Fluid dynamic lateral slicing of high tensile strength carbon nanotubes

Abstract

Lateral slicing of micron length carbon nanotubes (CNTs) is effective on laser irradiation of the materials suspended within dynamic liquid thin films in a microfluidic vortex fluidic device (VFD). The method produces sliced CNTs with minimal defects in the absence of any chemical stabilizers, having broad length distributions centred at ca 190, 160 nm and 171 nm for single, double and multi walled CNTs respectively, as established using atomic force microscopy and supported by small angle neutron scattering solution data. Molecular dynamics simulations on a bent single walled carbon nanotube (SWCNT) with a radius of curvature of order 10 nm results in tearing across the tube upon heating, highlighting the role of shear forces which bend the tube forming strained bonds which are ruptured by the laser irradiation. CNT slicing occurs with the VFD operating in both the confined mode for a finite volume of liquid and continuous flow for scalability purposes.

High‐Shear‐Imparted Tunable Fluorescence in Polyethylenimines

“…The resulting aldehydes and carboxylates could be PEI oligomers with oxidized end groups.T he result from size exclusion chromatography ( Figure S11c) on VFD-processed PEI 800 at 0.2 mL min À1 flow rate revealed the presence of smallera nd larger sized polymers in the final product relative to asr eceived PEI 800 .T his is consistentw ith oxidative chain degradation and oxidative coupling of some "sliced" PEI chains. [28] In decoupling the effect of the gas above the dynamic thin film in the VFD, hPEI was processed at 160 8Ci naf low of air, O 2 ,C O 2 andN 2 ,r espectively ( Figure 5a). Others probablyr esult from oxidation of ap ortion of the primary amine and also from chain cleavage by hydrolysis.…”

Surfactant‐free Fabrication of Fullerene C60 Nanotubules Under Shear

“…[14] Stable nanotubules, with pores of uniform size on the surface, rapidly form at room temperature using a recently developed energy efficient vortex fluidic device (VFD), which is a thin film microfluidic platform ( Figure 1). [18][19][20][21][22][23][24][25][26][27] The nucleation and growth of particles of C 60 molecules were controlled within the dynamic thin films whereby the molecules are susceptible to intense shear, depending on the rotational speed and inclination angle of the VFD. The nanotubules were fabricated within minutes of processing time in the confined mode of operation, where a defined volume of liquid is processed in the rapidly rotating tube at the preferred tilt angle (q) of 458, with the product readily collected post shearing.…”

Fabrication of Nanofiber Filtration Membranes Using Polyethylene Terephthalate (PET): A Review

“…So related to wanted condition, one of these two modes would be selected. Some other narrative researches that have been performed with the help of VFD are involved bacteria and algal cells with graphene and magnetic polymer [78][79][80], protein folding [81], exfoliating single layered graphene and hexagonal Boron Nitride (h-BN) sheets from the bulk material [82], sol-gel synthesis of silica xero gel at room temperature and the incorporation of curcumin, [83] controlling the pore size and wall thickness of mesoporous silica [84,85], fabricating toroidal arrays of SWCNTs, [86] laterally 'slicing' CNTs, [87] accelerating enzymatic reaction, [88] probing the structure of self-organized systems [89,90], biodiesel catalysis [91] and many others. According to the extra capabilities of VFD as a various reaction media compared with Spinning Disc Processors (SDPs) or Rotating Tube Processors (RTPs), VFD will be more advantageous in reaction accomplishment [92].…”