A High‐Performance Wired and Wireless Dual‐Mode Droplet Nanogenerator Enabled by Laser‐Induced Microstructures

Droplet‐based triboelectric nanogenerators (D‐TENGs) have been widely explored for harvesting raindrop kinetic energy, but their practical use is limited by low electrical output and corrosion‐prone wired connections. Here, we report a laser‐treated, high‐performance wired and wireless dual‐mode droplet nanogenerator (L‐DDNG) with wireless signals triggered by breakdown discharge. To improve output performance, ultraviolet picosecond laser ablation is used to create hierarchical surface microstructures, which enhance charge trapping and retention while simultaneously increasing the water contact angle to approximately 150°. Upon droplet impact on the triboelectric surface, breakdown discharge is mainly triggered between tips on two bottom electrodes, accompanied by the emission of wireless electromagnetic signals. The device delivers an open‐circuit voltage of up to 550 V and a short‐circuit current of 1.1 mA, with a reliable wireless transmission distance of 2 m, capable for transient wireless illumination of five LEDs and capacitor charging. In addition, an integrated sensing‐actuation platform is demonstrated for autonomous response to rainfall intensity. This work establishes an effective route toward high‐performance droplet energy harvesting and self‐powered wireless droplet sensing, providing a practical strategy for intelligent environmental monitoring and industrial Internet of Things applications.