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1.
将Co3O4/ZnO针状纳米棒材料修饰到针灸针表面用于检测葡萄糖浓度的变化。首先采用水热法在针灸针表面得到 Co(CO30.5(OH)·0.11H2O针状纳米棒前驱体,然后在500 ℃条件下退火3 h得到Co3O4针状纳米棒阵列。再采用浸渍法将预制备好的ZnO量子点修饰到Co3O4针状纳米棒表面,得到Co3O4/ZnO复合修饰的针灸针。研究发现此针灸针对葡萄糖具有较好的电流响应(2 264.27 μA·L·mmol-1·cm-2)、较快的响应速度(<4 s)及较低的检测极限(0.311 μmol·L-1S/N=3))。且该针灸针在用于检测人体模拟细胞液中葡萄糖浓度时,对抗坏血酸和尿素等表现出较强的抗干扰性。  相似文献   

2.
将Co3O4/ZnO针状纳米棒材料修饰到针灸针表面用于检测葡萄糖浓度的变化。首先采用水热法在针灸针表面得到Co(CO30.5(OH)·0.11H2O针状纳米棒前驱体,然后在500 ℃条件下退火3 h得到Co3O4针状纳米棒阵列。再采用浸渍法将预制备好的ZnO量子点修饰到Co3O4针状纳米棒表面,得到Co3O4/ZnO复合修饰的针灸针。研究发现此针灸针对葡萄糖具有较好的电流响应(2 264.27 μA·L·mmol-1·cm-2)、较快的响应速度(<4 s)及较低的检测极限(0.311 μmol·L-1S/N=3))。且该针灸针在用于检测人体模拟细胞液中葡萄糖浓度时,对抗坏血酸和尿素等表现出较强的抗干扰性。  相似文献   

3.
采用碳酸盐共沉淀法通过调节NH3·H2O用量来实现可控制备超高倍率纳米结构LiNi1/3Co1/3Mn1/3O2正极材料。NH3·H2O用量会对颗粒的形貌、粒径、晶体结构以及材料电化学性能产生较大的影响。X射线衍射(XRD)分析和扫描电镜(SEM)结果表明,随着NH3·H2O用量的降低,一次颗粒形貌由纳米片状逐渐过渡到纳米球状,且nNH3·H2O:(nNi+nCo+nMn)=1:2样品晶体层状结构最完善、Li+/Ni2+阳离子混排程度最低。电化学性能测试结果也证实了nNH3·H2O:(nNi+nCo+nMn)=1:2样品具有最优异的循环稳定性和超高倍率性能。具体而言,在2.7~4.3 V,1C下循环300次后的放电比容量为119 mAh·g-1,容量保持率为81%,中值电压基本无衰减(保持率为97%)。在100C(18 Ah·g-1)的超高倍率下,放电比容量还能达到56 mAh·g-1,具有应用于高功率型锂离子电池的前景。此NH3·H2O比例值对于共沉淀法制备其他高倍率、高容量的正/负极氧化物材料具有一定的工艺参考价值。  相似文献   

4.
分别以四水磷酸铁(FePO4·4H2O)和二水草酸亚铁(FeC2O4·2H2O)为铁源,采用简单便捷的流变相法制备了碳包覆LiFe0.5Co0.5PO4固溶体材料(LiFe0.5Co0.5PO4/C,简称为LFCP/C)。采用X射线衍射(XRD)、扫描电镜(SEM)、透射电镜(TEM)、恒流充放电等测试手段对复合材料的物相、形貌结构和电化学性能进行了表征和测试。结果表明,2种铁源得到的材料均为橄榄石晶型结构且结晶度良好,二者在颗粒尺寸分布、碳包覆效果和电化学性能方面具有显著的差别。用作锂离子电池正极材料时,以FeC2O4·2H2O为原料得到的LFCP/C具有更优异的电性能:在2.5~5.0 V电压范围内,0.1C倍率下(1C=150 mA·g-1),放电比容量为137.5 mAh·g-1,在10C仍具有57.6 mAh·g-1的放电比容量;0.5C循环100次后容量仍保持78.1%。该样品更佳的电化学性能主要得益于其更小的平均颗粒尺寸,更高的比表面积和理想的碳包覆效果。  相似文献   

