Non-contact mechanical stimulation sensing and high-voltage direct current conversion system utilizing liquid metals

The non-contact energy harvesting technologies are critical for microelectronic devices, especially in special scenarios such as enclosed spaces or extreme environments. Room-temperature liquid metals (LM), possessing both metallic and fluidic elastic properties, have emerged as the preferred materials for high-density integration, morphological reconfigurability, high performance stability, and stringent biocompatibility standards. Herein, we present a flexible ultrasonic energy harvesting and direct current (DC) generation system based on LM. This system relies on an interface between eutectic gallium‑indium‑tin alloy (eGaInSn) LM and silicon dioxide in the system. The device leverages the inherent properties of LM, utilizing electromechanical coupling technologies to facilitate intelligent perception, collection, and transformation of non-contact ultrasonic energy stimulation. This innovative approach culminates in a high-voltage DC output and facilitates dynamic DC power amplification without rectification circuits. The device outputs a notable voltage of up to 2.5 kV under a load in a double electrode configuration, while a single electrode design attains an exceptional open-circuit voltage ( V oc ) as high as 6 kV. This work expands the basic understanding of LM, electromechanical conversion, and force-electric coupling, leading to straightforward practices for ultrasonic energy harvesting and high-performance DC output. It also offers promising potential for future self-powered sensing systems, human-computer interfaces, arrayed broadcast group high-efficiency charging, and wearable energy solutions.