TiN基IrO2-Ta2O5涂层析氢电极的催化性能

 采用热分解法制备了以离子镀TiN膜为基体的IrO2-Ta2O5涂层电极,通过循环极化曲线并结合扫描电镜、 X射线能谱和X射线衍射研究了涂层的析氢电催化性能. 结果表明,涂层呈多孔多裂纹的结构,焙烧温度对涂层的表面形貌和电催化活性影响很大. 420 ℃下焙烧的涂层具有最优的电催化活性. 涂层电极的析氢反应电极电位为-0.26 V(vs SCE), 低析氢过电位下的Tafel斜率为-0.04 V, 而在高析氢过电位下,电极表面吸附的大量氢原子改变了氧化物电极的结构,从而抑制了氧的阴极还原反应.     

草酸在Ti/IrO2-Ta2O5阳极圆柱形电解槽中的电催化氧化降解动力学

从电催化氧化降解有机污染物的机理出发,研究了草酸在Ti/IrO2-Ta2O5阳极圆柱形电解槽中的电催化氧化过程,建立了描述整个降解过程的瞬时电流效率与溶液本体有机物浓度的关系式. 通过实验对模型进行了验证,实验结果与模型计算结果基本一致,并讨论了误差产生的原因.     

基于CH3NH3PbI3单晶的Ta2O5顶栅双极性场效应晶体管

Organic-inorganic hybrid perovskite methylammonium lead iodide (CH₃NH₃PbI₃) generally tends to show n-type semiconductor properties. In this work, a field-effect transistor (FET) device based on a CH₃NH₃PbI₃ single crystal with tantalum pentoxide (Ta₂O₅) as the top gate dielectric was fabricated. The p-type field-effect transport properties of the device were observed in the dark. The hole mobility of the device extracted from transfer characteristics in the dark was 8.7×10^-5 cm²·V^-1·s^-1, which is one order of magnitude higher than that of polycrystalline FETs with SiO₂ as the bottom gate dielectric. In addition, the effect of light illumination on the CH₃NH₃PbI₃ single-crystal FET was studied. Light illumination strongly influenced the field effect of the device because of the intense photoelectric response of the CH₃NH₃PbI₃ single crystal. Different from a CH₃NH₃PbI₃ polycrystalline FET with a bottom gate dielectric, even with the top gate dielectric shielding, light illumination of 5.00 mW·cm^-2 caused the hole current to increase by one order of magnitude compared with that in the dark (V_GS (gate-source voltage)=V_DS (drain-source voltage)=20 V) and the photoresponsivity reached 2.5 A·W^-1. The introduction of Ta₂O₅ as the top gate dielectric selectively enhanced hole transport in the single-crystal FET, indicating that in the absence of external factors, by appropriate device design, CH₃NH₃PbI₃ also has potential for use in ambipolar transistors.     

合金元素Nd对Pb-Ag阳极在H2SO4溶液中电化学行为的影响

采用循环伏安、线性扫描、电化学阻抗和环境扫描电镜对比研究了Pb-Ag和Pb-Ag-Nd阳极的阳极膜和析氧反应. 结果表明,合金元素Nd促进了Pb/PbO_n/PbSO₄ (1≤n<2)膜层的生长. 在高极化电位区间(高于1.20V (vs Hg/Hg₂SO₄/饱和K₂SO₄溶液)),Nd有利于低价铅的化合物(PbO_n,PbSO₄)向α-PbO₂和β-PbO₂转变. 此外,环境扫描电镜形貌和线性扫描分析证明Pb-Ag-Nd表面生成的阳极膜较Pb-Ag的阳极膜更厚且更致密. 因此,Pb-Ag-Nd阳极表面的阳极膜可以给合金基底提供更好的保护. 另一方面,电化学阻抗测试揭示了两种阳极的析氧反应均受中间产物的形成和吸附控制. Nd可以降低阳极膜/电解液界面处中间产物的吸附阻抗且增加中间产物的覆盖率,从而提高析氧反应活性. 综上所述,合金元素Nd可提高Pb-Ag阳极的耐腐蚀性,降低阳极电位进而起到节能降耗的作用.     

ZnFe2O4基惰性阳极在微型槽铝电解中的腐蚀行为

在960℃下,改变电解质分子比、阳极电流密度、电解质中氧化铝浓度,对ZnFe2O4基惰性阳极材料在微型槽铝电解中的腐蚀行为进行了考察.实验证明ZnFe2O4基阳极材料在电解过程中的腐蚀,随电解质中氧化铝浓度的升高、阳极电流密度的提高、电解质分子比的降低而减少.当电解质中氧化铝达到饱和时,在足够高的电流密度下,腐蚀趋向于一个最低值.     

