Directly transfer-printing tailored micro-supercapacitors

The emergence of smart electronics, bionic electronic skin and internet of things (IOT) inspires the relentless pursuit of advanced power source with versatile structures. Herein, we presented a cost-effective and industrially applicable transfer-printing method to directly fabricate micro-supercapacitors (MSCs) based on active carbon electrodes on various substrates. The fabricated individual MSC on PET substrate delivered a power density of 66.5 μW∙cm⁻² and a high output capacitance of 0.32 mF∙cm^-2. Notably, the output of voltage and capacitance could be readily tailored through directly transfer-printing MSC arrays with tandem and parallel connection fashions, respectively. In addition, aesthetically diverse MSCs on various substrates including medical film, cotton cloth and glass piece were further realized easily. Finally, some simple wearable electrics such as the dragon-patterned MSCs powered tattoo and cultural T-shirt as well as the flower-patterned MSCs powered smart cup were fabricated for the practical applications. Thus, transfer-printing technique can be effectively used to develop the fabrication of MSCs as unprecedented object-tailored power sources.