Tattoo-Based Wearable Electrochemical Devices: A Review

This article provides an overview of the recent advances in the field of skin-worn tattoo-based wearable electrochemical devices, including electrolyte and metabolite sensors, biofuel cells and batteries. Temporary tattoos are attractive platforms for fabricating skin-worn devices. Body-compliant wearable electrochemical devices on temporary tattoos couple highly favorable substrate-skin elasticity with an attractive electrochemical performance. For example, tattoo-based skin-like sensors can be used for real-time non-invasive analysis of key electrolytes and metabolites, leading to remarkable sensing capabilities. Continued progress has been made also towards developing skin-worn flexible energy harvesting and storage devices to power wearable health monitors and other devices. Key requirements and challenges that confront researchers in this exciting area of skin-worn electrochemical devices are discussed.