Showing papers by "Weizhong Qian published in 2006"
TL;DR: In this paper, carbon nanotubes (CNTs) with totally hollow channels and/or totally filled copper nanowires have been fabricated by methane decomposition using copper microgrid as a catalyst at 1173 K.
Abstract: Carbon nanotubes (CNTs) with totally hollow channels and/or totally filled copper nanowires have been fabricated by methane decomposition using copper microgrid as a catalyst at 1173 K. The formation mechanism of CNTs with totally hollow channels is carbon precipitation at carbon-metal interface via the preferable surface diffusion mode of carbon. The selectivity of these CNTs can be improved by increasing the purity of copper catalysts and adding hydrogen in the feed gas. To form long and continuous copper nanowires up to 8–10 μm the filling of copper in the CNT channel requires the liquid or quasi-liquid state capillary adsorption of nanosized copper at 1173 K under the thermal driving force. The filling volume ratio of copper to total nano-channel of the CNTs is firstly increased to about 50%. The copper inside the CNTs is of single crystalline form and face centered cubic (fcc) structure. The method is useful for further controlled synthesis of CNTs with totally hollow channels and/or totally copper filled nanowires.
21 citations
TL;DR: In this paper, dispersed ZrO 2 nano-laminae were synthesized at low temperature using zirconium oxynitrate and polyvinyl pyrrolidone (PVP) as reaction materials.
7 citations
Patent•
27 Dec 2006
TL;DR: In this paper, an aerogel carbon nanometer pipe and preparing method and application in the new typed nanometer material preparing technological domain, which is composed of dispersed carbon nanometers pipe or carbon nanometry pipe beam, wherein the diameter of carbon nanometers pipe or pipe beam is between 1 nm and 100 um with long diameter between 101 and 106 and piling density between 0.1 and 100g/L.
Abstract: The invention discloses an aerogel carbon nanometer pipe and preparing method and application in the new typed nanometer material preparing technological domain, which is composed of dispersed carbon nanometer pipe or carbon nanometer pipe beam, wherein the diameter of carbon nanometer pipe or carbon nanometer pipe beam is between 1 nm and 100 um with long diameter between 101 and 106 and piling density between 0.1 and 100g/L. the preparing method comprises the following steps: grinding sample of carbon nanometer pipe beam or array through force; dispersing in the gas phase; sedimenting; grading to collect product. The invention can be heat and electric conductive material or organic macromolecular, inorganic, metal base, which improves dynamical toughness.
4 citations