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1.
传统的聚苯胺/杂多酸(PANI/HPA)掺杂材料的化学制备方法是一步法和二步法[1].这两种方法由于使用了质子酸(如HCl)和氧化剂[如(NH4)2S2O8],不可避免地在材料中引入了与杂多阴离子竞争的抗衡阴离子(如Cl-,SO42-),使得掺杂材料的组成复杂,功能性能受到影响.本文用一种新的合成方法,即不用其他质子酸和氧化剂,利用H3PMo12O40@nH2O和H4PMo11VO40@nH2O杂多酸独特的性质--集质子酸和氧化性于一身,将HPA直接与苯胺作用,制备了仅以杂多阴离子为唯一掺杂抗衡离子的PANI/HPA掺杂材料.所合成的材料具有导电性和荧光性.  相似文献   

2.
采用浸渍法制备了一系列H3[PMo12O40]·nH2O/SiO2催化剂(Catω),其结构和性能经XRD,N2-BET和NH3-TPD表征。以甘油脱水制备烯丙醇为探针反应,考察了Catω的催化性能。结果表明:H3[PMo12O40]·nH2O负载量为1.0%(ω=1%)的催化剂(Cat1)具有最佳的催化性能,甘油转化率,烯丙醇选择性和时空收率分别为100%,35.9%,3.2 mmol·g-1·h-1;催化剂的催化性能与H3[PMo12O40]·nH2O负载量有很好的相关性。  相似文献   

3.
推荐一个设计性综合化学实验——己二酸的绿色合成   总被引:1,自引:0,他引:1  
设计了一个综合实验——己二酸的绿色合成。分别用H3PW12O40·nH2O、H6P2W18O62·nH2O、H3PW6Mo6O40·nH2O催化H2O2氧化环己酮半微量合成己二酸,用红外光谱分析了催化剂和产物的结构。  相似文献   

4.
在氧化铝模板中制备了HPA/PANI纳米线列阵,SEM、TEM表明列阵中纳米线直径约为80 nm;XRD与FT-IR证明形成了有效掺杂;单根纳米线的导电率为16.2 S.cm-1;材料的TG-DTA表明PANI纳米线材料有三步失重过程,失去吸附水过程,多酸失去结晶水和PANI结构持续分解过程,多酸结构分解过程;在氧化聚合过程中H4PMo11VO40即为质子酸又为氧化剂和掺杂剂;聚合反应采用自由基机理进行,掺杂反应发生在形成醌二亚胺式自由基正离子和双苯胺式自由基正离子和醌二亚胺式自由基正离子偶联聚合成链结构时.  相似文献   

5.
以H3PMo12O4·0nH2O、H4PMo11VO4·0nH2O和(NH4)6P2Mo18O6·2nH2O3种杂多化合物为钼源,采用直接混合后陈化的方法合成了多形貌A113基钼酸盐晶体,相应A113基钼酸盐晶体的形貌和尺寸分别是斜方三棱柱形(80μm×30μm)、星形(30μm×10μm)和叶片形(500μm×150μm)。粉末X射线衍射结果表明这3种多形貌A113基钼酸盐晶体结晶较好,在2θ为6.65°、8.00°和14.16°处都有强而尖锐的衍射峰。而以Na2MoO4·2H2O为钼源时只能制得无定形簇合物。根据ICP、FTIR和TG/DTG结果给出多形貌的Al13基钼酸盐晶体的化学简式为Na[AlO4Al12(OH)24(H2O)12][MoO4]·48H2O。初步探讨了A113基钼酸盐晶体的形成机理。  相似文献   

6.
利用常规水溶液法制备了三种基于饱和Keggin结构阴离子的有机-无机复合杂多化合物[Pr(pydc)(H2O)6]2H[PMo12O40]·4H2O(1)、[Nd(pydc)(H2O)6]2H[PMo12O40]·4H2O(2)和[Tb(pydc)(H2O)6]2H[PMo12O40]·4H2O(3)(pydc=2,6...  相似文献   

