四氯化铂与铂氯酸掺杂聚乙炔的 X 射线光电子能谱研究  

XPS STUDIES OF PtCl_4 AND H2PtCl_6.6H_2O DOPED POLYACETYLENE

作　　者：曹镛[1] 郭可珍[1] 钱人元[1] 

机构地区：[1]中国科学院化学研究所

出　　处：《化学学报》1985年第5期425-432,共8页Acta Chimica Sinica

摘　　要：用 X 射线光电子能谱法对四氯化铂(PtCl_4)及铂氯酸(H_2PtCl_6·6H_2O)掺杂聚乙炔进行了研究.发现Pt4f 与 Cl2p 谱峰均由相距约1.5eV 的两组峰组成.Pt4f 高结合能端的组份可指认为四价铂,而低结合能端的组份为二价铂.对 Pt4f 及 Cl2p 峰积分强度的分析表明,对二价铂有:[Cl]/[pt^(2+)]=2,对四价铂有:[Cl]/[pt4^+]=6.C 1s 峰也由两个分离约1eV 的峰组成,高结合能端的强度随掺杂浓度的增加而增加.这些结果说明铂盐掺杂聚乙炔通过由高分子链向掺杂剂的电荷转移而使部份高分子链被氧化,部份四价铂盐被还原成 PtCl_2.透射电镜形态观察及选区电子衍射证明膜上存在 PtCl_2的聚集.电荷转移链段在高分子链上的分布是无规的.并由此估计了电荷转移链段上每个碳原子的电荷约为+0.2|e|.由以上结果我们推断 PtCl_4与 H_2PtCl_6·6H_2O 的电荷转移过程可由下式表达.对 PtCl_4 掺杂:2PtCl_4+2e→PtCl_6^(2-)+PtCl_2对 H_2PtCl_6掺杂:2H_2PtCl_6+2e→PtCl_6^(2-)+PtCl_2+4HCl这两种掺杂剂的对阴离子均是 PtCl_6^(2-)离子.The PtCl_4 and H_2PtCl_6·6H_2O doped polyacetylene were studied by X-ray photo-electron spectroscopy and transmition electron microscopy.We found that both Pt 4f andCl2p peaks could be resolved into two components both with a splitting of ca.1.5 eV.The higher binding energy component of Pt4f peak is attributed to Pt^(4+) and the lowerbinding energy one to Pt^(2+) species.From quantitative analysis of results of decompo-sition of both Pt4f and C12p peaks it was found that an atomic ratio of chlorine toplatinum for Pt^(2+) species is[C1]/[Pt](?)2 and that for Pt^(4+) species is [Cl]/[Pt](?)6 forboth PtCl_4 and H_2PtCl_6.6H_2O doped(CH)_x·Cls peaks could be decomposed into twocomponents separated by ca.leV.The intensity of the higher binding energy componentincreased on increasing dopant concentration.These results indicate that the platinumsalt doping proceeds through charge transfer from polyacetylene chain to platinum atomresulting in a partial reduction of Pt^(4+) to Pt^(2+) state.The existence of PtCl_2 clusters onthe surface of doped polyacetylene film was supported by TEM and electron diffractionobservations.These results indicate a random distribution of the dopant along the ma-cromolecular chain,and the charge per oarhon atom in the metallic region of dopedpolyacetylene has been estimated to be 0.2|e|.From these results the mechanisms of thePtCl_4,and H_2PtCl_6.6 H_2O doping processes in polyacetylene are clarified as follows:for PtCl_4 doping2PtCl_4+2e→PtC]_6^(2-)+PtCl_2for H_2PtCl_6·6H_2O doping2H_2PtCl_6+2e→PtCl_6^(2-)+PtCl_2+4HC1Thus the dopant anion in polyacetylene is PtCl_6^(2-) for both PtCl_4 and H_2PtCl_6·6H_2Odoping.

关 键 词：聚乙炔 Cl Pt 聚炔烃 掺杂剂 结合能 束缚能 掺杂浓度 电子衍射 透射电镜 分峰 电荷转移 电荷交换 光电子能谱 光电发射能谱 氯酸 氯化合物 

分 类 号：O64[理学—物理化学]