Platinum nanoparticles supported on graphite nanofibers (GNFs) were prepared bymicrowave assistant heating polyol process. TEM images showed that microwave prepared Ptnanoparticles supported on GNFs were small and uni...Platinum nanoparticles supported on graphite nanofibers (GNFs) were prepared bymicrowave assistant heating polyol process. TEM images showed that microwave prepared Ptnanoparticles supported on GNFs were small and uniform, and the average diameter was about 3.4nm. Cyclic voltammetric test showed that Pt/GNFs exhibited very high electrocatalytic activity formethanol oxidation.展开更多
Herein, some fundamental open questions on engineering of “super” hydrogen sorption (storage) in carbonaceous nanomaterials are considered, namely: 1) on thermodynamic stability and related characteristics of some h...Herein, some fundamental open questions on engineering of “super” hydrogen sorption (storage) in carbonaceous nanomaterials are considered, namely: 1) on thermodynamic stability and related characteristics of some hydrogenated graphene layers nanostructures: relevance to the hydrogen storage problem;2) determination of thermodynamic characteristics of graphene hydrides;3) a treatment and interpretation of some recent STM, STS, HREELS/LEED, PES, ARPS and Raman spectroscopy data on hydrogensorbtion with epitaxial graphenes;4) on the physics of intercalation of hydrogen into surface graphene-like nanoblisters in pyrolytic graphite and epitaxial graphenes;5) on the physics of the elastic and plastic deformation of graphene walls in hydrogenated graphite nanofibers;6) on the physics of engineering of “super” hydrogen sorption (storage) in carbonaceous nanomaterials, in the light of analysis of the Rodriguez-Baker extraordinary data and some others. These fundamental open questions may be solved within several years.展开更多
The present analytical review is devoted to the current problem of thermodynamic stability and related thermodynamic characteristics of the following graphene layers systems: 1) double-side hydrogenated graphene of co...The present analytical review is devoted to the current problem of thermodynamic stability and related thermodynamic characteristics of the following graphene layers systems: 1) double-side hydrogenated graphene of composition CH (theoretical graphane) (Sofo et al. 2007) and experimental graphane (Elias et al. 2009);2) theoretical single-side hydrogenated graphene of composition CH;3) theoretical single-side hydrogenated graphene of composition C2H (graphone);4) experimental hydrogenated epitaxial graphene, bilayer graphene and a few layers of graphene on SiO2 or other substrates;5) experimental and theoretical single-external side hydrogenated single-walled carbon nanotubes, and experimental hydrofullerene C60H36;6) experimental single-internal side hydrogenated (up to C2H or CH composition) graphene nanoblisters with intercalated high pressure H2 gas inside them, formed on a surface of highly oriented pyrolytic graphite or epitaxial graphene under the atomic hydrogen treatment;and 7) experimental hydrogenated graphite nanofibers-multigraphene with intercalated solid H2 nano-regions of high density inside them, relevant to solving the problem of hydrogen on-board storage (Nechaev 2011-2012).展开更多
本文将氧化石墨烯(GO)分散在N,N-二甲基乙酰胺(DMAc)中,以均苯四甲酸二酐(PMDA)和二氨基二苯醚(ODA)为单体聚合成聚酰亚胺(PI)的前驱体溶液,通过静电纺丝得到平行取向的纳米纤维薄膜,经热亚胺化制得聚酰亚胺纤维。用偏振红外光谱仪测试...本文将氧化石墨烯(GO)分散在N,N-二甲基乙酰胺(DMAc)中,以均苯四甲酸二酐(PMDA)和二氨基二苯醚(ODA)为单体聚合成聚酰亚胺(PI)的前驱体溶液,通过静电纺丝得到平行取向的纳米纤维薄膜,经热亚胺化制得聚酰亚胺纤维。用偏振红外光谱仪测试C=O键在平行和垂直纤维方向的吸收强度,随着GO添加量的增加,平行纤维轴向的方向上吸收强度逐渐增强,至0.1%GO添加量达到最大值。这是由于GO通过提高静电纺丝溶液电导率,提高了PI分子链的取向程度。经炭化和石墨化,PI纤维转化为石墨纤维。石墨纤维的XRD显示(002)面间距随GO含量增加而减少,说明GO的添加提高了石墨化程度。这是因为GO诱导了石墨化过程。石墨纤维的拉曼光谱显示D峰随着GO的添加逐渐减小,表明了石墨微晶的缺陷逐渐减少。这些都是石墨纤维热导率增加的原因。通过稳态T型法测量得到的GO/PI基石墨纤维的热导率中,0.1%GO含量对应于最高的热导率,达到331 W m−1 K−1。本文发现极少量GO(0.1%)就可以显著提高PI基石墨纳米纤维的热导率,该方法具备巨大的应用潜力。展开更多
基金This work was supported by the National Natural Science Foundation of China(No.50171063,20003009)Zhejang Provincial Natural Science Foundation(No.200053).