5.
夏强  廖小刚  沈海丽  郑林  李纲  田甜 《无机化学学报》2022,38(11):2191-2201
分别采用尿素水热-煅烧法、化学浴沉积-煅烧法和草酸盐热解法制备出具有不同形貌的Co3O4(Co3O4-A、Co3O4-B和Co3O4-C) 粉体材料,对比了它们作为催化剂活化过一硫酸盐(PMS)降解亚甲基蓝(MB)的性能。结果表明,3种Co3O4材料均具有分级微/纳米结构,形貌分别呈绒球状、无规则颗粒状和纤维状。PMS在3种催化剂作用下的分解过程均符合一级反应动力学模型,反应速率常数依次为0.047 1、0.217 4和0.003 7 min-1。无规则颗粒状Co3O4-B表现出最高的PMS活化性能,是其具有最大比表面积、最高表面氧空位浓度以及表面羟基密度综合作用的结果。在催化剂用量0.02 g·L-1、PMS投加量0.6 mmol·L-1的工艺参数条件下,Co3O4-B/PMS高级氧化体系在25 min内对MB的降解即可达98.33%。电子顺磁共振测试证实Co3O4-B/PMS高级氧化体系中存在·SO4-、·OH、·O2-1O2四种活性氧物种,基于此提出了Co3O4-B活化PMS及降解MB的反应机理。  相似文献   

6.
以Co (NO32和Eu (NO33为原料,采用草酸盐-热分解法制得了系列不同Co/Eu比例(nCo/nEu)的多孔双金属复合氧化物催化剂,并对其活化过一硫酸盐(PMS)降解亚甲基蓝(MB)的性能进行对比评价。结果表明,按nCo/nEu=9制得的材料(Co9Eu1)具有最为优异的活化PMS降解MB的性能。在温度为25℃、催化剂用量和PMS浓度分别为0.10 g·L-1和0.6 mmol·L-1的反应条件下,Co9Eu1/PMS体系对MB的降解率可达86.66%,而纯Co3O4催化下的MB降解率仅为52.62%。Co9Eu1出色的催化性能是由于Eu3+的缺电子特性增强了对吸附于催化剂表面PMS的极化而使其更易被主催化成分Co3O4活化。体系中阴离子C2O42-和HCO3-的存在对Co9Eu1/PMS氧化降解MB的性能具有明显抑制作用。猝灭实验和电子顺磁共振谱(EPR)证实Co9Eu1/PMS体系中同时存在SO4-·、·OH和·O2-三种自由基型活性物种以及1O2非自由基型活性物种,其中SO4-·对MB的氧化降解起关键作用。Co9Eu1具有良好的稳定性,在连续4次循环使用中其催化性能未见明显变化。  相似文献   

7.
采用3种不同pH值的去离子水,NH4NO3和H2C2O4溶液对富锂层状正极材料Li[Li0.2Mn0.54Ni0.13Co0.13]O2进行表面化学侵蚀改性,旨在改善其整体电化学性能。ICP结果表明pH值对材料中Li的析出具有显著影响。X射线衍射(XRD)表明表面化学侵蚀对材料的结构有影响。拉曼光谱(Raman spectroscopy)表明材料表面结构发生了变化。H2C2O4溶液侵蚀过的样品的首次效率有了极大提高,但同时中值电压和循环性能显著恶化。NH4NO3溶液侵蚀过的样品的首次效率从63%提高到了85%,1C倍率下的放电比容量从149 mAh·g-1提高到194 mAh·g-1,同时保持了温和的中值电压变化曲线。通过高分辨透射电镜(HRTEM),X射线光电子能谱(XPS)和电化学阻抗谱(EIS)对改性机理进行了研究。  相似文献   

8.
采用3种不同pH值的去离子水,NH4NO3和H2C2O4溶液对富锂层状正极材料Li[Li0.2Mn0.54Ni0.13Co0.13]O2进行表面化学侵蚀改性,旨在改善其整体电化学性能。ICP结果表明pH值对材料中Li的析出具有显著影响。X射线衍射(XRD)表明表面化学侵蚀对材料的结构有影响。拉曼光谱(Raman spectroscopy)表明材料表面结构发生了变化。H2C2O4溶液侵蚀过的样品的首次效率有了极大提高,但同时中值电压和循环性能显著恶化。NH4NO3溶液侵蚀过的样品的首次效率从63%提高到了85%,1C倍率下的放电比容量从149 mAh·g-1提高到194 mAh·g-1,同时保持了温和的中值电压变化曲线。通过高分辨透射电镜(HRTEM),X射线光电子能谱(XPS)和电化学阻抗谱(EIS)对改性机理进行了研究。  相似文献   

