)有了明显的提升,合成的三元纳米复合材料具有作为电极材料的潜力,可用于下一代高速率储能系统。     

不同掺杂酸对纤维聚苯胺电化学性能的影响

采用界面聚合法通过不同质子酸掺杂分别制备了平均直径约为50,62,95nm的纤维聚苯胺。通过傅里叶变换红外光谱(FT-IR)、扫描电子显微镜(SEM)、透射电镜(TEM)对其化学组成和微观形貌进行了表征,采用循环伏安、恒流充放电和交流阻抗研究了不同质子酸掺杂纤维聚苯胺的超级电容器电容行为,并利用X射线衍射(XRD)、氮气吸脱附及X射线光电子能谱(XPS)等方法对纤维聚苯胺的微观结构进行了深入研究。结果表明:高氯酸(HClO4)掺杂制备的聚苯胺在0.5A/g电流密度下的比容量可以达到397F/g,高于盐酸(HCl,334F/g)和樟脑磺酸(HCSA,383F/g)掺杂聚苯胺的测试结果,纤维的电化学性能主要受其规整度、孔隙率及掺杂度的影响。     

双离子液体基多孔炭的制备与电化学性能

以质子型离子液体1-氢-3-乙烯基咪唑硫酸氢盐(HVIm HSO₄)为主炭源,以1-丁基-3-甲基咪唑六氟磷酸盐(BMImPF₆)为助剂,在氮气气氛、1000℃下一步炭化得到氮、磷、硫共掺杂多孔炭.通过N₂吸附-脱附、扫描电子显微镜(SEM)、透射电子显微镜(TEM)、X射线衍射(XRD)、拉曼光谱(Raman)、热重分析(TGA)和X射线光电子能谱(XPS)等技术对多孔炭进行了分析表征.结果表明,多孔炭的孔结构以微孔为主,最高比表面积可达1111 m²/g,其微晶结构中无定形碳和石墨化碳并存;多孔炭中的氮主要以季氮(N-Q)、吡咯氮(N-5)和吡啶氮(N-6)的形式存在,磷以磷-氧(N—O—P)键合形式为主,硫主要以噻吩硫(C—S—C)为主.在6 mol/L KOH溶液、三电极体系中,多孔炭在0. 5 A/g电流密度下的比电容为138 F/g;在10 A/g电流密度下的比电容为100 F/g;在2 A/g电流密度下循环充放电10000次,其比电容保持率为95. 8%,显示出良好的电化学性能.     

酸功能化碳纳米管对多孔碳材料储能活性及稳定性的增强作用

采用球磨法将酸功能化碳纳米管（AMWCNTs）与环糊精均匀混合。 酸功能化有利于增强碳管和环糊精间的相互作用,从而使二者形成均匀、有效的复合。 在N2气保护下碳化并经后续的ZnCl2活化处理,最终获得酸功能化碳纳米管/多孔碳(PC)复合体材料。 采用透射电子显微镜、X射线衍射和拉曼光谱等方法对材料结构进行了表征。 结果表明,碳纳米管在多孔碳骨架内均匀分布,并且复合体同时具有较高的比表面积和良好的导电性。 循环伏安及恒流充放电等电化学测试表明,由于二者的协同作用及碳纳米管在多孔碳骨架内均匀、有效的复合,材料具有较好的电化学储能性能和良好的电化学稳定性。 电流密度为0.5 A/g时,AMWCNTs/PC12-4（其中12代表β-环糊精和AMWCNTs的质量比,4代表酸化碳纳米管/β-环糊精碳与氯化锌的质量比）复合材料的质量比电容为156 F/g,远远高于AMWCNTs（43 F/g）和PC-4（87 F/g）。 经5000次循环后,电极比电容无明显衰减,而且每次恒流充放电的库仑效率均大于99.9%,说明复合材料具有良好的稳定性,是非常有前景的超级电容器电极材料。     

