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掺杂聚乙炔的能带结构计算 被引量:1
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作者 曹阳 王友良 陈波 《Chinese Journal of Chemical Physics》 SCIE CAS CSCD 1989年第5期384-388,共5页
本文采用LCAO-SCF ab initio晶体轨道方法计算了聚乙炔和锂掺杂聚乙炔的导带和价带的能带结构,讨论了锂掺杂含量对能带结构的影响和电荷迁移的变化,以解释掺杂聚乙炔的绝缘体—导体变化过程及其导电机理。
关键词 乙炔 掺杂乙炔 能带结构
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MF_5(M=P,As,Sb)掺杂聚乙炔的能带结构和导电性能
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作者 黄宗浩 王荣顺 陈兰惠 《化学学报》 SCIE CAS CSCD 北大核心 1994年第2期122-126,共5页
本文采用EHMO晶体轨道方法计算了第五主族氟化物高掺杂聚乙炔的能带结构.通过比较它们五氟化物和六氟化物掺杂聚乙炔的能带结构参数,肯定了六氟化物为聚乙炔的有效导电掺杂剂.在进一步比较PF_6,AsF_6和SbF_6掺杂聚乙炔能带结构的基础上... 本文采用EHMO晶体轨道方法计算了第五主族氟化物高掺杂聚乙炔的能带结构.通过比较它们五氟化物和六氟化物掺杂聚乙炔的能带结构参数,肯定了六氟化物为聚乙炔的有效导电掺杂剂.在进一步比较PF_6,AsF_6和SbF_6掺杂聚乙炔能带结构的基础上,满意地解释了掺杂物电导率实验测定的次序:AsF_6>SbF_6~PF_6.最后,本文又从P,As,Sb的电负性和原子半径的角度讨论了这一次序的起因. 展开更多
关键词 MF5 掺杂乙炔 能带结构 导电性能
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前景广阔的导电高分子材料
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作者 刘宇航 盖业民 陈语诗 《艺术科技》 2016年第6期68-,共1页
物质按电学性能可以分为绝缘体、半导体、导体和超导体四类。而高分子材料大多数都属于绝缘体范围,但自从美国科学家黑格(A.J.Heeger)和麦克迪尔米德(A.G.Mac Diarmid)以及日本科学家白川英树(H.Shirakawa)与1977年发现用五氟化砷或碘... 物质按电学性能可以分为绝缘体、半导体、导体和超导体四类。而高分子材料大多数都属于绝缘体范围,但自从美国科学家黑格(A.J.Heeger)和麦克迪尔米德(A.G.Mac Diarmid)以及日本科学家白川英树(H.Shirakawa)与1977年发现用五氟化砷或碘掺杂的聚乙炔薄膜(Polyacetylene)具有金属导电的性质,电导率达到10S/m。具有金属导电特性,将传统的高分子材料不可作为电解质的说法彻底打破,这一物质的出现不仅打破了高分子材料只能作为绝缘体的传统观念,更是为低维固体电子学和分子电子学的建立打下了坚实的基础,是一座非常重要的里程碑。 展开更多
关键词 高分子材料 导电 2000年诺贝尔化学奖 掺杂乙炔
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Oxygen and nitrogen-doped metal-free carbon catalysts for hydrochlorination of acetylene 被引量:6
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作者 Tongtong Zhang Jia Zhao +3 位作者 Jiangtao Xu Jinhui Xu Xiaoxia Di Xiaonian Li 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2016年第4期484-490,共7页
Activated carbon was tested as metal-free catalyst for hydrochlorination of acetylene in order to circumvent the problem of environment pollution caused by mercury and high cost by noble metals. Oxygen-doped and nitro... Activated carbon was tested as metal-free catalyst for hydrochlorination of acetylene in order to circumvent the problem of environment pollution caused by mercury and high cost by noble metals. Oxygen-doped and nitrogen-doped activated carbons were prepared and characterized by XPS, TPD and N2 physisorption methods. The influences of the surface functional groups on the catalytic performance were discussed base on these results. Among all the samples tested, a nitrogen-doped sample, AC-n-US00, exhibited the best performance, the acety- lene conversion being 92% and vinyl chloride selectivity above 99% at 240 ~C and C2H2 hourly space velocity 30 h- 1. Moreover, the AC-n-US00 catalyst exhibited a stable performance during a 200 h test with a conversion of acetylene higher than 76% at 210 ~C at a C2H2 hourly space velocity 50 h 1. In contrary, oxygen-doped catalyst had lower catalytic activities. A linear relationship between the amount of pyrrolic-N and quaternary-N species and the catalytic activity was observed, indicating that these nitrogen-doped species might be the active sites and the key in tuning the catalytic performance. It is also found that the introduction of nitrogen species into the sample could significantly increase the adsorption amount of acetylene. The deactivation of nitrogen- doped activated carbon might be caused by the decrease of the accessibility to or the total amount of active sites. 展开更多
关键词 Acetylene hydrochlorinationActivated carbonSurface chemistryOxygenated groupNitrogen-doped
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Wheat flour-derived N-doped mesoporous carbon extrudes as an efficient support for Au catalyst in acetylene hydrochlorination 被引量:4
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作者 Jie Liu Guojun Lan +2 位作者 Yiyang Qiu Xiaolong Wang Ying Li 《Chinese Journal of Catalysis》 SCIE EI CAS CSCD 北大核心 2018年第10期1664-1671,共8页
We recently reported an N‐doped mesoporous carbon(N‐MC)extrudate,with major quaternary N species,prepared by a cheap and convenient method through direct carbonization of wheat flour with silica,which has excellent ... We recently reported an N‐doped mesoporous carbon(N‐MC)extrudate,with major quaternary N species,prepared by a cheap and convenient method through direct carbonization of wheat flour with silica,which has excellent catalytic performance in acetylene hydrochlorination.Herein,we examined the activity of Au supported on N‐MC(Au/N‐MC)and compared it with that of Au supported on nitrogen‐free mesoporous carbon(Au/MC).The acetylene conversion of Au/N‐MC was 50%at 180°C with an acetylene space velocity of 600 h–1 and VHCl/VC2H2 of 1.1,which was double the activity of Au/MC(25%).The introduced nitrogen atoms acted as anchor sites that stabilized the Au3+species and inhibited the reduction of Au3+to Au0 during the preparation of Au/N‐MC catalysts. 展开更多
关键词 Au catalyst Mercury free catalyst Acetylene hydrochlorination N doped mesoporous carbon
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