电化学混合电容器用新型β-Ni(OH)2/CNTs纳米复合物

采用水热合成法制备出一种新型β-Ni(OH)₂/碳纳米管(CNTs)纳米复合物, Ni(OH)₂微晶粒径控制在50～80 nm之间, 与CNTs直径相当, CNTs与Ni(OH)₂质量比为1∶15. 将纳米复合物应用于活性炭(AC)/NiOOH电化学混合电容器, 电化学测试表明: 在0.4 A/g电流条件下, 其放电比容量达279 mAh/g, 是β-Ni(OH)₂理论容量的96.5%; 当电流密度从0.4 A/g增加至8 A/g时, 电容器的容量保持率在76.5%以上, 高倍率充放电特性优异. 此外, 纳米复合物良好的电化学可逆性使AC/NiOOH电化学混合电容器更易活化, 并具有较高的充放电效率和良好的循环稳定性能.     

[Ni(phen)2(3,5-DMBA)](m-MBA)2(H2O)2配合物的合成、晶体结构及电化学分析

The title complex of nickel (II) with 3,5-dimethylbenzoic acid, m-methylbenzoic acid and 1,10- phenanthroline was synthesized and characterized. Crystal data for this complex: triclinic, space group P1, a=1.198 5(2) nm, b=1.315 3(2) nm, c=1.531 8(3) nm, α=92.602(3)°, β=103.292(3)°, γ=114.849(3)°, V=2.104 7(6) nm³, D_c=1.361 g·cm^-3, Z=2, F(000)=902, final GooF=1.071, R₁=0.067 2, wR₂=0.155 5. The crystal structure shows that the nickel ion is coordinated with four nitrogen atoms of two 1,10-phenanthroline molecules and two oxygen atoms of one 3,5-dimethyl benzoic acid molecule, forming a distorted octahedral coordination geometry. The cyclic voltametric behavior of the complex was also investigated. CCDC: 286966.     

配合物[Ni(phen)3][(C6H5)2C(OH)COO]2·6H2O的合成、晶体结构及电化学性质

The title complex with benzilic acid and 1,10-phenanthroline monohydrate has been synthesized and characterized in the solvent mixture of water and methyl-alcohol. It falls into the triclinic, characteristic of the space group P1 with a=1.142 8(3) nm, b=1.638 8(4) nm, c=1.645 6(4) nm, α=74.428(5)°, β=84.205(5)°, γ=74.917(5)°, V=2.864 9(12) nm³, D_c=1.347 g·cm^-3. Z=2, F(000)=1 216, the reliability factor R₁=0.068 9, wR₂=0.189 9. The crystal structure shows that the nickel atom is coordinated with six nitrogen atoms from the three phens, forming a distorted octahedral coordination geometry. The cyclic voltametric behavior of the complex is also reported. CCDC: 274184.     

泡沫镍载Co（OH）2纳米线的电化学电容性能

以无模板法制备了泡沫镍载Co(OH)2纳米线电极,利用扫描电镜(SEM)和透射电镜(TEM)观测了纳米线的表面形貌,利用X射线衍射(XRD)分析了Co(OH)2纳米线的结构,通过循环伏安、恒流充放电和交流阻抗测试了电极的电化学电容性能.结果表明:Co(OH)2呈线状生长,其直径约为300nm,长度约为8～10μm,密集地生长在泡沫镍骨架上.电流密度为10mA·cm-2时电极的放电比容量高达677F·g-1,循环500次后比容量仍保持在574F·g-1,电化学阻抗测试其电荷传递电阻仅为0.23Ω,500次循环后电荷传递电阻仅增加0.03Ω.     

纳米级β-Ni(OH)2掺杂Al(OH)3的电化学性能

钠米粉体;纳米级β-Ni(OH)2掺杂Al(OH)3的电化学性能     

包覆Y(OH)3的球形Ni(OH)2的电化学性能

利用软嵌式粉末电极技术研究了Y(OH)3包覆对球形Ni(OH)2电化学性能的影响. 循环伏安结果表明, 在球形Ni(OH)2的氧化过程中存在Ni(Ⅲ)和Ni(Ⅳ)的两步氧化反应, 产生的Ni(Ⅳ)不稳定, 能分解产生NiOOH和氧气, 所以可将Ni(Ⅲ)→Ni(Ⅳ)看作副反应. Y(OH)3包覆层对Ni(OH)2氧化过程后期的副反应, 特别是Ni(Ⅲ)→Ni(Ⅳ)具有较好的抑制作用. 由包覆后的Ni(OH)2制成的模拟电池表现出很好的高温性能, 在1C充放电条件下, 当Y的摩尔分数为1.61%时, 在60 ℃时所对应的容量保持率可达到25 ℃的92.7％; 当Y的摩尔分数仅为0.55 %时, 在60 ℃时所对应的质量比容量也可达到241.3 mA·h/g.     