氮掺杂石墨烯量子点/MOF衍生多孔碳纳米片构筑高性能超级电容器

首先采用溶液法在碳布上生长Co-MOF二维纳米片,通过高温退火和刻蚀后得到MOF衍生多孔碳纳米片。以Co-MOF衍生的多孔碳纳米片/碳布(CNS/CC)作为碳基骨架,采用电化学沉积法负载高活性氮掺杂石墨烯量子点(N-GQDs),制备得到分级多孔结构的N-GQD/CNS/CC复合材料。组装成自支撑且无粘结剂的N-GQD/CNS/CC电极,当电流密度为1 A·g~(-1)时,其比电容高达423 F·g~(-1)。通过储能机制和电容贡献机制的研究表明,在碳纤维上原位生长的具有高双电层电容的CNS和表面负载具有高赝电容的N-GQDs之间相互协同作用,使得N-GQD/CNS/CC电极具有高电容性能,是一种理想的超级电容器电极材料。电极材料的高导电、分级多孔结构有利于电子的传输和电解质离子的扩散,具有良好的动力学性能,能快速充放电和具有优异的倍率特性。将电极组装成对称型超级电容器,功率密度为250 W·kg~(-1)时对应的能量密度达到7.9 Wh·kg~(-1),且经过10 000次循环后电容保持率为91.2%,说明氮掺杂石墨烯量子点/MOF衍生多孔碳纳米片复合材料是一种电化学性能稳定的具有高电容性能的全碳电极材料。     

褐煤基多孔炭/CoNi2S4复合材料的制备及电容特性研究

以宝清褐煤为原料,使用KOH溶液萃取、活化后制得煤基多孔炭,并利用简单的水热法将褐煤基多孔碳与CoNi_2S_4复合,制备复合电容电极材料。考察了不同碳添加量对褐煤基多孔碳/CoNi_2S_4复合材料电化学性能的影响,结果表明,碳添加量过高或过低都不利于复合材料比电容的提升,而碳添加量为37%的褐煤基多孔碳/CoNi_2S_4复合材料具有较高的比电容和良好的循环性能,该复合电极在4 A/g电流密度下,比电容达到1318.2 F/g,在4000次充放电循环后电容保持率为80.9%。     

超高比表面积氮掺杂多孔碳材料的制备及其超级电容性能

以蔗糖为碳源、尿素为氮源、草酸钾为活化剂,通过简单的研磨和高温碳化制备了具有超高比表面积(大于3 000 m²·g^-1)的氮掺杂多孔碳材料。采用多种手段对多孔碳材料的微观形貌、比表面积、孔结构和表面氮物种进行了表征,探究了不同温度下草酸钾和尿素对碳材料的比表面积、氮含量和超级电容性能的影响。结果表明,仅使用草酸钾作为活化剂制备的碳材料KC-800的比表面积为1 114 m²·g^-1,而同时使用草酸钾和尿素制备的样品KNC-800的比表面积高达3 033 m²·g^-1。在以6.0mol·L^-1 KOH为电解液的三电极体系中,当电流密度为0.5 A·g^-1时,KNC-800的比电容为405 F·g^-1,而KC-800的比电容仅为248 F·g^-1。这表明草酸钾和尿素的加入显著提高了多孔碳材料的比表面积和超级电容性能。电容贡献分析表明,KNC-800的双电层电容值和赝电容值均...     

聚苯胺纳米刺/掺氮空心碳球复合材料的制备及电容性能

以掺氮空心碳球（N-HCS）为骨架,通过化学氧化聚合法制备了聚苯胺纳米刺/掺氮空心碳球复合材料（PANI/N-HCS）,采用扫描电子显微镜、透射电子显微镜和红外光谱仪等对样品的形貌、结构等进行了表征. 采用循环伏安、计时电位和交流阻抗等方法在1 mol/L H₂SO₄水溶液中考察了材料的电化学性能. 结果表明,PANI/N-HCS具有良好的电化学性能,在0.5 A/g电流密度下,PANI/N-HCS的比电容达346 F/g;当电流密度为20 A/g时,PANI/N-HCS比电容值为228 F/g,电容保持率为66%;在5 A/g电流密度下,经1000次充放电循环后,电容保持率为76%.     