9.
以2-(4''-羧基苯基)咪唑-4,5-二羧酸(H4CPhIDC,C12H8N2O6)为配体,用溶剂热合成了3种配位聚合物{[Cd2(CPhIDC)(bimb)]·H2O}n1)、{[Cd2(CPhIDC)(phen)2]·3H2O}n2)、{[Zn2(CPhIDC)(bpp)]·1.5H2O}n3)(bimp=1,4-双咪唑基-丁烷,phen=1,10-菲咯啉,bpp=1,3-双(4-吡啶基)-丙烷)。用元素分析、红外光谱、粉末X射线衍射和单晶X射线衍射对配合物进行了表征和结构分析。结构分析表明,主配体以完全去质子化CPhIDC4-的形式与中心金属离子形成以μ4μ5为配位模式的二维及三维聚合物。配合物13是三维网络结构,同时呈现(3,4,5)-连接的(5·6·7)(4·52·6·72)(4·52·6·74·82)拓扑结构,两者的不同之处是中心离子和辅助配体。配合物2是二维波纹状渔网结构,呈现44·62拓扑结构,在其空间填充上又类似于DNA双螺旋链的单螺旋结构。测定了产物的固体荧光光谱;用EtBr荧光探针法研究了配体及配合物与ct-DNA的相互作用。  相似文献   

10.
在溶剂热条件下合成了3个新型三维微孔同构异核金属有机骨架Ln (Na)-MOFs:{[LnNa (BDT)(H2O)3]·2H2O}n(Ln=Tb (1)、Dy (2)、Ho (3),H4BDT=3,5-二(3'',5''-二羧基苯基)-1H-1,2,4-三唑),并通过单晶X射线衍射、元素分析、热重分析和粉末X射线衍射技术对其进行表征。结构分析表明,Ln (Na)-MOFs是具有相同的异核双金属单元的三维骨架结构。荧光研究表明,Tb (Na)-MOF (1)可以荧光传感检测水中Fe3+、Cr2O72-以及乙醛分子,具有较高的灵敏度和选择性,也可用于水中邻苯二酚的电化学检测。  相似文献   

11.
The phase relations in the cross-section of the K2W2O7-K2WO4-KPO3 containing 15 mol% Bi2O3 were undertaken using flux method. Crystallization fields of K6.5Bi2.5W4P6O34, K2Bi(PO4)(WO4), Bi2WO6, KBi(WO4)2 and their cocrystallization areas were identified. Novel phase K6.5Bi2.5W4P6O34 was characterized by single-crystal X-ray diffraction: sp. gr. P−1, a=9.4170(5), b=9.7166(4), c=17.6050(7) Å, α=90.052(5)°, β=103.880(5)° and γ=90.125(5)°. It has a layered structure, which contains {K7Bi5W8P12O68} layers stacked parallel to ab plane and sheets composed by potassium atoms separating these layers. Sandwich-like {K7Bi5W8P12O68} layers are assembled from [W2P2O13] and [BiPO4] building units, and are penetrated by tunnels with K/Bi atoms inside. FTIR-spectra of K2Bi(PO4)(WO4) and K6.5Bi2.5W4P6O34 were discussed on the basis of factor group theory.  相似文献   

12.
K3InF6 is synthesized by a sol-gel route starting from indium and potassium acetates dissolved in isopropanol in the stoichiometry 1:3, with trifluoroacetic acid as fluorinating agent. The crystal structures of the organic precursors were solved by X-ray diffraction methods on single crystals. Three organic compounds were isolated and identified: K2InC10O10H6F9, K3InC12O14H4F18 and K3InC12O12F18. The first one, deficient in potassium in comparison with the initial stoichiometry, is unstable. In its crystal structure, acetate as well as trifluoroacetate anions are coordinated to the indium atom. The two other precursors are obtained, respectively, by quick and slow evaporation of the solution. They correspond to the final organic compounds, which give K3InF6 by decomposition at high temperature. The crystal structure of K3InC12O14H4F18 is characterized by complex anions [In(CF3COO)4(OHx)2](5−2x)− and isolated [CF3COOH2−x](x−1)− molecules with x=2 or 1, surrounded by K+ cations. The crystal structure of K3InC12O12F18 is only constituted by complex anions [In(CF3COO)6]3− and K+ cations. For all these compounds, potassium cations ensure only the electroneutrality of the structure. IR spectra of K2InC10O10H6F9 and K3InC12O12F18 were also performed at room temperature on pulverized crystals.  相似文献   

13.
phase diagrams of KCl-KBO2-K2CO3, K2MoO4-KBO2-K2CO3, and K2WO4-KBO2-K2CO3 ternary systems were studied by a calculation-experimental method and differential thermal analysis (DTA). The coordinates of ternary eutectics were determined to be E 1: 622°C, 8.5 mol % KBO2, 56.5 mol % KCl, and 35 mol % K2CO3; E 2: 710°C, 23 mol % KBO2, 43 mol % K2CO3, and 34 mol % K2MoO4; E 3: 710°C, 23 mol % KBO2, 43 mol % K2CO3, and 34 mol % K2WO4. The specific heats of melting of the eutectics were determined.  相似文献   