Y(PO3)3双包覆改性对Li[Ni0.8Co0.15Al0.05]O2电化学性能的影响

在镍钴铝酸锂正极材料 Li[Ni_0.8Co_0.15Al_0.05]O₂(NCA)制备过程中表面遗留的碱性物质会严重影响其循环稳定性能,针对这一难题,提出使用Y(PO₃)₃对其进行表面包覆改性,利用Y(PO₃)₃与表面残留的LiOH反应消除表面残碱,并探讨包覆改性对NCA整体性能的影响机制。测试分析结果表明,在低温煅烧过程中前驱体表面会形成均匀致密的Y(PO₃)₃和LiPO₃包覆层,LiPO₃有较高的离子电导率,双包覆层能够防止活性物质在电化学循环过程中与电解液相互接触时发生有害副反应,提高电极材料的循环稳定性。其中Y(PO₃)₃包覆量(质量分数)为1%的样品在0.1C下的首次库仑效率从未改性样品的78.65%提高到88.50%,在1C下循环150圈后容量保持率从59.38%提高到85.33%,相比于未改性样品具有更高的首次库仑效率和更优异的循环性能。     

Y(PO3)3双包覆改性对Li[Ni0.8Co0.15Al0.05]O2电化学性能的影响

在镍钴铝酸锂正极材料 Li[Ni_0.8Co_0.15Al_0.05]O₂(NCA)制备过程中表面遗留的碱性物质会严重影响其循环稳定性能,针对这一难题,提出使用Y(PO₃)₃对其进行表面包覆改性,利用Y(PO₃)₃与表面残留的LiOH反应消除表面残碱,并探讨包覆改性对NCA整体性能的影响机制。测试分析结果表明,在低温煅烧过程中前驱体表面会形成均匀致密的Y(PO₃)₃和LiPO₃包覆层,LiPO₃有较高的离子电导率,双包覆层能够防止活性物质在电化学循环过程中与电解液相互接触时发生有害副反应,提高电极材料的循环稳定性。其中Y(PO₃)₃包覆量(质量分数)为1%的样品在0.1C下的首次库仑效率从未改性样品的78.65%提高到88.50%,在1C下循环150圈后容量保持率从59.38%提高到85.33%,相比于未改性样品具有更高的首次库仑效率和更优异的循环性能。     

洗涤时pH值对纳米级β-Ni(OH)2的团聚程度和电化学性能的影响

Nano-scale nickel hydroxide was prepared by precipitate transformation method in the paper. Effect of rinse pH on the agglomeration degree and electrochemical performance of nano-scale Ni(OH)₂ was investigated. The mea-surement results of XRD and TEM indicate that the prepared nano-scale Ni(OH)₂ is β(Ⅱ)-phase,the grain size is in the rang of 10～50nm,and rinse pH exerts a great influence on the agglomeration degree of nano-scale Ni(OH)₂. The agglomeration of material becomes very obvious when rinse pH=11, and the density of nano-scale Ni(OH)₂ is enhanced obviously.Cyclic voltammetry(CV) and simulate cells experiment show that nano-scale Ni(OH)₂ with suitable agglomeration degree have better electrochemical CV performance than those with ideal disperse Ni(OH)₂ and micron Ni(OH)₂, and its proton diffusion coefficient is also the highest. It can elevate the discharge potential platform and prolongs discharge time, so the utilization ratio of Ni(OH)₂ is raised.     

铝代α-Co（OH）2的制备及其电化学性能

采用化学共沉淀方法制备了Co-Al双金属氢氧化物,用红外光谱对所制样品的成分进行分析;用X射线衍射和场发射扫描电子显微镜表征产物的结构和形貌;用循环伏安、恒电流充放电等测试方法对Co/Al摩尔比为9∶1、8∶2和7∶3的铝代α-Co(OH)2的电化学性能进行研究。测试表明,Co/Al摩尔比为8∶2的铝代α-Co(OH)2具有最佳的电容性能,单电极比电容可达1180F/g,并且在1A/g电流密度下循环500周后,比电容仍能保持91%,有望成为电化学电容器的电极材料。     

Ni（OH）2超微粉的制备及其电化学性能

用沉淀转化法制备了Ｎｉ（ＯＨ）２超微粉，并以微米级球形Ｎｉ（ＯＨ）２作对照，用循环伏安法和电化学阻抗谱研究其电化学性能，发现Ｎｉ（ＯＨ）２超微粉有更好的电化学性能     

碱性蓄电池正极用球形微粒Ni（OH）2的制备,性能和结构

碱性蓄电池正极用球形微粒Ｎｉ（ＯＨ）２的制备、性能和结构赵林治＊杨书廷赵培正吕庆章丁立张明春（河南师范大学化学系新乡４５３００２）关键词Ｎｉ（ＯＨ）２，球形微粒，制备，性能，结构，氢氧化镍电极１９９７－０６－１６收稿，１９９７－１１－１７修回国家自然...     