快速混合法制备超级电容器用聚苯胺-活性炭复合材料

采用快速混合法制备聚苯胺-活性炭复合材料。通过扫描电镜、红外光谱等手段表征材料的形貌结构,通过恒流充放电、循环伏安和交流阻抗等技术测试了材料的电容特性。研究结果表明:制备的纯聚苯胺具有纳米纤维结构,但存在团聚问题;活性炭的加入抑制了纳米纤维之间的团聚,修饰了多孔形貌,降低了电荷传递阻抗,材料的功率特性得以改善,循环性能表现良好。当活性炭的用量为20%时,复合材料的比电容达371F/g,1 000次循环的比电容保持率为66.6%;电流密度由0.2A/g增加至1.5A/g,比电容下降小于5F/g。     

Cupressus arizonica fruit essential oil: A novel green inhibitor for acid corrosion of carbon steel

Natural-based corrosion inhibitors have gained great research interest thanks to their low cost and higher performance. The Cupressus arizonica fruit essential oil (CAFEO) has a higher extraction yield than leaves; however, it has less antibacterial and antifungal activities. The three main components in the CAFEO were α-pinene (51.07%), myrcene (17.92%), and limonene (9.66%). Essential oils with a higher percentage of α-pinene were found to have outstanding corrosion inhibition properties. Therefore, herein, the CAFEO was investigated as a green corrosion inhibitor for carbon steel (CS) in 1.0 mol/L HCl using electrochemical, i.e., potentiodynamic polarization (PDP) and electrochemical impedance spectroscopy (EIS), and scanning electron microscope (SEM) techniques. The experimental results revealed that CAFEO successfully inhibited the carbon steel corrosion in 1.0 mol/L HCl solution. Results from PDP indicated that the inhibitor had a mixed-type effect with a predominance cathodic character. EIS data showed that the charge transfer resistance of the CS electrode increased from 20.9 Ω cm² in blank solution to 294.5 Ω cm² in HCl solution inhibited with 0.5 g/L of CAFEO at 298 K, leading to a significant decrease in the double layer capacitance values and an inhibition efficiency (η%) of 93%. The high temperatures showed a negative effect on the corrosion inhibition efficiency of the tested inhibitor. At 323 K, the η% of CAFEO decreased to 77%. Besides, SEM images showed that the inhibitor formed a protective barrier against acid attack, preventing carbon steel from corrosion. Theoretical calculations by Density Functional Theory (DFT) were performed to investigate the reactivity of the three main components of CAFEO.     

Comprehensive utilization of dairy manure to produce glucose and hierarchical porous carbon for supercapacitors

Dairy manure, one of the most abundant agricultural wastes generated in livestock farming, was pretreated with KOH aqueous solution to relieve the constraint of lignin, thus facilitating cellulose hydrolysis. The generated black liquor waste was used to prepare porous carbon. Glucose yield of 261 g/kg was obtained from dairy manure pretreated in 0.73 wt% HCl aqueous solution, much higher than that obtained from crude dairy manure (116 g/kg). The generated black liquor, mainly containing lignin and KOH, was employed to prepare porous carbon via a self-templating method. The obtained material had a three-dimensional (3D) hierarchical structure and was applied for supercapacitors. Good capacitance of 202 F/g was obtained in a two-electrode system with 6 M KOH electrolyte. The porous carbon-based electrode showed excellent cycling stability with retention of 100% after 3000 galvanostatic charge–discharge (GCD) cycles. This work provides a scalable strategy for comprehensive utilization of lignocellulosic biomass resources.     

Synthesis of Poly(N-ethylaniline) Nanoparticles Synthesis and Characterization of Organically Soluble Conducting Poly(N-ethylaniline) Nanoparticles using Acrylic Acid as a Soft Template

