3D-Printed Ultra-Robust Surface-Doped Porous Silicone Sensors for Wearable Biomonitoring

Elham Davoodi, Hossein Montazerian, Reihaneh Haghniaz, Armin Rashidi, Samad Ahadian, Amir Sheikhi, Jun Chen, Ali Khademhosseini, Abbas S. Milani, Mina Hoorfar, Ehsan Toyserkani

Research output: Contribution to journalArticle

Abstract

Three-dimensional flexible porous conductors have significantly advanced wearable sensors and stretchable devices because of their specific high surface area. Dip coating of porous polymers with graphene is a facile, low cost, and scalable approach to integrate conductive layers with the flexible polymer substrate platforms; however, the products often suffer from nanoparticle delamination and overtime decay. Here, a fabrication scheme based on accessible methods and safe materials is introduced to surface-dope porous silicone sensors with graphene nanoplatelets. The sensors are internally shaped with ordered, interconnected, and tortuous internal geometries (i.e., triply periodic minimal surfaces) using fused deposition modeling (FDM) 3D-printed sacrificial molds. The molds were dip coated to transfer-embed graphene onto the silicone rubber (SR) surface. The presented procedure exhibited a stable coating on the porous silicone samples with long-term electrical resistance durability over ∼12 months period and high resistance against harsh conditions (exposure to organic solvents). Besides, the sensors retained conductivity upon severe compressive deformations (over 75% compressive strain) with high strain-recoverability and behaved robustly in response to cyclic deformations (over 400 cycles), temperature, and humidity. The sensors exhibited a gauge factor as high as 10 within the compressive strain range of 2-10%. Given the tunable sensitivity, the engineered biocompatible and flexible devices captured movements as rigorous as walking and running to the small deformations resulted by human pulse.

Original languageEnglish (US)
Pages (from-to)1520-1532
Number of pages13
JournalACS nano
Volume14
Issue number2
DOIs
StatePublished - Feb 25 2020

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All Science Journal Classification (ASJC) codes

  • Materials Science(all)
  • Engineering(all)
  • Physics and Astronomy(all)

Cite this

Davoodi, E., Montazerian, H., Haghniaz, R., Rashidi, A., Ahadian, S., Sheikhi, A., Chen, J., Khademhosseini, A., Milani, A. S., Hoorfar, M., & Toyserkani, E. (2020). 3D-Printed Ultra-Robust Surface-Doped Porous Silicone Sensors for Wearable Biomonitoring. ACS nano, 14(2), 1520-1532. https://doi.org/10.1021/acsnano.9b06283