Fabrication and characterization of Mn-doped CuO thin films by the SILAR method

Thin films of un-doped and Mn-doped CuO nanostructures have been deposited on glass substrates via the SILAR method. The morphological, compositional, structural and optical properties of the films have been investigated by scanning electron microscopy, energy dispersive spectroscopy, X-ray diffraction analysis and UV–vis spectrophotometry. The analyzed results indicate that the obtained films consist of plate-like nanostructures. From the EDS analysis it is seen that Mn-doping concentration affects the shapes of the nanostructures. XRD results show that all of the films have monoclinic structure. From the room temperature UV–vis analysis it is found that the optical band gap of the films increases with increasing Mn-doping concentrations.     

可聚合的酸性功能化离子液体的合成及表征

以1-乙烯基咪唑为原料,分别与溴乙酸、3-溴丙酸、5-溴戊酸、6-溴己酸一步合成反应,得到几种可聚合酸性离子液体。离子液体的酸度采用酸度计和吡啶红外光谱探针法进行了表征。结果表明,由于咪唑环的吸电子效应,咪唑环的引入提高了对应羧酸的酸性,红外光谱表明羧基咪唑离子液体具有Bronsted酸性,且1-乙烯基-3-乙酸基咪唑溴盐的酸性最强,它们可分别与乙二醇二甲基丙烯酸酯进行沉淀聚合,得到白色的聚合物。     

Synthesis of acrolein by gas‐phase dehydration of glycerol over silica supported Bronsted acidic ionic liquid catalysts

BACKGROUND: Glycerol has become readily available as a byproduct from the biodiesel industry. High functionality and relatively low price make it a potential building block to produce value‐added derivatives such as acrolein. RESULTS: Dehydration of glycerol to acrolein was performed over several silica supported Brønsted acidic ionic liquids as catalysts. All the catalysts prepared were active for the synthesis of acrolein (conversion of glycerol was observed in the range 35–90% with selectivity to acrolein in the range 29–58%). CONCLUSIONS: Catalyst prepared from triphenyl (3‐sulfopropyl) phosphonium 4‐methylbenzenesulfonate gave good activity and selectivity at 4 h reaction time. The conversion of glycerol decreased with increase in glycerol concentration. Higher temperature (325 °C) resulted in significantly lower conversion as well as selectivity to acrolein. With the use of two additional traps cooled to ? 7 °C, the selectivity to acrolein increased significantly for good catalysts. Copyright © 2010 Society of Chemical Industry     

酸性功能化离子液体催化合成苹果酯及其同系物

制备了一种吡嗪型酸性功能化离子液体,1-(4-磺酸基)丁基-3-甲基吡嗪四氟硼酸盐([4-Sulfbmpyrazine][BF4]),并以其为酸性催化剂,合成了苹果酯及其同系物,采用正交实验方案对合成条件进行了考察,实验结果表明,以[4-Sulfbmpyrazine][BF4]为催化剂合成苹果酯的较优条件为:反应物物质...     

功能化酸性离子液体催化合成氯乙酸异丙酯的研究

研究了功能化酸性离子液体催化合成氯乙酸异丙酯的反应,考察了不同离子液体、反应温度、反应时间和离子液体与反应物物质的量比［n(离子液体)∶n（反应物）］等对反应的影响。结果表明,以离子液体N-(4-磺酸基丁基)吡啶硫酸氢盐｛［(CH2)4SO3HPy］HSO4｝为催化剂,在60 ℃、n(离子液体)∶n（反应物）=1∶5,反应4 h后,反应的转化率和选择性分别为91%和100%。催化剂循环使用5次,催化活性不变。     

酸功能化聚醚离子液体催化合成乙酸松油酯的研究

制备和表征了酸功能化聚醚离子液体1-(3-磺酸)丙基-3-聚氧乙烯醚基咪唑磷酸二氢盐-［HSO₃－(CH₂)₃－im－(CH₂CH₂O)nH］H₂PO₄,并用于催化合成乙酸松油酯的反应,考察了反应时间、反应温度、原料配比和催化剂用量等因素对反应的影响。在n(松油醇)∶n(乙酸酐)=1∶1.5,松油醇5.1 g、离子液体1.5 g、反应温度40 ℃和反应时间8 h条件下,松油醇转化率超过99.5%,乙酸松油酯的选择性为87.8%;并对离子液体的重复使用性能进行了考察,表明离子液体不经处理直接重复使用6次后,松油醇的转化率为99.4％,乙酸松油酯的选择性为88.3％,具有较好的重复使用性能。     

