Effect of surfactant concentration on the evaporation-driven deposition of carbon nanotubes: from coffee-ring effect to strain sensing

Abstract

Our discovery reveals the existence of an optimum SDS/CNT concentration ratio to achieve the highest conductivity of ring deposition for strain sensing.

Geometrically-controlled evaporation-driven deposition of conductive carbon nanotube patterns on inclined surfaces

“…The weights of the CNTs and SDS were measured using an A&D HR-200 analytical balance with a precision of 0.1 mg. According to our recent work, 15 the optimum concentration ratio for SDS and CNTs to achieve the best deposition in terms of density and conductivity is 1 : 1. Considering the concentration of 0.4 wt% for both of them, the CNTs and SDS were dispersed in deionized water.…”

“…In the second case, the conductivity of the printed pattern is considerably dependent on the density of the deposited CNTs, and alignment is not as critical. 15 There is an inverse correlation between the density of the accumulated CNTs and their electrical resistance. 15…”

“…15 There is an inverse correlation between the density of the accumulated CNTs and their electrical resistance. 15…”

“…38 Considering that Marangoni eddies can lead to unexpected distributions of solute particles 39 and have a tremendous impact on the deposition, 40 this contribution benefits from the results of the previous research done by our group. Inanlu et al 15 determined an optimum surfactant concentration in which CNTs are well dispersed in the aqueous phase and the surfactant-induced Marangoni flow has the lowest impact on the deposition, so the densest ring would be achievable.…”

“…In the second case, the conductivity of the printed pattern is considerably dependent on the density of the deposited CNTs, and alignment is not as critical. 15 There is an inverse correlation between the density of the accumulated CNTs and their electrical resistance. 15 Although there has been extensive research to find a viable approach to print nanoparticles with high precision and conductivity, an unresolved challenge is how to develop a highly reproducible approach to shape the conductive tracks with the desired shape on a substrate combined with the highly efficient material usage of inkjet printing methods.…”