Deji Akinwande1,Dmitry Kireev1,Neelotpala Kumar1,Nandu Koripally1
The University of Texas at Austin1
Deji Akinwande1,Dmitry Kireev1,Neelotpala Kumar1,Nandu Koripally1
The University of Texas at Austin1
Modern skin-wearable electronics (<i>skintronics</i>) reveal a notable trend towards mobile health monitoring, the Healthcare Internet of Things, and ultimately preventive medicine. Monitoring health-related electrophysiological signals, such as brain activity, heart activity, body hydration or temperature, is essential for better comprehension of human physiology. Continuous long-term monitoring of those signals from individuals of different health conditions is essential to understanding systematic health risk factors and building preventative care solutions. In this work, we utilize <i>graphene</i> and other <i>2D materials</i> such as platinum diselenide (PtSe<sub>2</sub>) and platinum ditelluride (PtTe<sub>2</sub>) to construct the thinnest elements of skintronics - electronic tattoos. The PtSe<sub>2</sub> and PtTe<sub>2</sub> e-tattoos were found to have lower sheet resistance and electrode-skin impedance compared to monolayer graphene e-tattoos. On the other hand, we also report on a substantial advancement of the classic graphene electronic tattoos by introducing graphene nanoscrolls and stacking multiple graphene monolayers. Moreover, we show that graphene tattoos can be made insusceptible to sweat by introducing microholes into their structure. Beyond the simple use of graphene tattoos as passive electronic elements, we have discovered that the semimetallic graphene film can be used as an active element when efficiently biased electrostatically via the epidermis. The body-gated graphene tattoo transistors can work as small-signal amplifiers, contributing to the development of higher-fidelity electrophysiology measurements and decreased susceptibility to movement-related artifacts.