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1.
在室温下用氢气泡动态模板阴极沉积法直接快速制备了由枝晶构成的三维多孔铂膜(3D PDPFs)。研究了沉积时间、电解质和基底等实验参数的影响。采用扫描电镜和X射线衍射对沉积的3D PDPFs进行了表征。3D PDPFs对甲醇电催化氧化具有高催化活性,并且该材料在吸附吡啶后具有表面增强拉曼散射(SERS)效应,其在修饰单层n-十二烷硫醇后表现出超疏水性能。该研究为3D PDPFs的制作提供了一种简单的新方法。  相似文献   

2.
刘军  周全  谢佳琦  李容 《化学通报》2019,82(11):995-1000
在室温下用氢气泡动态模板阴极沉积法直接快速制备了由枝晶够成的三维多孔铂膜(3D PDPFs)。详细研究了沉积电势、温度、时间、电解质和基底等实验参数。采用扫描电子显微镜(SEM)和X射线衍射(XRD)对沉积的3D PDPFs进行了表征。3D PDPFs展现出多种能性:相对于光滑的铂电极,对甲醇氧化的电催化活性提高,吸附吡啶的表面增强拉曼散射(SERS)信号相当强,以及该3D PDPFs修饰N-十二烷硫醇单层后的表现出超疏水性。该方法为三维PDPFS的制作提供了一种简单的新方法。  相似文献   

3.
在室温条件下采用异相催化剂催化甲酸分解制备氢气受到研究者们的极大兴趣。本研究中,由枝晶构成的三维(3D)多孔AgPd泡沫对甲酸分解析氢具有高催化活性。采用场发射扫描电子显微镜(SEM)、投射电镜(TEM)和X射线衍射(XRD)对三维多孔AgPd合金泡沫膜的形貌和结构特征进行了表征。这种高活性是由于该泡沫具有大量的活性位点,如台阶、拐角、扭结和边缘等特殊结构。除了高催化活性以外,这种合金泡沫可采用氢气泡模板法在5分钟之内快速沉积在Ti基底上,无需其他有机物的加入,制得的AgPd合金泡沫无需后处理,可以直接用来分解甲酸制氢。这种催化剂可随时控制氢气的产生,只需将合金泡沫从HCOOH+NaCOOH的混合溶液中拉出或者浸入即可。这种泡沫催化剂在水中清洗、晾干或者在H_2SO_4中扫CV就可以活化。  相似文献   

4.
采用氢气泡动态模板电沉积法制备了三维多孔Au掺杂的Pd合金泡沫膜。采用场发射扫描电子显微镜(SEM)、能量分散X射线光谱仪(EDX)、X射线衍射(XRD)和X射线光电子能谱(XPS)对三维多孔PdAu合金泡沫膜的形貌和结构特征进行了表征。由于特殊的多孔结构和电子效应,Au掺杂的PdAu合金泡沫膜与单种多孔Pd膜相比,在碱性介质中对乙醇的电氧化具有高电催化活性。  相似文献   

5.
采用氢气泡动态模板电沉积法制备了三维多孔Au掺杂的Pd合金泡沫膜。采用场发射扫描电子显微镜(SEM)、能量分散X射线光谱仪(EDX)、X射线衍射(XRD)和X射线光电子能谱(XPS)对三维多孔PdAu合金泡沫膜的形貌和结构特征进行了表征。由于特殊的多孔结构和电子效应,Au掺杂的PdAu合金泡沫膜与单种多孔Pd膜相比,在碱性介质中对乙醇的电氧化具有高电催化活性。  相似文献   

6.
采用阴极共沉积氢气泡动态模板法成功地制备了AuPt合金薄膜,这种三维分级多孔结构是由连通的枝晶壁构成。通过扫描电镜(SEM)、X射线衍射(XRD)、X射线光电子能谱(XPS)分别对泡沫膜的形貌、物相、表面组成进行了表征。结果表明:由于多孔结构、电子效应和集合效应的影响,AuPt合金对甲酸的电催化氧化表现出高催化活性。  相似文献   

