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1.
用电化学方法将磷钼杂多酸催化剂固定在导电聚吡咯膜电极上,从而制得具有表面功能的磷钼杂多酸掺杂的聚吡咯膜修饰碳纤维微电极。该电极既保持了磷钼杂多酸的电化学活性和电催化性能,又具有良好的稳定性,在酸性水溶液中不仅能催化还原ClO3而且对NO6-2离子有有更显著的电催化还原作用。  相似文献   

2.
采用电化学聚合法研制了磷钼杂多酸-碱性染料离子缔合物掺杂聚吡咯薄膜修饰石墨电极,研究了修饰电极的电化学行为。  相似文献   

3.
采用电化学方法在导电基体玻碳电极上制备出磷钼钒杂多酸-聚吡咯膜修饰电极,研究了NO-2在该电极上的电化学行为。结果表明,磷钼钒杂多酸-聚吡咯膜修饰电极对酸性水溶液中的NO-2具有良好的电催化还原作用,与空白玻碳电极相比。降低过电位1000mV以上,而且N0-2的浓度在5.0×10-6~1.0×10-2mol·L-1范围内,催化峰电流与NO-2浓度呈良好的线性关系,检出限可达1.0×10-6mol·L-1,用于环境水中NO-2的测定,结果良好。  相似文献   

4.
采用电化学方法以导电基体玻碳电极上制备出磷钼钒杂多酸-聚吡咯膜修饰电极,研究了NO2^-在该电极上的电化学行为。结果表明,磷钼钒杂多酸-聚吡咯膜修饰电极对酸性水溶液中的NO2^-具有良好的电催化还原作用,与空白玻碳电极相比,降低过电位1000mV以上,而且NO2^-的浓度在5.0×106-6 ̄1.0×10^-2mol·L^-1范围内,催化峰电流与NO2^-浓度呈良好的线性关系,检出限可达1.0×1  相似文献   

5.
将磷钼杂多酸聚吡咯(PMo12-PPY)用电聚合法沉积在载有多孔阳极氧化铝(AAO)的玻碳电极表面(AGCE),制备了PMo12-PPY/AGCE纳米复合材料修饰电极,并通过循环伏安(CVs)、电化学阻抗谱(EIS)方法表征了PMo-PPY/AGCE和PMo-PPY/GCE的电化学性质及电极界面反应特征.结果表明,AAO膜使电极表面粗糙度降低,电子传输的能力增强,并使氧化还原反应速度加快.  相似文献   

6.
合成了第四周期过渡金属磷钼三元杂多酸类化合物,采用电化学聚合法研制了该类杂多酸-聚吡咯薄膜修饰电极,该电极制备过程简便,快速,研究了膜电极的电化学行为,发明掺杂膜电极性能稳定,对酸性水溶液中的H2O2,NO2,ClO3,BrO^-3,IO3等物质具有较好的电催化还原作用,初步探讨了电催化还原机理。  相似文献   

7.
本文报道了1:12-磷铜杂多酸(PMo_(12)薄膜修饰碳纤维(CF)微电极的制备及其电化学性质。采用简单,快速的浸渍吸附制备的PMo_(12)薄膜修饰CF电极在酸性介质中具有很高的稳定性和氧化还原活性,电解质溶液的pH值和扫描电位范围对PMo_(12)膜的稳定性和电化学性质产生较大的影响。另一方面,PMo_(12)薄膜修饰CF微电极对酸性水溶液中的PMo_(12)和氯酸根离子(ClO)_3~-)的电催化还原作用也进行了描述。  相似文献   

8.
通过静电层层自组装方法在预修饰聚二烯丙基二甲基氯化铵的电极基片上制备了Dawson型磷钼钒杂多酸/聚酰胺-胺多层复合膜. 用X射线光电子能谱、紫外-可见光谱、循环伏安法和原子力显微镜分析表征了多层复合膜的形成过程; 用循环伏安法表征了该复合膜修饰电极的电化学性能, 研究结果表明, 该复合膜修饰的电极稳定性好, 对亚硝酸盐、溴酸盐的还原以及抗坏血酸的氧化具有良好的催化活性.  相似文献   