文摘Platinum nanoparticles supported on graphite nanofibers (GNFs) were prepared bymicrowave assistant heating polyol process. TEM images showed that microwave prepared Ptnanoparticles supported on GNFs were small and uniform, and the average diameter was about 3.4nm. Cyclic voltammetric test showed that Pt/GNFs exhibited very high electrocatalytic activity formethanol oxidation.
文摘Herein, some fundamental open questions on engineering of “super” hydrogen sorption (storage) in carbonaceous nanomaterials are considered, namely: 1) on thermodynamic stability and related characteristics of some hydrogenated graphene layers nanostructures: relevance to the hydrogen storage problem;2) determination of thermodynamic characteristics of graphene hydrides;3) a treatment and interpretation of some recent STM, STS, HREELS/LEED, PES, ARPS and Raman spectroscopy data on hydrogensorbtion with epitaxial graphenes;4) on the physics of intercalation of hydrogen into surface graphene-like nanoblisters in pyrolytic graphite and epitaxial graphenes;5) on the physics of the elastic and plastic deformation of graphene walls in hydrogenated graphite nanofibers;6) on the physics of engineering of “super” hydrogen sorption (storage) in carbonaceous nanomaterials, in the light of analysis of the Rodriguez-Baker extraordinary data and some others. These fundamental open questions may be solved within several years.
文摘The present analytical review is devoted to the current problem of thermodynamic stability and related thermodynamic characteristics of the following graphene layers systems: 1) double-side hydrogenated graphene of composition CH (theoretical graphane) (Sofo et al. 2007) and experimental graphane (Elias et al. 2009);2) theoretical single-side hydrogenated graphene of composition CH;3) theoretical single-side hydrogenated graphene of composition C2H (graphone);4) experimental hydrogenated epitaxial graphene, bilayer graphene and a few layers of graphene on SiO2 or other substrates;5) experimental and theoretical single-external side hydrogenated single-walled carbon nanotubes, and experimental hydrofullerene C60H36;6) experimental single-internal side hydrogenated (up to C2H or CH composition) graphene nanoblisters with intercalated high pressure H2 gas inside them, formed on a surface of highly oriented pyrolytic graphite or epitaxial graphene under the atomic hydrogen treatment;and 7) experimental hydrogenated graphite nanofibers-multigraphene with intercalated solid H2 nano-regions of high density inside them, relevant to solving the problem of hydrogen on-board storage (Nechaev 2011-2012).
文摘本文将氧化石墨烯(GO)分散在N,N-二甲基乙酰胺(DMAc)中,以均苯四甲酸二酐(PMDA)和二氨基二苯醚(ODA)为单体聚合成聚酰亚胺(PI)的前驱体溶液,通过静电纺丝得到平行取向的纳米纤维薄膜,经热亚胺化制得聚酰亚胺纤维。用偏振红外光谱仪测试C=O键在平行和垂直纤维方向的吸收强度,随着GO添加量的增加,平行纤维轴向的方向上吸收强度逐渐增强,至0.1%GO添加量达到最大值。这是由于GO通过提高静电纺丝溶液电导率,提高了PI分子链的取向程度。经炭化和石墨化,PI纤维转化为石墨纤维。石墨纤维的XRD显示(002)面间距随GO含量增加而减少,说明GO的添加提高了石墨化程度。这是因为GO诱导了石墨化过程。石墨纤维的拉曼光谱显示D峰随着GO的添加逐渐减小,表明了石墨微晶的缺陷逐渐减少。这些都是石墨纤维热导率增加的原因。通过稳态T型法测量得到的GO/PI基石墨纤维的热导率中,0.1%GO含量对应于最高的热导率,达到331 W m−1 K−1。本文发现极少量GO(0.1%)就可以显著提高PI基石墨纳米纤维的热导率,该方法具备巨大的应用潜力。
