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Catalysts play essential roles in the chemical vapor deposition of single-wall carbon nanotubes (SWCNTs). In this article, we summarize studies on catalysts for the structure-controlled growth and mass production of SWCNTs, discussing the main progress and the remaining challenges. [ABSTRACT FROM AUTHOR]

When the size and spacing of catalyst nanoparticles are well controlled on a substrate, carbon nanotubes (CNTs) can grow and assemble into a unique, vertically aligned structure frequently called a “forest.” Long, aligned, and pure CNTs can easily be synthesized in simple or highly complex configurations. First reported in 1996, CNT forests have been shown to be unique and useful forms of CNTs, as they have spurred the development of novel processes and applications and in addition, served as test beds for investigations into CNT growth mechanisms. This article provides an overview of two decades of research in this area. [ABSTRACT FROM AUTHOR]

Aligned carbon nanotubes (CNTs) possess great potential for transforming the fabrication of advanced interfacial materials for energy and mass transport as well as for structural composites. Realizing this potential, however, requires building a deeper understanding and exercising greater control on the atomic scale physicochemical processes underlying the bottom-up synthesis and self-organization of CNTs. Hence, in situ nanoscale metrology and characterization techniques were developed for interrogating CNTs as they grow, interact, and self-assemble. This article presents an overview of recent research on characterization of CNT growth by chemical vapor deposition (CVD), organized into three categories based on the growth stage, for which each technique provides information: (I) catalyst preparation and treatment, (II) catalytic activation and CNT nucleation, and (III) CNT growth and termination. Combining all three categories together provides insights into building the process–structure relationship, and paves the way for producing tailored CNT structures having desired properties for target applications. [ABSTRACT FROM AUTHOR]

Morphologically controllable copper sulfide (CuS) nanoneedle, nanowall, and nanosheet networks on copper substrates have been fabricated by a simple, facile, and fast method based on low-temperature chemical vapor deposition through simply adjusting the reaction conditions such as the temperature and flow rate of argon gas. The compositional and structural analyses indicated that all the obtained nano-networks were single-crystalline. And their growths were possibly controlled by a solid–liquid–solid mechanism. The photocatalytic activities of the different shaped CuS nanostructures have been evaluated by their photodegradation on rhodamine B and methylene blue in aqueous phase, which revealed that in both cases the CuS nanoneedles nano-network exhibited better performance than the other two nanostructures. [ABSTRACT FROM PUBLISHER]

Diamond, because of its unique physical, chemical, and electrical properties and the feasibility of growing it in thin-film form, is an ideal choice as a material for the fabrication of reliable, long endurance, microelectromechanical/nanoelectromechanical systems (MEMS/NEMS). However, various practical challenges, including wafer-scale thickness uniformity, CMOS compatibility, surface micromachining, and, more importantly, controlling the internal stress of the diamond films, make this material more challenging for MEMS engineers. Recent advances in the growth of diamond films using chemical vapor deposition have changed this landscape since most technical hurdles have been overcome, enabling a new era of diamond-based MEMS and NEMS development. This article discusses a few examples of MEMS and NEMS devices that have been fabricated using mono-, nano-, and ultrananocrystalline diamond films as well as their performance. [ABSTRACT FROM PUBLISHER]

A novel type of fiber material for the separation of oil/water mixed liquids has been prepared by the chemical vapor deposition of hydrophobic silanes on commercially available polypropylene (PP) fiber. To achieve this, the PP fiber materials were first etched by concentrated H2SO4. Then, the as-prepared PP fiber materials were immersed in highly concentrated suspension of graphene oxide modified by amine-functionalized SiO2 nanoparticles (SiO2–GO). Finally, the as-prepared PP fiber materials were treated by the chemical vapor deposition of hydrophobic silane (octyltrichlorosilane) to form a superhydrophobic surface with a water contact angle more than 156o. The hydrophobic lightweight PP fiber materials are almost instantly filled with the oil phase when selectively absorbing oil from water. The oil can also be drained from the absorbed PP fiber materials. Moreover, the PP fiber material shows the good performance for repeated use. [ABSTRACT FROM AUTHOR]

The removal of oil spills or oily organic solvents from water surface is a great technological challenge for environmental protection. Here, a facile method to prepare superhydrophobic and superoleophilic sponge for fast and selective removal of oils from water surface has been reported. The as-prepared sponge exhibited superhydrophobic property with the water contact angle around 165°, which can be used for the absorption of oil spills or oily organic solvents. Furthermore, the resultant sponge showed good durability toward temperature. This fabrication technique is easy to grasp and to be extended. So we believe that this new functionalized sponge could be realized for the large-scale commercialized production. [ABSTRACT FROM AUTHOR]