新型锂盐LiBC2O4F2在EC＋DMC溶剂中的电化学行为

采用差热-热重(TG-DTA)、恒电流充放电和交流阻抗(EIS)分析了二氟草酸硼酸锂(LiODFB)的热稳定性,研究了LiODFB/碳酸乙烯酯(EC)+碳酸二甲酯(DMC)电解液的电化学性能及界而特征.实验结果表明,LiODFB不仅具有更高的热稳定性,而且在EC+DMC溶剂中具有较好的电化学性能.与使用LiPF6/EC+DMC的电解液相比,锂离子电池应用LiODFB基电解液在55℃的高温具有更好的容量保持能力;以0.5C、1C(1C=250 mA·g-1)倍率循环放电,两种电池间的倍率性能差别较小;LiODFB能够在1.5 V(vs Li/Li+)左右在石墨电极表面还原形成一个优异稳定的保护性固体电解质相界面膜(SEI膜);交流阻抗表明,使用LiODFB基电解液的锂离子电池仅具有稍微增加的界面阻抗.因此LiODFB是一种非常有希望替代LiPF6用作锂离子电池的新盐.     

Li2Mg2Si4O10F2、H2Mn8O16·1.4H2O和Li1.3Ti1.7Al0.3(PO4)3在高浓度LiCl水溶液中的离子交换行为

研究了用功能材料 Li2Mg2Si4O10F2(LHT)、 H2Mn8O16@ 1.4H2O(CRYMO)和 Li1.3Ti1.7Al0.3(PO4)3(LTAP)分别去除高浓度氯化锂水溶液中的杂质 Fe3+、 K+和 Na+ .实验结果表明,这几种功能材料分别对溶液中的杂质 Fe3+、 K+和 Na+有很高的选择性,除杂效果明显 .分析和研究了这几种功能材料在高浓度氯化锂水溶液中分别与 Fe3+、 K+和 Na+的交换行为 .结果表明,在高浓度氯化锂溶液中这几种功能材料与杂质交换的动力学行为可近似用 JMAK方程描述.     

Li2Mg2Si4O10F2、H2Mn8O16•1.4H2O和Li1.3Ti1.7Al0.3(PO4)3在高浓度LiCl水溶液中的离子交换行为

研究了用功能材料Li2Mg2Si4O10F2 (LHT)、H2Mn8O16•1.4H2O (CRYMO)和Li1.3Ti1.7Al0.3(PO4)3 (LTAP)分别去除高浓度氯化锂水溶液中的杂质Fe3＋、K＋和Na＋.实验结果表明，这几种功能材料分别对溶液中的杂质Fe3＋、K＋和Na＋有很高的选择性，除杂效果明显.分析和研究了这几种功能材料在高浓度氯化锂水溶液中分别与Fe3＋、K＋和Na＋的交换行为.结果表明，在高浓度氯化锂溶液中这几种功能材料与杂质交换的动力学行为可近似用JMAK方程描述.     

长链烷胺及手性钛的螯合物Ti[(OC2H4)3N][OCH(CH3)2]在层状V2O5中的插层行为

用一种简便快速方法合成了一系列长链有机胺插层V₂O₅化合物. 用粉末X射线衍射(XRD)、红外光谱(FT-IR)、漫反射紫外-可见光谱(DR UV-VIS)等手段对插层产品的结构进行了表征. 除了正十六胺插层V₂O₅产品外, 其它长链烷胺插层V₂O₅产品的层间距d₀₀₁与长链烷胺碳数n之间具有良好的线性关系: d₀₀₁＝0.160n_C＋0.731 nm. 正十六胺与V₂O₅反应后生成两个插层相, 一个相的层间距d₀₀₁为4.01 nm, 另一相的d₀₀₁为3.20 nm. 此外, 研究了手性钛的螯合物Ti[(OC₂H₄)₃N][OCH(CH₃)₂] (记为TEAIP)在V₂O₅层间的插层行为, 得到相应的插层产品.     

长链烷胺及手性钛的螯合物Ti[(OC2H4)3N][OCH(CH3)2]在层状V2O5中的插层行为

用一种简便快速方法合成了一系列长链有机胺插层V₂O₅化合物. 用粉末X射线衍射(XRD)、红外光谱(FT-IR)、漫反射紫外-可见光谱(DR UV-VIS)等手段对插层产品的结构进行了表征. 除了正十六胺插层V₂O₅产品外, 其它长链烷胺插层V₂O₅产品的层间距d₀₀₁与长链烷胺碳数n之间具有良好的线性关系: d₀₀₁＝0.160n_C＋0.731 nm. 正十六胺与V₂O₅反应后生成两个插层相, 一个相的层间距d₀₀₁为4.01 nm, 另一相的d₀₀₁为3.20 nm. 此外, 研究了手性钛的螯合物Ti[(OC₂H₄)₃N][OCH(CH₃)₂] (记为TEAIP)在V₂O₅层间的插层行为, 得到相应的插层产品.     