In this paper, we report the synthesis of poly(N-ethylaniline) (PNETA) by using tartaric acid (TA) as an organic acid dopant by aqueous polymerization method of N-ethylaniline using ammonium per sulphate (APS) as an oxidant and acrylic acid (AA) as a soft template. This is a new polymerization method for the direct synthesis of the emeraldine salt form of poly(N-ethylaniline) in bulk quantity, which is soluble in organic solvents such as m-cresol and N-methyl pyrrolidinone. The prepared polymers were characterized by UV, FTIR, XRD, TGA, SEM and conductivity measurement studies. The results are discussed with reference to HCl doped poly(N-ethylaniline). It is observed that PNETA/TA/AA polymer is comparatively more soluble in m-cresol than that doped with HCl in its salt form. The formation of emeraldine salt phase and dopping process was confirmed by FTIR and UV-Vis spectroscropy. We demonstrate the effect of organic dopant on the morphology and conductivity of the PNETA. It was found that, PNETA doped with TA synthesized using acrylic acid (AA) as a soft template display higher doping level, crystallinity and solubility in common organic solvent. On the contrary, HCl doped polymer was lowered at doping level and amorphous in nature which reflects the role of organic dopant and soft template. X-ray diffraction studies indicate that the PNETA/TA/AA doped samples exhibit higher crystallinity, which indicates enhanced polymer sub-chain alignment as compared to HCl doped polymer. This is also manifested by the FTIR studies. SEM result also revealed the continuous morphology and sub-micrometer size, evenly distributed particles of the PNETA/TA/AA doped polymer.     

聚苯胺/聚砜复合材料的制备及其超级电容性能

通过化学聚合法,制备出盐酸掺杂聚苯胺（PANI）,将其与聚砜（PSF）溶液混合,定量滴加到玻碳电极上制得PANI/PSF复合膜电极。 采用扫描电子显微镜、红外光谱以及X射线衍射对其结构和形貌进行表征。 根据循环伏安曲线、恒电流充放电曲线和电化学阻抗,研究了其作为电极的超级电容性能。 结果表明,多孔结构的PANI/PSF复合材料具有良好的电容性能,其比电容可达到497 F/g,并且该超级电容器具有较小的内阻和较好的循环稳定性。     

季铵盐掺杂聚苯胺电极的电容性能

采用循环伏安法,在铂电极表面聚合制备了季铵盐[CnH2n+1N(CH3)3]Cl(n=12,14,16,18)掺杂的聚苯胺修饰电极。 利用扫描电子显微镜、红外光谱以及X射线衍射对复合电极的表面形貌和结构进行了表征。 用循环伏安法、交流阻抗和恒电流充放电测试对电极的电化学性质和电容行为进行了系统研究。 结果表明,其中[C18H37N(CH3)3]Cl季铵盐掺杂的聚苯胺复合电极比表面积大,电容性能好,在2×10-3 A的充电电流下,初始比电容高达329.6 F/g,未掺杂电极比电容为199.0 F/g。 而且,复合电极的循环稳定性良好,经30次循环后比电容保持为252.4 F/g。     

低温合成樟脑磺酸掺杂聚苯胺微管的电化学电容行为

在低温条件下合成了长约为2-3 μm, 外径约为300-400 nm 的樟脑磺酸掺杂聚苯胺微管. 扫描电镜(SEM)和透射电镜(TEM)显示, 生成的聚苯胺微管管径受樟脑磺酸浓度的影响, 高浓度的掺杂剂有利于管状聚苯胺的形成. 采用交流阻抗、循环伏安、恒流充放电等测试技术对不同产物的电化学电容行为进行了研究, 结果表明, 苯胺单体与樟脑磺酸的摩尔比为1:1时所得掺杂态聚苯胺电极具有较好的循环稳定性, 单电极比电容达到522 F·g-1.     

锂离子电池正极材料LiNi 0.5Co 0.2Mn 0.3O2和LiNi 0.5Co 0.2Mn 0.3O2/LiFePO4容量衰减原因分析

采用湿法球磨法制备了锂离子电池混合正极材料LiNi _0.5Co _0.2Mn _0.3O₂/LiFePO₄ (NMC532/LFP). 通过X射线衍射(XRD)、扫描电子显微镜(SEM)、充放电测试和电化学阻抗谱测试(EIS)等方法研究对比了LiNi _0.5Co _0.2Mn _0.3O₂(NMC532)和LiNi _0.5Co _0.2Mn _0.3O₂/LiFePO₄ (NMC532/LFP)的容量衰减机理,结果表明：循环50次和60℃高温存储后,NMC532/LFP的容量保持率分别为97.80%、86.48%,其循环和高温存储性能较好. 循环和高温存储后NMC532和NMC532/LFP的电荷传递阻抗Rct明显增大,但NMC532/LFP的Rct较小. NMC532和NMC532/LFP的I(003)/I(104)值都有所减小,但NMC532/LFP的I(003)/I(104)值比NMC532的大,即NMC532/LFP材料的阳离子混排现象有所改善. 循环后NMC532、NMC532/LFP颗粒没有出现明显的表面开裂和链接断裂现象,但NMC532颗粒有部分发生粉化. 高温储存后NMC532颗粒表面出现裂纹,且颗粒之间的链接断裂,NMC532/LFP颗粒表面出现轻微粉化. 材料结构规整度下降,阳离子混排程度加剧,电荷传递阻抗增大是NMC532和NMC532/LFP容量衰减的主要原因.     