离子液体催化合成乙二醇双丙烯酸酯

使用酸性离子液体［Hnmp］HSO₄作为合成乙二醇双丙烯酸酯的催化剂,考察了原料配比、反应温度、反应时间、催化剂用量和带水剂用量对反应的影响,结果表明,当n(乙二醇)∶n(丙烯酸)=1.0∶2.2、反应温度为（120～125） ℃、反应时间60 min、催化剂用量为酸醇总物质的量的2.00%和带水剂甲苯用量20 mL的条件下, 酯化率达90.9%。     

磺酸型离子液体催化5-甲基-2-丙酰基呋喃的合成

合成了磺酸型离子液体催化剂[TEA-SO3H][HSO4],用以催化2-甲基呋喃和丙酸酐的付克酰基化反应合成5-甲基-2-丙酰基呋喃。结果表明,离子液体催化剂比磷酸、多聚磷酸等无机酸催化剂具有更高的产率,且催化剂可以重复利用4次以上。     

酸性离子液催化剂的制备及特性表征

采用两步法合成了4种含—SO3H基团的Brφnsted酸性离子液催化剂,对所合成的离子液体进行了红外光谱表征,运用热重分析仪测定了离子液体的热分解温度,探索采用pH计法和Hammett指数法进行离子液体的酸性测定。实验数据表明,所合成的离子液催化剂具有良好的耐热性和较高的酸强度,其结构特征与目标物吻合,产物中杂质少。     

Preparation and characterization of the lead-free piezoelectric ceramic of Bi0.5Na0.5TiO3 doped with CuO

This study investigates the effects of copper oxide (CuO) addition, calcining temperature, and sintering temperature on the microstructure and the electrical properties (such as dielectric constant and loss tangent) of lead-free piezoelectric ceramic of bismuth sodium titanate (Bi_0.5Na_0.5TiO₃), BNT, which was prepared using the mixed oxide method. Three kinds of starting powders (Bi₂O₃, Na₂CO₃ and TiO₂) were mixed and calcined. This calcined BNT powder and a certain weight percentage of CuO were mixed, calcined, and compressed into a green compact of BNT-CuO. This green compact of BNT-CuO was sintered to be a disk doped with CuO, and its characteristics were measured. In this study, the calcining temperature ranged from 700 to 1000 °C, the sintering temperature ranged from 950 to 1050 °C, and the weight percentages of CuO doping included 2, 4, 6, and 8 wt.%. The largest relative density of the BNT-CuO disk obtained in this study was 96.7% at the calcining temperature of 700 °C, the sintering temperature of 950 °C, and 4 wt.% of CuO addition. The corresponding dielectric constant and loss tangent were 494 and 0.181%, respectively. This study shows that adding CuO to the BNT not only improves the relative density and the dielectric constant of the BNT disk, but it also lowers the sintering temperature.     

功能化酸性离子液体催化合成丙酸异戊酯

研究了功能化酸性离子液体催化合成丙酸异戊酯的反应,考察了不同离子液体、反应温度、反应时间、离子液体与反应物物质的量比及催化剂重复使用次数等因素的影响。以功能化酸性离子液体［(CH₂)₄SO₃HMIm］HSO₄为催化剂,在60 ℃、n（丙酸）∶n（异戊醇）∶n（离子液体）=5∶5∶1和反应时间2 h的条件下,异戊醇转化率99.43%,丙酸异戊酯选择性100%。催化剂循环使用5次,催化活性基本不变。     

