Inductor‐Free Wireless Energy Delivery via Maxwell's Displacement Current from an Electrodeless Triboelectric Nanogenerator

TLDR

Wireless power delivery, sought for medical, security, RFID, and IoT applications, traditionally relies on induction coils or antennas. This study demonstrates a novel method that uses Maxwell’s displacement current generated by an electrodeless triboelectric nanogenerator (TENG) to harvest ambient mechanical energy for wireless power delivery. The authors fabricate a rotary electrodeless TENG with a segmented contact‑sliding structure; as the segments rotate, electric‑field leakage produces displacement current in free space that is collected by metal collectors. At a 3‑cm gap, the device delivers 7 µA cm⁻² and 65 V wirelessly, and larger or flexible versions can power LEDs, indicating a new noncontact wireless energy transmission platform for portable and wearable electronics.

Abstract

Wireless power delivery has been a dream technology for applications in medical science, security, radio frequency identification (RFID), and the internet of things, and is usually based on induction coils and/or antenna. Here, a new approach is demonstrated for wireless power delivery by using the Maxwell's displacement current generated by an electrodeless triboelectric nanogenerator (TENG) that directly harvests ambient mechanical energy. A rotary electrodeless TENG is fabricated using the contact and sliding mode with a segmented structure. Due to the leakage of electric field between the segments during relative rotation, the generated Maxwell's displacement current in free space is collected by metal collectors. At a gap distance of 3 cm, the output wireless current density and voltage can reach 7 µA cm-2 and 65 V, respectively. A larger rotary electrodeless TENG and flexible wearable electrodeless TENG are demonstrated to power light-emitting diodes (LEDs) through wireless energy delivery. This innovative discovery opens a new avenue for noncontact, wireless energy transmission for applications in portable and wearable electronics.