Soluble conductive polypyrrole synthesized by in situ doping with β-naphthalene sulphonic acid

Soluble polypyrrole (PPy) with high conductivity (27 S/cm) has been prepared by chemical polymerization of pyrrol monomer in the presence of β-naphthalene sulphonic acid (NSA) as a dopant. The solubility of the resulting conducting polymer of PPy-NSA in m-cresol increases with increasing the concentration of NSA in the polymerization media, and the highest solubility of PPy-NSA in m-cresol is about 1.2 g/100 mL. The room-temperature conductivity of PPy-NSA significantly increases with the concentration of NSA when the concentration of NSA is less than 0.1 mol/L, while it slightly decreases with increasing the concentration of NSA after the concentration of NSA is higher than 0.1 mol/L. UV-VIS spectra and ESR measurements demonstrate that both polaron and bipolaron are present as a charge carrier. The resulting PPy-NSA exhibits unusual fibrillar morphology with a diameter of about 0.5 μm, which is quite different from the granular morphology of PPy doped with dodecyl benzene sulfonic acid (DBSA) and HCl. Moreover, the polymerization conditions greatly influence the morphology of the obtained PPy-NSA. © 1997 John Wiley & Sons, Inc. J Polym Sci A: Polym Chem 35: 3689–3695, 1997     

静电纺氧化锰复合碳纳米纤维柔性膜的电化学性能

采用一步法静电纺丝技术制备了具有超亲水特性的氧化锰/碳纳米纤维(MnO_x/CNFs)复合柔性膜电极材料,并通过X射线衍射、扫描电子显微镜和透射电子显微镜等对复合材料进行了表征.电化学性能测试结果表明,复合材料的电容性能优于单一材料,醋酸锰质量分数为40%时制得的复合纳米纤维电极(MC-4)在1 A/g电流密度下,于2 mol/L KOH电解液中的比电容高达1112.5 F/g,10 A/g电流密度下循环3000次比容量保持在93.4%,具有很好的稳定性.MnO_x/CNFs复合材料电化学性能增强一方面是由于三维超亲水纤维膜结构有利于电解液的快速浸润渗透,从而极大缩短了传输到材料基质的有效路径;另一方面是由于碳和MnO_x的协同效应,包裹在MnO_x粒子周围的碳层避免了MnO_x在充放电过程中的体积膨胀效应,这2种叠加机制促进了电化学性能的提升.     

Facile Synthesis of Nitrogen‐Doped Graphene Aerogels for Electrode Materials in Supercapacitors

Three‐dimensional porous nitrogen‐doped graphene aerogels (NGAs ) were synthesized by using graphene oxide (GO ) and chitosan (CS ) via a self‐assembly process by one‐pot hydrothermal method. The morphology and structure of the as‐prepared materials were characterized by means of scanning electron microscopy, transmission electron microscopy, X‐ray diffraction, XPS spectroscopy, Raman spectroscopy, nitrogen adsorption/desorption measurement and Fourier transform infrared spectroscopy. The electrochemical performance of NGAs was studied by cyclic voltammetry, galvanostatic charge/discharge and impedance spectroscopy measurements. The microstructure, surface area and capacitance of NGAs could be facilely controlled by adding different amounts of chitosan. The prepared NGA ‐4 showed a specific capacitance of 148.0 F/g at the discharge current density of 0.5 A/g and also retained 95.3% of the initial capacitance after 5000 cycles at the scan rate of 10 mV /s. It provided a possible way to obtain graphene based materials with high surface area and capacitance.