7.
孙晶晶  魏梅林 《化学研究》2014,(1):63-66,71
制备了异烟酸氮氧化物(简计为HINO)/磷钼酸镍有机-无机络合物({[Ni(H2O)8][H(H2O)2.5](HINO)4(PMo12O40)}n;简计为1)掺杂硅胶复合物(简计为1-SG1);采用红外光谱仪和X射线衍射仪证实了合成产物的结构.结果表明,化合物1的结构特征在1-SG1硅胶复合物中得以保留.与此同时,在约98%的相对湿度下,1-SG1在温度55~100℃范围内显示良好的导电性,其质子导电率达到8.98×10-3~1.03×10-2 S·cm-1;并且,在同等条件下,1-SG1的质子导电性优于化合物1.  相似文献   

8.
设计了一个综合实验--乙基叔丁基醚的绿色合成。分别用自制的H3P12W40·nH2O、H4Si12W40·nH2O和H3PW6Mo6O40·nH2O催化合成乙基叔丁基醚,用红外光谱分析了催化剂和产物的结构,用气相色谱仪和核磁共振波谱仪对产物的纯度和结构进行分析。  相似文献   

9.
在孔板式吸收器(孔板孔径:50μm-70μm)中对杂酸水溶液脱除烟气中SO2的新方法进行了研究。在所考察的几种杂多酸中,H3PW12O40和H2SiW12O40对SO2的脱除率较为接近,H7PMo2W12O49和Na2HPMo12O40对SO2的脱除率相对较高,其中后者对SO2的脱除率最高。杂多酸(HPA)对SO2的脱除率随HPA浓度的提高而增高,随进气中SO2的浓度或吸收温度提高而减低。常温有利于HPA对SO2的脱除。NaCl,NH4VO3,CuSO4及H3PO4这四种添加剂均能提高HPA对SO2的脱除率。复配体系中,以上添加剂对HPA的最优配比为:NaCl/HPA:H3PO4/HPA:NH4VO3/HPA:CuSO4/HPA=1/6:1/8:1/2:1/4。进气中有NOx存在下HPA对SO2的脱除反应式,这些反应式能够很好地说明NOx的作用效果。以上结果表明:HPA水溶液具有很好的烟气脱硫应用前景。  相似文献   

10.
陈林  魏梅林 《化学研究》2014,(5):461-465
以磷钼酸和2-(2-羟基苯)苯并咪唑(L)为原料制备了具有质子导电性的有机-无机化合物[H3L2(PMo12O40)·7H2O·4CH3OH]n(1).单晶X射线衍射分析结果表明化合物1具有基于磷钼酸、2-(2-羟基苯)苯并咪唑及溶剂甲醇分子的二维氢键网络结构;质子导电性能测试结果表明该化合物在100℃、相对湿度为98%时的电导率达到10-4 S·cm-1.  相似文献   

11.
Chemical delithiation of layered LiCoO2, LiNi0.5Mn0.5O2, and Li2MnO3 and spinel LiMn2O4 cathodes have been investigated with both an acetonitrile (non-aqueous) solution of the oxidizer NO2BF4 and an aqueous acid. The products have been characterized by X-ray diffraction, wet chemical analyses for lithium and oxygen contents, infrared spectroscopy, and thermogravimetric analysis to determine whether or not protons are incorporated into the lattice during the delithiation process. While the delithiation in aqueous acid medium leads to an incorporation of protons into the layered oxide lattice, the non-aqueous delithiation with NO2BF4 does not involve any proton insertion into the lattice. In contrast to the layered oxides, the chemical delithiation of spinel LiMn2O4 even in the aqueous acid medium does not involve any proton insertion into the lattice.  相似文献   