复合光催化材料H3PW122O40/Ta2O5光催化降解染料的研究

采用溶胶-凝胶法制备了半导体型金属氧化物Ta2O5,并通过浸渍法与杂多酸H,PW12O40复合,获得了纳米复合光催化材料H3PW12O40/Ta2O5.通过1CP-AES、FT-lR、N2吸附、Tc等手段对其组成、结构及其表面物理化学性质进行了表征,并在可见光下考察了该复合材料对可溶性染料罗丹明B和亚甲基蓝的光催化活性.实验结果表明,该复合材料存可见光下有较好的光催化活性,其中,H3PW12O40/Ta2O5在180min内对亚甲基蓝的光催化降解转化率达到78%.     

Ti/IrO2-Ta2O5阳极载量与析氧电催化性能研究

采用Pechini法制得Ti/IrO2-Ta2O5氧化物阳极,研究了涂层载量对Ti/IrO2-Ta2O5阳极微观结构和析氧电催化性能的影响.SEM、EDX、极化曲线、循环伏安及强化电解试验等测试结果表明:涂层载量增加,涂层裂缝变窄变浅,且IrO2晶粒偏析趋于增强;同时也提高了阳极析氧电催化活性,增大阳极活性表面积及延长阳极使用寿命;强化电解寿命与Ir涂覆量(1.98～9.08g/m2)基本呈线性递增关系.     

Ta 5+掺杂Li7La3Zr2O12的合成及其性能研究

本文采用固相法制备了Ta ⁵⁺掺杂的石榴石型无机固体电解质Li_7-xLa₃Zr_2-xO₁₂（xTa-LLZO）,研究了不同的掺杂量对材料性能的影响. 通过X射线发射光谱（XRD）、冷场发射电子扫描电镜（FESEM）和电化学阻抗（EIS）对材料进行物理表征和阻抗测试,并且组装LiFePO₄//LLZTO//Li全固态锂电池测试电池的循环稳定性. 结果表明,随着Ta ⁵⁺掺杂的增加,材料呈现出一个单一的立方相结构,当Ta ⁵⁺掺杂量为14.09wt.%（即x=0.3）时,材料的室温离子电导率达到最大（2.58×10 ^-4 S·cm ^-1）,呈现出稳定的立方相结构且具有相对较高的致密度（89.16%）,并具有较稳定的循环稳定性,经过50个循环后容量保持率依然保持到88.67%左右.     

Fabrication of Nb2O5/Carbon Submicrostructures for Advanced Lithium-Ion Battery Anodes

Nb₂O₅ possesses superior fast Li⁺ storage capability for LIB anodes, benefiting from its fast pseudocapacitive behavior and low volumetric change within the cycling processes. However, the poor electric conductivity for Nb₂O₅ restricts its reaction kinetics and rate property. Herein, Nb₂O₅/carbon (C) submicrostructures are fabricated by solvothermal method followed by calcination process. The Nb₂O₅/C submicrostructures exhibit outstanding rate behavior and cyclic performance (332 (194) mAh g⁻¹ after 1000 cycles at 1 (5) A g⁻¹). The superior electrochemical property is attributed to the distinctive structure for Nb₂O₅/C submicrostructures, in which Nb₂O₅ nanoparticles uniformly distributed within Nb₂O₅/C composite can protect Nb₂O₅ nanoparticles from agglomeration, and the porous carbon matrix can enhance electron/ion conductivity. This work furnishes a novel strategy for fabricating Nb₂O₅/C submicrostructures with superior Li⁺ storage performance, which can be potentially used to design other metal oxide/C submicrostructures for second battery anode.     

Ta/Al-Fe2O3薄膜电极的制备及其光电催化降解亚甲基蓝性能

采用简单的涂滴法制备出新型的Al、Ta 共掺杂的三元铁氧化物(Ta/Al-Fe₂O₃)可见光响应型光催化薄膜. 运用X射线光电子能谱(XPS)和紫外-可见(UV-Vis)光谱等手段对其进行了表征, 考察了其光电化学性能, 并研究了复合电极光电催化降解亚甲基蓝(MB)废水的反应性能. 由表面谱学分析可知, Ta 和Al 成功掺入Fe₂O₃中, Ta 会改变催化剂表面Al 和O的化学环境. 在可见光照射下的光电催化(PEC)反应中, Ta/Al-Fe₂O₃降解MB的反应速率约为Al-Fe₂O₃的2 倍, 光电催化共作用的效果优于单纯光催化作用(PC)和电催化(EC)作用的效果.结果表明, Ta掺杂有利于提高Ta/Al-Fe₂O₃薄膜的光电催化活性.     