圆盘状a-Co(OH)2的控制合成及其电化学性能

采用AAO模板及后处理方法合成了圆盘状a-Co(OH)2并研究了其电化学电容性能.在该合成方法中,先采用阳极氧化铝模板结合交流电沉积的方法获得钴纳米线,而后将其在碱液中通过溶解氧氧化生成终端产物.用红外光谱(FT-IR),X射线衍射(XRD)和场发射扫描电子显微镜(FE-SEM)表征了产物的结构和形貌;用循环伏安、恒电流充放电测试方法对其电化学性能进行了测试.此外,对圆盘状Co(OH)2的形成机理进行了初步探讨.结果表明,用此方法合成的Co(OH)2具有圆盘状形貌,属a相态,且表现出较好的电容特性.     

共沉积铝镍氢氧化物的结构及电化学特性

为了改善Ni(OH)2的电化学性质,提高锌镍电池的充放电性能,用化学共沉淀法合成了混合铝镍氢氧化物Ni/Al(OH)x.用XRD和FTIR表征了Ni/Al(OH)x样品的晶体结构及IR光谱特征;测试了用Ni/Al(OH)x为正极活性物质的Zn/Ni实验电池的充放电性能.研究结果表明:所合成的Ni/Al(OH)x具有α-Ni(OH)2的晶体结构;Ni/Al(OH)x活性物质在充放电过程中主要为γ/α循环,以Ni/Al(OH)x作为正极活性物质的Zn/Ni试验电池具有优良的循环性能,其最高放电比容量为379mA·h/g.     

Co(OH)_2和Ni粉对氢氧化镍电极性能的影响

采用三角波电位扫描、X射线衍射及恒流充放电曲线法研究了在氢氧化镍电极中添加Co( OH) 2 和 Ni粉后对电极性能的影响 .结果表明 ,氢氧化镍电极中加入质量分数为 8% Co( OH) 2和 13% Ni粉时 ,电极的放电容量最高 ,电极在充放电循环过程中的膨胀最小 .     

表面覆CoOOH的球形Ni(OH)2的制备及快充性能

应用化学沉淀-电化学氧化法,于球形N i(OH)2颗粒表面生成CoOOH包覆层,研究包覆处理对AA型高容MH/N i电池快充性能的影响,并由红外光谱和扫描电镜表征覆钴样品.结果表明,以包覆CoOOH的N i(OH)2作正极活性材料装配的电池较之于正极单一添加CoO的电池,其内阻降低了约3.4 mΩ,该电池快充时充电电压平台较低且在充电末期电池温度不超过55℃,首次放电效率达90.6%,快充循环寿命达300周次.     

钴的表面修饰对Ni(OH)2电极性能的影响

钴添加剂;钴的表面修饰对Ni(OH)2电极性能的影响     

Kristallstrukturen und Wasserstoffbrückenbindungen bei β-Be(OH)2 und ϵ-Zn(OH)2

Crystal Structures and Hydrogen Bonding for β-Be(OH)₂ and ϵ-Zn(OH)₂ Crystals of β-Be(OH)₂ sufficient for x-ray structure determination were grown from a saturated hot solution of freshly prepared Be(OH)₂ in NaOH by slowly cooling down and in the case of ϵ-Zn(OH)₂ by electrochemical oxidation of zinc in a NaOH/NH₃ solution. The structures of the isotypic compounds were determined including the H-positions: β-Be(OH)₂: P2₁2₁2₁, Z = 4, a = 4.530(2) Å, b = 4.621(2) Å, c = 7.048(2) Å N(F > 3σ F) = 432, N(parameters) = 36, R/R_w = 0.044/0.052 ϵ-Zn(OH)₂: P2₁2₁2₁, Z = 4, a = 4.905(3) Å, b = 5.143(4) Å, c = 8.473(2) Å N(F > 3σ F) = 1107, N(parameters) = 36, R/R_w = 0.025/0.027For neutron diffraction experiments microcrystalline β-Be(OD)₂ was prepared. With time-of-flight data the D positions were determined giving d(O–D) = 0.954(4) Å. The structures are closely related to that of β-cristobalite: As in SiO₂ a quarter of tetrahedral interstices in a distorted cubic close packed arrangement of O is regularily occupied by the metal atoms. The filled O tetrahedra are twisted against one another in such a way, that O–H…O–H hydrogen bonds are favoured which are surprisingly stronger in the zinc than in the beryllium compound.     

Bioinspired Peony‐Like β‐Ni(OH)2 Nanostructures with Enhanced Electrochemical Activity and Superhydrophobicity

Constructing complex nanostructures has become increasingly important in the development of hydrogen storage, self‐cleaning materials, and the formation of chiral branched nanowires. Several approaches have been developed to generate complex nanostructures, which have led to novel applications. Combining biology and nanotechnology through the utilization of biomolecules to chemically template the growth of complex nanostructures during synthesis has aroused great interest. Herein, we use a biomolecule‐assisted hydrothermal method to synthesize β‐phase Ni(OH)₂ peony‐like complex nanostructures with second‐order structure nanoplate structure. The novel β‐Ni(OH)₂ nanostructures exhibit high‐power Ni/MH battery performance, close to the theoretical capacity of Ni(OH)₂, as well as controlled wetting behavior. We demonstrate that this bioinspired route to generate a complex nanostructure has applications in environmental protection and green secondary cells. This approach opens up opportunities for the synthesis and potential applications of new kinds of nanostructures.