12.
Self‐assembled crystalline porous organic salts (CPOSs) formed by an acid–base combination and with one‐dimensional polar channels containing water molecules have been synthesized. The water content in the channels of the porous salts plays an important role in the proton conduction performance of the materials. The porous salts described in this study feature high proton conductivity at ambient conditions and can reach as high as 2.2×10−2 S cm−1 at 333 K and under high humid conditions. This is among the best conductivity values reported to date for porous materials, for example, metal–organic frameworks and hydrogen‐bonded organic frameworks. These materials exhibiting permanent porosity represent a group of porous materials and may find interesting applications in proton‐exchange membrane fuel cells.  相似文献   

13.
采用模板法, 用正硅酸乙酯和3-巯丙基-三甲氧基硅烷的混合溶胶, 在聚苯乙烯胶晶间隙中原位转化, 除去模板后用双氧水将巯基氧化成磺酸基, 首次成功地制备了大孔规整排列的3DOM SiO2-SO3H材料. 样品用SEM, EDS, FT-IR等方法进行了测试表征. 结果表明, 所得到材料的三维大孔结构规整性十分好, 大孔孔径大约250 nm, 并由大约80 nm的小孔相连; 磺酸基很好地嵌入孔壁基质中, 吡啶吸附测定显示了典型的质子酸特征, 而且酸中心随硫含量增加而增多. 对乙酸与正丁醇的酯化反应显示了良好的催化性能, 磺酸含量越大, 催化活性越高. 这一研究为开发新型高效的固体酸催化剂提供了很有意义的结果.  相似文献   

14.
Novel proton conducting organic electrolyte containing fluoroalkylated 1,2,3-triazole was synthesized via intramolecular cyclisation of vinyl azides. FT-IR, elemental analysis and NMR methods were used for the characterization of the resulting organic molecule. Triazole containing sample was doped with triflic acid to obtain proton conducting organic electrolytes. Thermal stability of these materials was analyzed with thermogravimetric analysis (TGA) and the melting temperatures were measured by differential scanning calorimetry (DSC). The effect of acid content on the proton conductivity was investigated with impedance spectrometer and the maximum proton conductivity was measured as 10−2 S/cm at 150 °C.  相似文献   

15.
The development of solid‐state proton‐conducting materials with high conductivity that operate under both anhydrous and humidified conditions is currently of great interest in fuel‐cell technology. A 3D metal–organic framework (MOF) with acid–base pairs in its coordination space that efficiently conducts protons under both anhydrous and humid conditions has now been developed. The anhydrous proton conductivity for this MOF is among the highest values that have been reported for MOF materials, whereas its water‐assisted proton conductivity is comparable to that of the organic polymer Nafion, which is currently used for practical applications. Unlike other MOFs, which conduct protons either under anhydrous or humid conditions, this compound should represent a considerable advance in the development of efficient solid‐state proton‐conducting materials that work under both anhydrous and humid conditions.  相似文献   

16.
In this paper, we demonstrate that nanoscale membrane electrode assemblies, functioning in a H2/O2 fuel cell, can be fabricated by impregnation of anodic alumina porous membranes with Nafion® and phosphotungstic acid. Porous anodic alumina is potentially a promising material for thin-film micro power sources because of its ability to be manipulated in micro-machining operations. Alumina membranes (Whatman, 50 μm thick, and pore diameters of 200 nm) impregnated with the proton conductor were characterized by means of scanning electron microscopy, X-ray diffraction, and thermal analysis. The electrochemical characterization of the membrane electrode assemblies was carried out by recording the polarization curves of a hydrogen–oxygen 5 cm2 fuel cell working at low temperatures (25?÷?80 °C) in humid atmosphere. Our assemblies realized with alumina membranes filled with phosphotungstic acid and Nafion® reach respectively the peak powers of 20 and 4 mW/cm2 at room temperature using hydrogen and oxygen as fuel and oxidizer.  相似文献   