A Newly Competitive Electrochemical Sensor for Sensitive Determination of Chrysin Based on Electrochemically Activated Ta2O5 Particles Modified Carbon Paste Electrode

A novel electrochemically activated doped Ta₂O₅ particles modified carbon paste electrode (EA‐Ta₂O₅‐CPE) was prepared and applied for selective and sensitive determination of chrysin. X‐ray diffraction (XRD), scanning electron microscopy (SEM), electrochemical impedance spectroscopy (EIS) techniques and cyclic voltammetry (CV) were used to characterize the Ta₂O₅ particles and investigate the electrochemical response of the sensor. Compared with bare CPE, the doped Ta₂O₅ modified electrode got much more porous by electrochemical treatment and exhibited larger effective surface area, more reactive site and excellent electrochemical catalytic activity toward the oxidation of chrysin. Under optimum conditions by LSV, the oxidation peak currents responded to chrysin linearly over a concentration range from 5.0×10⁻⁸ to 7.0×10⁻⁶ mol L⁻¹ with a detection limit of 2.0×10⁻⁸ mol L⁻¹ (5.08 ng mL⁻¹). The fabricated sensor showed anti‐interference ability against the biological common interferents (i.e. baicalein, baicalin) and provided to be reliable for the determination of chrysin in Chinese medicinal herb Oroxylum indicum and chrysin capsules samples with satisfactory results.     

Titanium Anodes with Active Coatings Based on Iridium Oxides: The Chemical Composition of the Coatings and the Distribution of Their Components over Depth on Anodes Made of IrO2, IrO2 + TiO2, IrO2 + RuO2 + TiO2, and IrO2 + RuO2 + TiO2 + Ta2O5

The distribution of components of active coatings over depth and the valence of metals that constitute the coatings on the IrO₂, IrO₂ + TiO₂, IrO₂ + RuO₂ + TiO₂, and IrO₂ + RuO₂ + TiO₂ + Ta₂O₅ anodes are established using Auger electron spectroscopy and x-ray photoelectron spectroscopy. It is shown that all metals, with the exception of tantalum, exist in a coating in a tetravalent state, in the form of relevant dioxides. Tantalum is present in the coatings in the form of Ta₂O₅. Etching the coatings with the argon and neon ions leads to the reduction of iridium and ruthenium dioxides to relevant metals and a partial reduction of TiO₂ to TiO. It follows that the x-ray photoelectron spectroscopy method allows one to determine the valence of metals that make up a coating only in the surface layers of the coatings. It is shown that for all the anodes, with the exception of anodes containing Ta₂O₅, the composition of a coating barely alters with depth and satisfactorily conforms to the composition specified by the coating formula. For the anodes whose coating is containing Ta₂O₅ there is observed high enrichment of surface layers of the coating by iridium and tantalum. This is probably explained by the system's multiphaseness and by a substantial difference in the temperatures at which the formation of relevant phases occurs in the course of pyrolysis.     

刷涂热分解法制备Ti/SnO2-Sb2O5阳极及其性能

通过刷涂热分解法制备了锑掺杂的钛基二氧化锡(Ti/SnO2-Sb2O5)涂层电极. 在酸性介质中, 用扫描电镜(SEM)、X射线衍射仪(XRD)、循环伏安和快速寿命测试等方法研究了Ti/SnO2-Sb2O5电极制备条件、电极结构、性能和寿命. 结果表明, Ti/SnO2-Sb2O5电极涂层具有“干泥”结构, 用锡锑摩尔比为9:1的涂液组成、在550 ℃烧结温度下制备的Ti/SnO2-Sb2O5的电极涂层平整致密,龟裂小, 电极孔隙率小, 稳定性最好.     

Ni-Nb2O5和Ni-Cu-Nb2O5催化甲烷燃烧活性研究

在微型固定床反应器中考察了新型甲烷催化燃烧催化剂Ni-Nb2O5和Ni-Cu-Nb2O5的活性．实验结果表明，含Nb2O5的Ni及Ni-Cu双金属催化剂具有好的催化甲烷低温燃烧性能，其甲烷转化率与反应温度、活性组分含量和空速有关．70％Ni担载量的Ni-Nb2O5催化剂可使甲烷在500℃时完全转化，并具有稳定的催化活性．Ni-Cu-Nb2O5体系催化剂中，Ni／Cu比为65／25时催化剂具有最佳的活性；该催化剂中Nb2O5可以在一个比较宽的范围内调节，并在此调节范围内可使甲烷在550℃温度下完全转化．