14.
Solubility in the Na2Cr2O7-(NH4)2Cr2O7-K2Cr2O7-H2O four-component water-salt system at 25, 50, and 75°C was studied for the first time. Phase field boundaries for individual salts and potassium and ammonium dichromate solid solutions, monovariant lines, and invariant points were determined. Experimental data were used to optimize the looped isohydric process of potassium dichromate preparation involving additional salts.  相似文献   

15.
马修臻  胡斌 《化学通报》2018,81(10):939-943,938
本文用高精度数字式振荡管密度计测定了288K至318K温度范围内Li2SO4 + Na2SO4 + H2O和 Li2SO4 + K2SO4 + H2O三元体系的密度。混合溶液的离子强度范围从0.1到4.5 mol.kg–1,混合溶液中Na2SO4和K2SO4的离子强度分数为0.2,0.4,0.6和0.8。用密度实验值拟合得到了不同温度下Pitzer离子相互作用模型混合参数θV和 ψV,模型的计算值与实验值的偏差在±0.002 g.cm3以内。用Pitzer模型计算了不同离子强度下三元体系的混合体积。  相似文献   

16.
The phase diagrams of the NaBO2-NaCl-Na2CO3, NaBO2-Na2CO3-Na2MoO4, NaBO2- Na2CO3-Na2WO4, and NaBO2-NaCl-Na2WO4 ternary systems were studied by a calculation-experimental method and differential thermal analysis. The coordinates of ternary eutectics were determined: E 1: 612°C, 16 mol % NaBO2, 42 mol % NaCl, and 42 mol % Na2CO3; E 2: 568°C, 12 mol % NaBO2, 28 mol % Na2CO3, and 60 mol % Na2MoO4; E 3: 575°C, 12 mol % NaBO2, 32 mol % Na2CO3, and 56 mol % Na2WO4; E 4: 628°C, 8 mol % NaBO2, 20 mol % NaCl, and 72 mol % Na2WO4; and E 5: 655°C, 9 mol % NaBO2, 53 mol % NaCl, and 38 mol % Na2WO4.  相似文献   

17.
Two compounds of formula La7A3W4O30 (with A=Nb and Ta) were prepared by solid-state reaction at 1450 and 1490 °C. They crystallize in the rhombohedric space group R-3 (No. 148), with the hexagonal parameters: , and , . The structure of the materials was analyzed from X-ray, neutron and electronic diffraction. These oxides are isostructural of the reduced molybdenum compound La7Mo7O30, which are formed of perovskite rod along [111]. An order between (Nb, Ta) and W is observed.  相似文献   

18.
Two compounds NaSr0.5Al2B2O7 and NaCa0.5Al2B2O7, have been found to crystallize into a new structure type by Rietveld refinement from X-ray powder diffraction data. Their structure belongs to hexagonal space group P63/m, with lattice parameters of , for NaSr0.5Al2B2O7 and , for NaCa0.5Al2B2O7, respectively. The structure is built up by [Al2B2O7]2− double layer and Na+/Ca2+ or Na+/Sr2+ ions alternatively stacking along the c-axis. The sites in the inter-double layer are fully occupied jointly by Na and Ca or Sr, but the intra-double layer sites are only half occupied solely by Na. A mechanism of the transition of the structure from CaAl2B2O7 to present structure type by replacing only 1% Ca by Na (2%) as observed by Chang and Keszler (Mater. Res. Bull. 33 (1998) 299) is also proposed.  相似文献   

19.
SnSbBiS4-SnS and SnSbBiS4-Sn2Sb6S11 sections were studied by physicochemical methods (DTA, X-ray powder diffraction, microstructure observation, and microhardness measurements). These sections were found to be eutectic quasi-binary sections of the SnS-Sb2S3-Bi2S3 ternary system. Solid solution regions based on the initial components were found on either side of the sections. Alloys in the solid solution region are p-type semiconductors.  相似文献   

20.
一些具有NASICON型网格结构的固体电解质具有高的电导率和好的稳定性,NASICON的意思是Na Super Ionic Conductor[1]。当NaZr2(PO4)3中P5 被Si4 部分取代时便可以得到具有NASICON结构的Na1 xZr2SixP3-xO12体系,其具有高的钠离子电导率。然而有相同结构的Li1 xZr2SixP3-xO12体系的离子电导率却很低,这是因为Li 半径太小,而NASICON三维网格结构的离子通道太大,两者不匹配而使电导率下降[2]。但当LiZr2(PO4)3中Zr4 被离子半径小些的Ti4 取代,所得LiTi2(PO4)3的通道就与Li 半径相匹配,适合于锂离子的迁移,从而使其电导率…  相似文献   

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