酸性离子液体催化合成三醋酸甘油酯

合成了［HSO₃-pmim］Cl、［HSO₃-pmim］［H₂PO₄］、［HSO₃-pmim］［BF₄］和［HSO₃-pmim］ ［HSO₄］离子液体，用1H-NMR和FT-IR对离子液体的结构进行了确定。将几种酸功能化离子液体应用于三醋酸甘油酯的合成反应中，筛选出了一种催化效果好又可以重复使用的离子液体［HSO₃-pmim］［HSO₄］。考察了催化剂用量、原料配比和反应时间对反应的影响，得到了较佳反应条件：n(甘油)∶n（醋酸）=1∶8，催化剂用量为醇酸总质量的5.8%，反应时间6 h，反应温度(80~90) ℃。对该功能化离子液体的重复使用性进行了考察，重复使用10次后，三醋酸甘油酯的收率仍大于90%。     

酸性离子液体中苯甲醇催化氧化合成苯甲醛

在没有任何有机溶剂和卤素的条件下，以30%H₂O₂为氧化剂，Na₂WO₄·2H₂O为催化剂，在酸性离子液体[(CH₂)₄SO₃HMIm]TSO中，研究了苯甲醇选择性氧化合成苯甲醛。在n(苯甲醇)∶n（H₂O₂）∶n(离子液体)∶n(Na₂WO₄·2H₂O)=40∶48∶1∶1、90 ℃和3 h条件下，催化效果最好，此时苯甲醇转化率为90.1%，苯甲醛选择性为92.1%。反应结束后，产物和离子液体分层，通过简单的倾倒即可分离产物。分离后的离子液体经真空干燥脱水后重复使用4次，催化活性基本不变。     

以酸性离子液体为催化剂的芦竹碱合成

以1-甲基咪唑为原料, 经1-溴丁烷N-烷基化, 再与H₂SO₄进行阴离子交换得到酸性离子液体1-丁基-3-甲基咪唑硫酸氢盐([bmim]⁺ HSO₄^-), 并以此为催化剂研究了以吲哚为原料的芦竹碱的合成, 收率可达81.6%, 催化剂连续使用4次收率基本维持不变。研究结果表明, 在芦竹碱的合成反应中离子液体催化剂相比质子酸催化, 具有环境友好, 催化活性可接受, 可重复利用的优良性能。     

High performance fiber-shaped flexible asymmetric supercapacitor based on MnO2 nanostructure composited with CuO nanowires and carbon nanotubes

The demand for wearable electronics has greatly promoted the development of flexible supercapacitors. Herein, we develop a series of approaches to fabricate a fiber-shaped supercapacitor with flexibility. In the device, CuO@MnO₂, carbon nanotube (CNT)@MnO₂ and PVA-KOH are respectively used as inner electrode, outer electrode and gel electrolyte. The approaches including in-situ growth of CNTs, in-situ etching removal of SiO₂ template and in-situ filling of gel electrolyte via hydrothermal process are explored to protect the device from structure damage caused by external forces and to maximize effective contact areas between active electrode materials and gel electrolyte. The optimized supercapacitor of copper wire@CuO@MnO₂//PVA-KOH//CNT@MnO₂ demonstrates a good capacitive performance (5.97 F cm^?3) and exhibits a high energy density (0.38 mWh cm^?3) at a power density of 25.5 mW cm^?3. In addition, it has perfect cycling stability (77% after 2000 cycles) with excellent flexibility. Therefore, this work will provide desirable processes to construct fiber-shaped supercapacitors as flexible and wearable energy storage devices.     

功能化酸性离子液体催化缩醛(酮)的合成

研究了以功能化酸性离子液体1-甲基-3-(4-磺酸基)丁基咪唑硫酸氢盐为催化剂,在无任何有机溶剂的条件下醛(酮)与二元醇的缩合反应,同时考察了催化剂用量、反应时间和反应温度等因素对缩醛(酮)收率的影响。得出最佳反应条件为:反应温度353 K,醛(酮)∶IL(摩尔比)=5∶1,此时缩醛(酮)收率最高可达到93.8%。反应体系无需脱水,产物易于分离,催化剂重复使用5次,其催化活性基本不变。     