7.
双金属Ag-Cu枝晶的制备及应用   总被引:1,自引:0,他引:1  
通过铜箔基体上电沉积泡沫铜结合伽尔瓦尼置换反应制备出了银-铜(Ag-Cu)纳米枝晶, 利用X射线衍射(XRD)和场发射扫描电子显微镜(FE-SEM)对枝晶的成分及形貌进行研究发现, 随着沉积过电位的增加, 铜的前驱体形貌由棒状到枝晶状, 最后发展为泡沫状, 但泡沫状的前驱体制备的Ag-Cu 枝晶却是最规整和致密的. 另外, 银离子的浓度也会影响枝晶的形貌, 一定范围内浓度的增加有利于枝晶的形成. 通过线性扫描伏安和电流-时间曲线对制备的Ag-Cu 枝晶催化性能进行表征, 在电解质溶液中, -0.25 V(相对于饱和甘汞电极(SCE))时有一个明显的双氧水(H2O2)还原峰, 这意味着Ag-Cu枝晶对H2O2的电还原具有较好的催化活性, 当该电极被用于双氧水传感器时, 电流响应快, 能在3 s 内达到稳态电流, 线性测量范围为0.1-12 mmol·L-1, 灵敏度可以达到330.36 μA·(mmol·L-1)-1·cm-2, 这点对于提高传感器的准确性非常重要.  相似文献   

8.
聚苯乙烯胶晶膜及三维有序大孔SiO2膜的制备及表征   总被引:1,自引:0,他引:1  
采用垂直沉积法组装了三维聚苯乙烯胶晶膜,并用其为模板制备了三维有序大孔(3DOM)SiO2膜.SEM观察表明,制备的胶晶膜和3DOMSiO2膜具有fcc结构,有序性很好.考察乳液浓度对胶晶膜结构的影响表明,浓度越高,胶晶膜越厚,有序性也越高,膜在30层内都能很好的粘附在载玻片上.通过调整前驱物溶液的浓度和滴加方式,可得到表面为球形或孔状的3DOM SiO2膜.  相似文献   

9.
采用氢气泡动态模板法成功地制备了多孔AuPd泡沫膜,这种三维分级多孔结构是由连通的枝晶壁构成。通过扫描电镜(SEM)、透射电镜(TEM)、X射线衍射(XRD)、X射线光电子能谱(XPS)以及电化学技术对泡沫膜进行了表征。循环伏安曲线结果表明AuPd催化剂对甲醇的电催化氧化具有高催化活性,催化活性的强弱主要是由Au:Pd之间的比率决定的。在这些AuPd催化剂里,Au_1Pd_1催化剂对甲醇的催化活性最强。  相似文献   

10.
通过在化学镀构建的三维多孔铜上电沉积锡-锌(Sn-Zn)合金, 构筑了孔径为5 μm左右的三维多孔 Sn-Zn合金电极(3D Sn-Zn), 对其形貌、 结构和性能进行了表征和测定. 结果表明, 该电极拥有高稳定性和适宜孔径的三维多孔结构, 可降低局部电流密度, 提供均匀的电场分布, 缓解了由于锌的不均匀生长而造成的粗大枝晶; 合金镀层中的Sn元素不仅可以增大析氢过电位, 增强电极的防腐蚀性能, 还可降低锌的形核势垒, 为锌的沉积提供丰富的形核位点, 促进锌在电极表面的均匀沉积, 减少枝晶的形成. 采用3D Sn-Zn电极组装的对称电池, 在0.5 mA/cm2 下可稳定循环超过1200 h, 电压滞后仅为21.3 mV; 而采用锌片(2D Zn)组装的对称电池电压滞后达到了99.2 mV, 且在循环300 h后开始出现剧烈的电压波动. 使用3D Sn-Zn电极组装的全电池在 1.8 A/g电流密度下可稳定循环2000次.  相似文献   