9.
磷钨钴和磷钨镍杂多酸化学修饰电极的研究   总被引:3,自引:0,他引:3  
杂多酸由于组成和结构上的特点,在电化学和电分析化学领域有着广泛应用[1,2]。迄今为止,有关磷钨钴和磷钨镍三元杂多酸化学修饰电极还未见报道。本文按文献方法[3]合成了磷钨钴(H3PW11CoO40·xH2O)和磷钨镍(H3PW11NiO40·xH2O)杂多酸,分别以H3PW12O40·xH2O、H3PW11CoO40·xH2O和H3PW11NiO40·xH2O杂多酸(以下简写为H3PW11MO40·xH2O,其中M代表W,Co和Ni)为修饰剂,采用电化学方法在导电基体玻碳(GC)电极上制备了H3PW11MO40/GC膜修饰电极,制备过程简便、快速。对膜电极的…  相似文献   

10.
董绍俊  金哲 《化学学报》1989,47(9):922-925
用循环伏安法研究了1:12磷钼杂多阴离子(PMo12)薄膜修饰电极的制备及其电化学行为, 发现PMo12膜强烈地吸附在玻璃碳电极表面, 溶液氢离子在PMo12膜改性电极的电化学过程中起着重要的作用, 而其它阴离子不参与这一过程, 在循环伏安法扫描过程中PMo12膜改性电极的稳定性很好。  相似文献   

11.
采用电化学方法在异电基体玻碳(GC)电极上制备了二茂铁 (Fc)-磷钼酸(PMo12)电荷转移配合 物修饰电极(Fe5PMo12/GC)。研究了该电极的电化学行为,发现其在硫酸溶液中进行伏安扫描时具有良好的稳定性,而且对酸性水溶液中的过氧化氢具有较好的电催化学原作用, 初步探讨了电催化还原机理。  相似文献   

12.
Electroactive nickel(II) hexacyanoferrate (NiHCF) thin film modified electrodes are effective potentiometric sensors for the determination of potassium ions. The NiHCF films are deposited onto glassy carbon electrodes by repetitive potential cycling in K(3)Fe(CN)(6)/NaNO(3)/Ni(NO(3))(2) solution. The modified electrodes exhibit a linear response to potassium ions in the concentration range 1x10(-3) to 2.0 mol dm(-3), with a near-Nernstian slope (45-49 mV per decade) at 25 degrees C. In the determination of potassium ion in syrups used for treatment of potassium deficiency, the NiHCF-modified electrode gave comparable results to those obtained using flame emission spectrophotometry.  相似文献   

13.
Gold nanoparticle modified indium tin oxide (ITO) film coated glass electrodes were prepared for the first time through direct electrochemical deposition from 0.5 M H2SO4 containing 0.1 mM HAuCl4. The resulting electrode surfaces were characterized with AFM. Cyclic voltammetry and linear sweep voltammetry (LSV) of arsenic(III) on the modified electrodes were performed. After optimization, a LOD of 5 +/- 0.2 ppb was obtained with 60 s deposition at -0.6 V (vs. SCE) in 1 M HNO3 using LSV.  相似文献   

14.
The growth of cobalt hexacyanoferrate (CoHCF) films on bare and Au-colloid-modified electrodes in nitrate or sulfate solutions was monitored by electrochemical quartz crystal microbalance. The average efficiency of CoHCF film growth for Au colloid modified electrodes is 23 and 12 ng cm(-2) s(-1) in KNO3 and K2SO4 solutions, respectively, while those values for the bare gold electrode are 15 and 9 ng cm(-2) s(-1), respectively. In K2SO4 solution, the apparent molar masses for the Au-colloid-modified electrode at lower and higher potential is 58.4 and 37.3 g mol(-1), respectively, which is larger than those for the bare gold electrode (51.7 and 26.3 g mol(-1), respectively). The respective results were also obtained in KNO3 solution. Furthermore, the difference of the apparent molar masses at lower and higher potential for Au-colloid-modified electrodes is smaller than that for bare gold electrodes in the same electrolyte. Additionally, the mechanism of charge propagation is dependent on different anions in electrolyte solutions at higher potentials where the second redox reaction of CoHCF occurs. Therefore, the existence of Au colloids can accelerate CoHCF film growth and weaken the effect of anions on mass transport.  相似文献   

