Fully printed planar moisture-enabled electric generator arrays for scalable function integration

Ubiquitous moisture is of particular attraction for sustainable power generation. However, rigorous assembly procedures limit the effi-cient large-scale integration for moisture-enabled electric genera-tors (MEGs). Herein, we develop fully printed planar MEG (PMEG) arrays using modulated polycation and polyanion inks, which maxi-mize access to moisture and make it free of strict assembly and de-vice packaging. Thus, a PMEG unit (only 0.3 cm2) generates an open -circuit voltage of up to 1.1 V, along with a power density of 2.6 mW cm -2. A small piece of sheet with 200 PMEG units offers a maximum voltage of 200 V and a current of 1.3 mA. A standard power module is constructed to meet the on-demand power supply requirements of compact electronics. Furthermore, scalable and customizable PMEG arrays can be compatibly integrated with flexible circuits, as demonstrated by a fully printed self-powered functional system including PMEG arrays and energy-storage and electrochromic devices.