11.
Gold (Au) films with open interconnected macroporous walls and nanoparticles have been successfully sculptured using the hydrogen bubble dynamic template synthesis followed by a galvanic replacement reaction. Copper (Cu) films with open interconnected macroporous walls and nanoparticles were synthesized using the electrochemically generated hydrogen bubbles as a dynamic template. Then through a galvanic replacement reaction between the porous Cu sacrificial templates and KAu(CN)2 in solution, the porous Cu films were converted to porous Au films with the similar morphologies. Additional electrochemical dealloying process was introduced to remove the remaining Cu from the porous Au films. X-ray photoelectron spectroscopy (XPS), scanning electron microscopy (SEM), Energy-dispersive X-ray (EDX), X-ray diffraction (XRD) and electrochemical methods were adopted to characterize the porous Au films. The resulted porous Au films show excellent catalytic activity toward the electrooxidation of glucose. A nonenzymatic glucose sensor based on those Au film electrodes shows a linear range from 2 to 10 mM with a sensitivity of 11.8 μA cm−2 mM−1, and a detection limit of 5 μM.  相似文献   

12.
Simultaneous plasma polymerization of halocarbons (CF4 and C2F3Cl) and sputtering of metals (Au and Al) or cosputtering [Au + polytetrafluoroethylene (PTFE, Teflon)] have been performed by means of an RF (20 MHz) glow discharge excited by a planar magnetron. The optical emission spectroscopy (OES) has been used for monitoring the deposition process of metal-doped polymer films. The light emission intensity ratios of the relevant species in the plasma volume are given in connection with the characteristics of the films prepared.  相似文献   

13.
《Electroanalysis》2006,18(5):471-477
The precursor film was first formed on the Au electrode surface based on the self‐assembly of L ‐cysteine and the adsorption of gold colloidal nanoparticles (nano‐Au). Layer‐by‐layer (LBL) assembly films of toluidine blue (TB) and nano‐Au were fabricated by alternately immersing the electrode with precursor film into the solution of toluidine blue and gold colloid. Cyclic voltammetry (CV) and quartz crystal microbalance (QCM) were adopted to monitor the regular growth of {TB/Au} bilayer films. The successful assembly of {TB/Au}n films brings a new strategy for electrochemical devices to construct layer‐by‐layer assembly films of nanomaterials and low molecular weight materials. In this article, {TB/Au}n films were used as model films to fabricate a mediated H2O2 biosensor based on horseradish peroxidase, which responded rapidly to H2O2 in the linear range from 1.5×10?7 mol/L to 8.6×10?3 mol/L with a detection limit of 7.0×10?8 mol/L. Morphologies of the final assembly films were characterized with scanning probe microscopy (SPM).  相似文献   

14.
Baozhen Wang 《Talanta》2007,72(2):415-418
Multilayer thin films composed of poly(allylamine hydrochloride) (PAH) and carboxymethyl cellulose (CMC) have been prepared on the surface of a gold (Au) disk electrode by a layer-by-layer deposition of PAH and CMC and ferricyanide ions ([Fe(CN)6]3−) were confined in the film. [Fe(CN)6]3− ions can be successfully confined in the films from weakly acidic or neutral [Fe(CN)6]3− solutions, while, in basic solution, [Fe(CN)6]3− ion was not confined. The [Fe(CN)6]3− ion-confined Au electrode showed clear redox peaks in the cyclic voltammogram around 0.35 V versus Ag/AgCl. The amounts of [Fe(CN)6]3− ions confined in the films depended on the thickness of the films or the number of layers in the LbL films. The [Fe(CN)6]3− ion-confined Au electrode was used for electrocatalytic determination of ascorbic acid in the concentration range of 1-50 mM.  相似文献   

15.
The voltammetric and electrochromic behavior of two types of indium(III) hexacyanoferrate(II/III) (InHCF) films, potentiodynamically grown either on polycrystalline Au or on tin-doped indium oxide (ITO) support electrodes, are described. A new spectral feature was seen at ca. 475 nm for the InHCF films grown on Au under extended potential window (EPW) conditions, in addition to the dominant 420 nm feature described by previous authors. The 420 nm band is the sole electrochromic feature in films grown under restricted potential window (RPW) conditions. The InHCF films were also grown in the presence of TiO2 particles in the deposition bath. The resultant InHCF–TiO2 composite films showed distinctly different photoelectrochemical responses for the EPW and the RPW counterparts. X-ray phoelectron spectroscopy data showed a higher TiO2 particle uptake for the EPW films relative to their RPW counterparts, under otherwise identical growth conditions. A second film configuration built up by InHCF derivatization of a pre-formed In–TiO2 film, yielded decidedly inferior photoresponses. Mechanistic reasons for this are presented as is evidence for the dominance of two distinct forms of InHCF under the EPW growth conditions.  相似文献   