15.
研究了掺杂多壁碳纳米管(MWNT)改性聚溴甲酚绿膜(PBG),以不同修饰方法制备了4种修饰电极,用扫描电镜、交流阻抗及循环伏安法等对电极进行表征。结果表明:4种修饰电极的电活化面积均得到明显提高,其中以层层修饰制备的聚溴甲酚绿膜/多壁碳纳米管复合膜(PBG/MWNT/GC)电极最能发挥MWNT和PBG的电活性。将电极用于8-羟基喹啉(8-HQ)电化学行为的研究,结果表明:4种修饰电极的伏安响应明显提高,且8-HQ在PBG/MWNT/GC上的氧化峰电位负移最多,峰电流最大,约为裸玻碳电极的4.5倍,电催化作用显著增强。8-HQ在PBG/MWNT/GC上电极反应的电子转移数和质子数均为1,是吸附控制的不可逆电氧化过程,氧化峰电流Ip与浓度c在4.0×10-6~3.5×10-4mol/L范围内呈良好的线性关系,r=-0.997 2,检出限(S/N=3)为1.96×10-8mol/L。PBG/MWNT/GC修饰电极可实现8-HQ的快捷、简便测定。  相似文献   

16.
Cha SK  Kasem KK  Abruña HD 《Talanta》1991,38(1):89-93
Electrodes modified with Chromotrope 2B incorporated by ion-exchange into a polycationic film of electropolymerized [Ru(v-bpy)(3)](2+) (v-bpy = 4-vinyl-4'-methyl-2,2'-bipyridyl) have been employed in the amperometric determination of copper in solution and exhibit very high sensitivity as well as linear calibration curves in the concentration range 7 x 10(-8)-1 x 10(-4)M. The effects of competing ligands, including chloride, bromide, oxalate, ammonia, acetate, citrate, borate, humic and fulvic acids, or the presence of competing metal ions such as cobalt or nickel on the uptake of copper by the modified electrodes have also been studied. The presence of competing ligands or metal ions decreases the analytical signal due to copper incorporation. The magnitude of this effect is dependent on the relative strength of coordination of the competing ligands for copper ions or of Chromotrope 2B for the competing metals, and also on the concentration of the interferents. The relevance of this work to speciation studies is discussed.  相似文献   

17.
利用循环伏安法(-0.5~2.2 V)将4-(2-吡啶偶氮)间苯二酚(PAR)电聚合修饰到玻碳电极表面,制备了聚PAR膜过氧化氢(H2O2)传感器。 并采用循环伏安法和计时安培法研究了修饰电极的电化学性质和对H2O2的响应特性。 结果表明,PAR膜修饰电极在低的电位下对H2O2具有优异的电催化还原效应。 在磷酸盐缓冲溶液中(pH=8.0)用计时安培法对H2O2进行了测定(工作电位0.45 V),响应电流与其浓度在2×10-5~1.76×10-3 mol/L范围内呈良好的线性关系,线性相关系数r=-0.999 83,检测限(S/N=3)为3 μmol/L。该修饰电极灵敏度高、稳定性好、制备简单,在H2O2的测定中对抗坏血酸、尿酸和葡萄糖有较好的抗干扰性。  相似文献   

18.
以碳纳米管(MWNTs)修饰的碳糊电极为基底电极,通过电沉积方法制备了六氰合铁酸钴(CoHCF)纳米多孔生物传感平台。考察了MWNTs对CoHCF沉积的影响,优化了CoHCF沉积的各种实验条件(0.5mol/L KCl,1 mmol/L CoCl2和0.9 mmol/L K3Fe(CN)6混合溶液,在循环伏安电压范围0~1.1 V内扫20圈,扫速100 mV/s),借助循环伏安法、交流阻抗法和扫描电镜法对修饰电极进行了表征。由于MWNTs的支撑作用,电沉积得到的CoHCF呈现出多孔结构和良好的电化学稳定性。具有纳米多孔结构的MWNTs-CoHCF薄膜能有效地促进生物小分子在电极上的电子交换,维生素B2在纳米多孔CoHCF/MWNTs上具有优异的氧化还原行为,其测定线性范围为1.2×10-7~2.6×10-7mol/L,检出限为8.9×10-8mol/L。  相似文献   

19.
C60 carboxylic acid derivatives can be readily adsorbed on the surface of nanocrystalline TiO2 film. The C60 carboxylic acids adsorbed on nanocrystalline TiO2 films act as charge‐transfer sensitizer. The electron transport from TiO2 to the C60 derivatives results in the generation of the cathodic photocurrent. The short‐circuit photocurrent of a C60 tetracarboxylic acid is 0.45 μA/cm2 under 464 nm light illumination. The photoelectric behaviour of ITO electrodes modified by the same C60 carboxylic acids is different from that of the modified TiO2 electrodes, and shows anodic photocurrent.  相似文献   

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