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71.
采用化学氧化法制备了导电聚吡咯(PPy).运用SEM和TEM表征了PPy的形貌,利用四探针技术测试了材料的电导率,对影响其电导率的因素进行了讨论,并对其导电机理进行研究.结果表明,氧化剂用量、反应温度、反应时间、掺杂剂的种类等对最终所得材料的导电性能及结构形态有较大的影响.以苯磺酸钠作掺杂剂,FeCl3/Py摩尔比为1.0,冰浴条件下,反应0.5h所得材料电导率最高,为58.82S/cm,其中以2-萘磺酸为掺杂剂所得PPy微观形貌呈现罕见的纤维状.电导率相对较高的PPy,说明其本身掺杂状况使它在氧化掺杂时随导带和价带间的能级差减小,禁带变窄,载流子移动阻力小;阴离子的掺杂和脱掺杂变得容易,因而电导率高. 相似文献
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首先对聚对苯二甲酸乙二醇酯(PET)薄膜进行氧等离子体预处理,然后通过原位化学氧化聚合法使得吡咯单体在PET薄膜表面沉积聚合,制备了聚对苯二甲酸乙二醇酯/聚吡咯(PET-PPy)复合膜。通过原子力显微镜、X射线光电子能谱仪、ζ电位测试对经不同时长的氧等离子体预处理的PET薄膜进行表征;利用扫描电子显微镜、耐磨性实验和表面电阻测试对PET-PPy复合膜磨损前后的表面形貌和电阻进行分析与表征。结果表明,氧等离子体预处理显著增强了PET-PPy复合膜界面粘附性。氧等离子体预处理使PET薄膜表面粗糙度增大、电负性显著增强。特别地,当预处理时间为120s时,薄膜表面电负性明显增强,此时PET-PPy复合膜磨损后的电阻值变化最小,表明PET薄膜与PPy功能层界面粘附强度得到明显增强。 相似文献
74.
Novel Iron/Cobalt‐Containing Polypyrrole Hydrogel‐Derived Trifunctional Electrocatalyst for Self‐Powered Overall Water Splitting 下载免费PDF全文
Jia Yang Xu Wang Bo Li Liang Ma Lei Shi Yujie Xiong Hangxun Xu 《Advanced functional materials》2017,27(17)
Development of efficient, low‐cost, and durable electrocatalysts for the oxygen reduction reaction (ORR), oxygen evolution reaction (OER), and hydrogen evolution reaction (HER) is of significant importance for many electrochemical devices, such as rechargeable metal–air batteries, fuel cells, and water electrolyzers. Here, a novel approach for the synthesis of a trifunctional electrocatalyst derived from iron/cobalt‐containing polypyrrole (PPy) hydrogel is reported. This strategy relies on the formation of a supramolecularly cross‐linked PPy hydrogel that allows for efficient and homogeneous incorporation of highly active Fe/Co–N–C species. Meanwhile, Co nanoparticles are also formed and embedded into the carbon scaffold during the pyrolysis process, further promoting electrochemical activities. The resultant electrocatalyst exhibits prominent catalytic activities for ORR, OER, and HER, surpassing previously reported trifunctional electrocatalysts. Finally, it is demonstrated that the as‐obtained trifunctional electrocatalyst can be used for electrocatalytic overall water splitting in a self‐powered manner under ambient conditions. This work offers new prospects in developing highly active, nonprecious‐metal‐based electrocatalysts in electrochemical energy devices. 相似文献
75.
为了得到新型导电聚合物/石墨烯纳米复合材料,采用偶氮染料甲基橙为掺杂剂,过硫酸铵为氧化剂,一步法制备了纳米片状的聚吡咯/氧化石墨烯复合材料,通过傅里叶红外光谱、扫描电子显微镜等测试,对聚吡咯/氧化石墨烯复合材料的结构和形貌进行表征;通过循环伏安法对其进行电化学性能测试.结果表明:由于甲基橙分子中含有的磺酸根阴离子,甲基橙分子掺杂在聚吡咯分子链中,影响了聚吡咯分子的共轭结构;在聚吡咯/氧化石墨烯复合材料中保留了氧化石墨烯的片状结构,表明吡咯单体首先被吸附到氧化石墨表面,进而在氧化石墨烯表面发生聚合.聚吡咯/氧化石墨烯复合材料均匀的片状纳米结构,在循环伏安测试中显现出具有良好的电容特性,将来可以应用到商业电容器领域. 相似文献
76.
The degradation behaviour of electrochemically prepared polythiophene and polypyrrole has been studied by thermal gravimetric
analysis technique. Studies on both the polymers show that they are more stable than polyacetylene but still undergo degradation
reactions which involve two steps, viz. loss of dopant and then degradation of polymer backbone. The general features of degradation
mechanisms are discussed. 相似文献
77.
A metallic polypyrrole film has been directly formed on a p‐type Si substrate by means of an anodization method under conditions of constant current density by an electrolyte being held at a constant temperature of 55°C that was composed of 0.40M pyrrole and 0.10M tetrabutylammonium tetrafluoroborate. An aluminum electrode was used as an ohmic contact. The polypyrrole/p‐Si/Al structure has clearly demonstrated rectifying behavior by the current–voltage curves studied at room temperature. The capacitance–voltage–frequency curves of the structure have been measured at different frequencies at room temperature in dark. To observe the effect of the aging, the measurements were also repeated 7, 15, 30, 60, and 90 days after fabrication of the polypyrrole/p‐Si/Al Schottky diode. During the whole measurement process, the probe of holder on sample was fixed to eliminate effects of surface inhomogeneity. The interface state density distribution curves of device have been obtained from forward bias current–voltage (I‐V) and capacitance–frequency (C‐f) characteristics as a function of aging time. From these curves, the exponential growth of the interface‐state density from midgap toward the top of the valence band is very apparent. The shape of the interface state density distribution curves from the forward bias I‐V characteristics are very similar to those obtained from C‐f. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 101: 2313–2319, 2006 相似文献
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PPy/SiO2纳米复合材料的合成与导电性能 总被引:6,自引:0,他引:6
以乙醚反应介质,用化学方法合成了聚吡咯纳米复合材料,利用红外光谱,四探针技术和透射镜表征了这些材料的组成,结构和导电性能,结果表明,载流子在PPy分子链之间和PPy聚集体之间有的传导性。 相似文献