酸性离子液体和Na2WO4·2H2O催化

以酸性离子液体和Na₂WO₄·2H₂O组成的体系为催化剂，过氧化氢为氧化剂，将催化柴油中的噻吩硫氧化为砜类物质，并通过NMP将其萃取出来，同时考察了反应温度、反应时间和催化剂用量等因素对氧化脱硫反应的影响，得出最佳反应条件为：3 mL油样（含硫200 μg·g^_-1），1 g离子液体，0.021 g 钨酸钠（Na₂WO₄·2H₂O）， 0.7 mL过氧化氢，反应温度323 K，反应时间3 h，萃取剂与柴油体积比为1∶1，此时样品中的硫可降低到23 μg·g^-1。反应结束后，可以通过简单的倾倒将油样和催化剂分离，催化剂重复使用5次，催化活性基本不变。     

酸功能化离子液体催化合成三乙酸甘油酯

合成了[HSO3-pmim]Cl、[HSO3-pmim][BF4]、[Hpyro][HSO4]和[HSO3-pmim][PTSA]离子液体,用1H-NMR和FT-IR对离子液体的结构进行了确定。将这几种酸功能化离子液体应用于三乙酸甘油酯的合成反应中,筛选出了一种催化效果好、可重复使用的离子液体[HSO3-pmim][PTSA]。考察了催化剂用量、原料配比、反应时间和反应温度对反应结果的影响。得到了较佳反应条件:即n(甘油)︰n(乙酸)=1︰8,催化剂用量为醇酸总质量的10.5%,反应时间6 h,反应温度120℃。并对离子液体的重复使用性进行了考察,重复使用7次后,三乙酸甘油酯的收率仍大于90%。     

新型环己亚胺类离子液体的合成及其催化酯化反应性能

利用环己亚胺与1,3-丙烷磺酸内酯生成的1-(3-磺丙基)环己亚胺盐,合成了2种新型Br?nsted酸性离子液体1-(3-丙磺基) 环己亚胺硫酸氢盐（[HMIPS]HSO4）和1-(3-丙磺基) 环己亚胺对甲苯磺酸盐（[HMIPS]OTs）。采用1H NMR、FT-IR、LC-ESI-MS及DSC-TG等方法对其进行了表征。结果表明,所合成的[HMIPS]HSO4和[HMIPS]OTs是一类新型的Br?nsted酸性离子液体。该类型离子液体含有环己亚胺7元环,分解温度高于260℃,其水溶液的pH值与相同浓度的硫酸水溶液的相近,具有较强的Br?nsted酸性。最后考察了所合成的新型离子液体对柠檬酸和正丁醇酯化反应的催化性能,并与传统咪唑类离子液体进行了对比。结果显示,所合成的新型离子液体具有良好的催化活性,[HMIPS]HSO4为催化剂时,在n(柠檬酸):n(正丁醇):n([HMIPS]HSO4)＝5:1:0.02,110-130℃和回流反应2 h的条件下,柠檬酸的转化率为98.3%,柠檬酸三丁酯的收率可达97.5%。而传统的咪唑离子液体[MIMPS]HSO4为催化剂时,柠檬酸的转化率和柠檬酸三丁酯的收率分别为95.8%和94.7%。[HMIPS]HSO4催化剂在重复使用10次后催化活性未见明显下降。     

Electrochemical behavior of CuO/rGO nanopellets for flexible supercapacitor,non-enzymatic glucose,and H2O2 sensing application

In the present article, graphene oxide (GO) sheets and monoclinic copper oxide (CuO) nanocrystals are connected with each other and result in the formation of CuO/rGO nanopellets, and these nanopellets synthesized using coprecipitation method. The nanopellet structured CuO/rGO composite on carbon cloth, which act as current collector exhibits specific capacitance of 188 F g^?1 at a current density of 0.2 A g^?1 and up to 96.3% capacity retention after 2000 charge-discharge cycles. It shows a maximum energy density of 7.32 Wh kg^?1 and power density of 53 W kg^?1. The glucose sensing characteristics of CuO/rGO nanopellet is investigated on carbon cloth and ITO substrate. It shows glucose sensitivity of 0.805 mA mM^?1 cm^?2 and 0.2982 mA mM^?1 cm^?2 for a bundle like structured CuO/rGO composite on carbon cloth and ITO substrate, respectively. Further H₂O₂ sensing is studied on ITO substrate, which manifests H₂O₂ sensitivity of 84.39 μA mM^?1 cm^?2. The results indicate that nanopellet structured CuO/rGO composite could be a promising electrode material for supercapacitor, glucose, and H₂O₂ sensor.