16.
Transition‐metal phosphides (TMP) prepared by atomic layer deposition (ALD) are reported for the first time. Ultrathin Co‐P films were deposited by using PH3 plasma as the phosphorus source and an extra H2 plasma step to remove excess P in the growing films. The optimized ALD process proceeded by self‐limited layer‐by‐layer growth, and the deposited Co‐P films were highly pure and smooth. The Co‐P films deposited via ALD exhibited better electrochemical and photoelectrochemical hydrogen evolution reaction (HER) activities than similar Co‐P films prepared by the traditional post‐phosphorization method. Moreover, the deposition of ultrathin Co‐P films on periodic trenches was demonstrated, which highlights the broad and promising potential application of this ALD process for a conformal coating of TMP films on complex three‐dimensional (3D) architectures.  相似文献   

17.
Noble metal-modified TiO2 films were prepared by electron beam deposition of Pt, Pd, Au and Ag on the surface of TiO2 films with diameters ranging from <1 nm to 500 nm. The morphology of the films was characterized by X-ray diffractometry (XRD), field emission scanning electron microscope (FMSEM) and transmission electron microscope (TEM). The photocatalytic capability of the films were tested and compared by degradation of methyl orange (MO) in aqueous solutions under both UV and visible light illumination.  相似文献   

18.
The electrodeposition of lead dioxide (PbO2) onto Au and Ti substrates was anodically executed at 65°C and the electrochemical characteristics and the mechanism in the PbO2 films deposition were investigated by the using an in-situ electrochemical quartz crystal microbalance, cyclic voltammogram, and chronoamperometry experiments. An X-ray diffractometer and scanning electron microscope were also used for investigation of the formed lead dioxide films onto both substrates. Considering the experimental and theoretical mass/charge ratios, PbO2 deposition on Au by applying constant potential was in excellent agreement with the theoretical value, while relatively higher values of the mass/charge ratio due to film hydration were found when Ti was used as substrate. Analysis of X-ray diffractometer and scanning electron microscope show different film structures on each substrate, especially the additional hydration of the lead dioxide film deposited on Ti leads to some structural effects, identified as Sky-Lotus PbO2.  相似文献   

19.
Nanostructured Pd thin films are directly formed on polycrystalline Pt and Au substrates in the absence of hard and soft templates by using a cyclic potential sweep technique, which is confirmed by both SEM observation and their unusual cyclic voltammetric characteristics in H2SO4 solution. Interestingly, the bimetallic electrodes obtained after the deposition of ultrathin Pd films onto Pt and Au substrates display much higher catalytic activity towards the electro-oxidation of methanol than the bulk Pt electrode. Besides, it is found that the foreign metal substrate has great influence on the electro-catalytic behavior of the Pd films.  相似文献   

20.
MnO2 films grown on nickel foam (NF) with a desirable 3D structure are investigated as electrochemical pseudocapacitor materials for potential energy storage applications. The prepared MnO2 films are characterized by X-ray diffraction, FT-IR and scanning electron microscopy. Results indicate that the products are typical hexagonal ?-MnO2 with a uniform nanorod structure. The electrochemical measurements showed that the MnO2 films with rods-like morphology have excellent electrochemical performances and its specific capacitance value as single electrode is up to 664 F g?1 at a discharge current density of 5.5 A g?1, which is higher than that of most reported corresponding materials. The specific capacitance retention ratio is 76.7% at the current density range from 5.5 to 30 A g?1. Furthermore, we found that the deposition conditions such as deposition potential and deposition mass have a pronounced effect on their electrochemical activities.  相似文献   

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