Transfer Printing of Photoactive Layer Enabling Efficient, Wearable, and Dual-Function Organic Solar Cell Modules for a Wireless Healthcare Monitoring System
While transfer-printing is a great technique for efficient film fabrication of many emerging devices on various substrates, its application in organic solar cells (OSCs) is rarely explored. Besides, it is highly challenging to fabricate a large-scale production of a “dual-function OSC module” that runs two-objective functions simultaneously in a given single system. Through comprehensive investigation on the transfer-printing feasibility of various π-conjugated organic materials, in addition to successful transfer-printed OSC and flexible OSC module, implementation of dual-function OSC modules via the transfer-printing, in which two individual sub-cell series based on dual-purpose photoactive layers are separately integrated into a single system is showcased here. Moreover, the fabrication and operation of a wearable integrated self-powered system for wireless healthcare monitoring with the wearable transfer-printed dual-function OSC module are also demonstrated. This study opens the door to fabricating OSCs with multi-objective structures via the transfer-printing technique, which enables the extra device-level values for advanced energy-related applications.