Locally Controlled Growth of Individual Lambda‐Shaped Carbon Nanofibers

Abstract

The locally defined growth of carbon nanofibers with lambda shape in an open flame process is demonstrated. Via the growth time, the geometry of the structures can be tailored to a Λor λ-type shape. Microchannel cantilever spotting and dip-pen nanolithography are utilized for the deposition of catalytic salt NiCl 2 · 6H 2 O for locally controlled growth of lambda-shaped carbon nanofibers. Rigorous downscaling reveals a critical catalytic salt volume of 0.033 µm³, resulting in exactly one lambda-shaped carbon nanofiber at a highly predefined position. An empirical model explains the observed growth process. Carbon Nanofibers www.advancedsciencenews.com

Growth, Properties, and Applications of Branched Carbon Nanostructures

“…Other technological applications for branched CNSs take advantage of aspects of their tunable properties, such as rheology [119] and hydrophobicity [5], as well as their electrical and electronic properties [8,16,18,29,120,121]. Hirtz and Hölscher et al used an open flame process to fabricate site-specific catalyst supports and also proposed an empirical model for the growth process, as shown in Figure 10, in agreement with SEM micrographs (Figure 11) [122]. A nanothickening agent for high temperature fracturing fluid in the field of oil and gas production was produced using dendritic structures obtained from the free radical polymerization of acrylamide (AM), acrylic acid (AA), sodium p-styrene sulfonate, dimethyl diallyl ammonium chloride, and MWCNTs.…”

“…Other technological applications for branched CNSs take advantage of aspects of their tunable properties, such as rheology [119] and hydrophobicity [5], as well as their electrical and electronic properties [8,16,18,29,120,121]. Hirtz and Hölscher et al used an open flame process to fabricate site-specific catalyst supports and also proposed an empirical model for the growth process, as shown in Figure 10, in agreement with SEM micrographs (Figure 11) [122].…”

Site-Specific Controlled Growth of Coiled Lambda-Shaped Carbon Nanofibers for Potential Application in Catalyst Support and Nanoelectronics

“…41 However, there are several studies using an open flame process to synthesize CNTs and CNFs as an alternative. 13,29,[42][43][44][45][46][47][48][49] These processes need less infrastructure and benefit from low process costs. Inspired by these studies we used an open ethanol flame to grow coiled lambda-shaped CNFs (cλCNFs) from NiCl 2 *6H 2 O catalysts on a substrate.…”

“…[15][16][17][18] Several approaches were presented to fabricate branched CNTs or CNFs. 5,19,28,29,[20][21][22][23][24][25][26][27] Another peculiar subset of carbon structures are wound-up CNFs/CNTs. These twisted structures are commonly referred to as coiled or helical CNFs/CNTs and are of particular interest for introducing chirality into the system.…”

“…In a previous study, we discovered a growths mode for lambda shaped CNFs (labelled ΛCNFs or λCNFs, dependent on their geometry) with two feet anchored to the growing substrate and optional a free standing head. 29 These nanostructures grow in an open…”