Authors: Sushant Kumar; Venugopal Santhanam
Addresses: Department of Chemical Engineering, Indian Institute of Science, Bangalore – 560012, India ' Department of Chemical Engineering, Indian Institute of Science, Bangalore – 560012, India
Abstract: Astriction between two closely spaced surfaces interacting through fringing electric fields is termed as electroadhesion. Polarisation-induced Coulombic attraction forces at the interface result in electroadhesion. The ability to switch on and off adhesion forces by electrical switching and absence of chemical residues upon detachment are some of the attractive features of electroadhesive devices. To avoid static discharges for ensuring safety and for generating uniform forces, a planar interdigitated pattern on an insulating surface with adjacent fingers being oppositely polarised is the preferred mode of operation for electroadhesive devices. A compliant substrate is required to ensure maximum contact that can lead to practically useful adhesive forces per unit surface area of the electrode. Till now, lithographically-patterned electrodes on polymeric substrates represent the state-of the art in terms of fabricating electroadhesive devices. Herein, we report a low-cost route for fabricating interdigitated electrodes on paper using a desktop inkjet printer, which involves alternate printing of silver salt and potassium bromide/potassium iodide solution, in conjunction with silver halide photographic development process. Typically, electrodes with spacing ≈1 mm can be routinely fabricated using a standard office desktop printer. We discovered that in samples where a fixing step was not used to remove excess silver salts, the gaps were reduced further to few hundreds of micron length scales when a high voltage is applied, which can pave the way to higher electric field strength and greater adhesion forces. The results of characterisation of these samples using FESEM, XRD, XPS, sheet resistance and shear load testing will be discussed.
Keywords: electroadhesion; polarisation; electrostatic force; latent silver; nanowires.
International Journal of Nanotechnology, 2017 Vol.14 No.9/10/11, pp.859 - 866
Received: 08 May 2021
Accepted: 12 May 2021
Published online: 25 Jun 2017 *