Direct writing of silver nanowire-based ink for flexible transparent capacitive touch pad

Abstract

Printed electronics is an emerging field involving the fabrication of electronic devices by the patterned deposition of material inks. For many systems, producing stable printable inks is the key challenge. In this work, the formulation of a silver nanowire-based ink for printed transparent electrode applications is described. The nanowire length and rheology of the ink are adjusted for printing, with a single layer printed film having a sheet resistance of approximately 30 Ω/, and a transmittance of 94% at 550 nm. The number of printed layers and volume per layer are optimized to get maximum transparency with good electrical conduction. A transparent capacitive touch pad, in the form of a 2×2 matrix is implemented, using this ink and with PDMS as the dielectric. The touch pad has a high degree of flexibility with a resistance variation less than 2% after 10 000 bending cycles. The formulated nanowire ink can be extended for other flexible and stretchable transparent sensing applications.

Nanoscale Electrical Investigation of Transparent Conductive Electrodes Based on Silver Nanowire Network

“…In recent years, transparent conductive electrodes (TCEs) have attracted considerable attention for their use as components of optoelectronic devices such as flexible touch screens, [1,2] flexible heaters, [3][4][5][6] touch sensors, [7] supercapacitors, [8] organic light-emitting diodes (OLEDs), [9][10][11] or thin-film solar cells. [12][13][14][15] Consequently, there is a major need to fabricate TCEs with welding, [28] laser sintering, [29] chemical treatment, [29][30][31] metal oxide coating, or reinforcing the junction by glue.…”

Silver Nanowire-Based Printable Electrothermochromic Ink for Flexible Touch-Display Applications

“…A Metallux 3 Leitz Wetzlar microscope was used for optical microscopy imaging. A custom-built arrangement was used to perform the bend test, while the resistance was measured using a Keysight U3606B multimeter . The ambient temperature in all of these experiments was lower than the critical transition temperature of the thermochromic material.…”

Optimization parameters effects on electrical conductivity of 3D printed circuits fabricated by direct ink writing method using functionalized multiwalled carbon nanotubes and polyvinyl alcohol conductive ink

“…Direct ink writing (D.I.W) method, one of the types of 3D printing technology has attracted researchers in recent years and has been recognised as an advanced fabrication technology because of the wide scope of applications in manufacturing flexible, wearable electronic circuits and components [1][2][3][4][5] e.g., printing flexible circuits [6,7], wearable electronics [8,9], super capacitors [10,11], batteries [12,13], strain sensor [14,15], energy harvesting devices [16,17], touch screens [18,19], bio sensors [20][21][22]. This D.I.W technology advances in the fabrication of complex electronic circuits by adopting pneumatic extrusion process [23][24][25] by formulating ink with controlled rheology [26][27][28].…”

“…Printability of inks is very essential in D.I.W as they determine the performance of fabricated parts. In printed electronics, conductive inks can impart flexibility [4][5][6][7][8]11,32], mechanical robustness and electrical conductivity [15][16][17][18][19]33]. Many researchers have fabricated electronic circuits by D.I.W method with printable inks which are composites of nano fillers like CNT, graphene, carbon black, silver inks and polymers like polyvinyl alcohol (PVA), polydimethylsiloxane (PDMS), polyvinylidene fluoride (PVDF), polyaniline (PANI) [11,14,15,18,22,34,35].…”

“…Hu et al printed silver coated Polysterene/PDMS based strain circuits with a high conductivity of 6 Â 10 4 S/m and proposed that electrical conductivity of printed circuits can be enhanced by decorating conductive inks with silver, gold nano particles [16]. Capacitive touch pad printed by Nitheesh et al using silver nanowire ink by D.I.W method presented the conductivity to be 8.3 Â 10 2 S/m [18].…”