17.
纳米α-Fe~2O~3的XANES研究   总被引:2,自引:0,他引:2  
石瑶  邹雁  陈晓枫  邓红梅 《化学学报》2001,59(1):103-108
选择纳米α-Fe~2O~3体系,运用X射线近边吸收谱(XANES)技术对纳米材料进行分析。结果表明,三种尺寸的纳米α-Fe~2O~3样品(颗粒尺寸分别是3nm,10nm和55nm)与粗颗粒商品的氧K边XANES谱的不同之处在于,纳米样品出现了一个新的吸收B峰。研究揭示,该峰可能是纳米α-Fe~2O~3中晶界部分氧的2p-4sp杂化所产生的一个新电子跃迁末态造成的。进一步的研究表明,随着纳米α-Fe~2O~3的粒子尺寸减小,氧的2p轨道和铁的3d轨道杂化增加,主要体现在2p-e~g杂化程度加剧,使得纳米颗粒中铁周围的氧配位八面体畸变程度加强。最后,通过对3nm样品在研磨和不研磨两种制样方式获得的氧K边XANES谱分析,证实纳米粒子体系中存在特殊的协同作用力。  相似文献   

18.
The development of environmentally friendly solid acid catalysts is a priority task. Highly oxidized activated carbon and their ion-substituted (saline) forms are effective proton transfer catalysts in esterification, hydrolysis, and dehydration, and thus are promising candidates as solid acid cata-lysts. Computations by the ab initio method indicated the cause for the enchanced acidity of the carboxylic groups attached to the surface of highly oxidized carbon. The synthesis of phosphorilated carbon was considered, and the proton transfer reactions catalyzed by them in recent studies were analyzed. The development of an amorphous carbon acid catalyst comprising polycyclic carbonaceous (graphene) sheets with –SO3H, –COOH and phenolic type OH-groups was carried out. These new catalysts were synthesized by partial pyrolysis and subsequent sulfonation of carbohydrates, polymers, and other organic compounds. Their high catalytic activities in proton transfere reactions including the processing of bio-based raw materials was demonsrated.  相似文献   

19.
A new simple synthesis route for 2,2,2‐trinitroethyl chloroformate ( 1 ), from easily available starting materials 2,2,2‐trinitroethanol and phosgene is presented. 2,2,2‐Trinitroethyl carbamate ( 2 ) was obtained by the reaction of 1 with aqueous ammonia. The nitration of 2 with anhydrous nitric acid and sulfuric acid yields 2,2,2‐trinitroethyl nitrocarbamate ( 3 ), which has potential as a perchlorate free high energetic dense oxidizer with a high oxygen balance of Ω(CO2) = +14.9 %. The thermal stability was studied using differential scanning calorimetry and the energies of formation were calculated on the CBS‐4M level of theory, as well as several detonation parameters and propulsion properties were determined. In addition to full spectroscopic characterization, X‐ray diffraction studies were performed for 2 and 3 .  相似文献   

20.
提高质子交换膜燃料电池(PEMFCs)的工作温度,不但可以提高电催化剂的活性以及电催化剂对原料气中CO等杂质气体的耐受能力,少用甚至不用Pt 等贵金属作电催化剂,还可以简化PEMFCs的水热管理系统,提高PEMFCs的综合能量转化效率. 实现高温PEMFCs的核心是开发能够适用于高温PEMFCs的高温质子交换膜(HT-PEM),是PEMFCs的研究热点. 在众多HT-PEM候选材料中,基于膦酸基的质子交换膜材料是最具前途的候选材料之一,是制备HT-PEM的主要研究方向. 本文综述了基于膦酸基的HT-PEM的研究进展,讨论了膦酸基参与的质子传导机理,比较了纯聚合物膦酸膜、膦酸基接枝改性膜、酸-碱两性膜、掺杂型复合膜的电导率、物理化学稳定性、机械性能等. 最后,展望了基于膦酸基的HT-PEM的发展趋势.  相似文献   

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