近期，本课题组张敏老师和黄有超同学分别以通讯作者和第一作者在纳米能源材料及器件领域国际知名期刊Nano Energy（SCI一区，2021年IF=17.881）上发表了题为“A Mechanically Tunable Electromagnetic Wave Harvester and Dual-modal Detector based on Quasi-static van der Waals Heterojunction”的研究成果。
该研究通过对范德华接触异质结施加压力，提出并实现了机械可调的电磁能收集器件，为基于范德华接触异质结的摩擦伏特直流发电机的能量转化机制的研究提供了一个崭新的视角。该工作首次提出，基于范德华接触异质结的摩擦伏特直流发电机和单异质结整流天线的器件结构相似，因此摩擦伏特直流发电机在准静态条件下会吸收环境中的电磁能量。由于异质结电学特性受压力调控，范德华接触异质结作为电磁能收集器可以在外界压力控制下实现“开关”状态的切换。该工作所提出的设计和机理具有普遍性，并已在基于不同材料和结构制备的器件中得到验证。该电磁能收集器可直接为电容器充电、点亮LED、为低功耗反相器供电以及作为双模传感器实时探测外界电磁辐射和压力。该研究提出的机械可调的电磁能收集器在可穿戴电子设备、智能机器人和物联网等领域具有应用潜力。
Electromagnetic (EM) wave harvesting and detection have many implications for self-powered human health monitoring and robot intelligence. Heterojunction-based energy harvesters and detectors can convert various forms of energy into electricity. Here, we report a mechanically tunable electromagnetic wave harvester (EMH), operated by quasi-static contact of a metal/indium gallium zinc oxide/metal van der Waals heterojunction. The proposed EMH behaves as a rectenna responding to low-frequency signals (80–400 MHz), where the electrode works as an antenna, the heterojunction between two separated layers works as a rectifying diode, and the parallel structure works as a capacitor. It is found that the pressure on the EMH plays an important role on regulating electronic interfaces and thus the output characteristics. The two output states (on/off states) of the EMH can be reversibly controlled by mechanical pressure. The proposed design and mechanism have been verified by various materials pairings and structures, which proves their great universality. The simple-structure EMH can continuously generate DC power for 10 hours without signal attenuation. It can supply power to a capacitor, a LED and a resistive load inverter, which demonstrates its application potential as an energy source. Moreover, the EMH can work as a sensor to qualitatively detect electromagnetic waves in the ambient environment and pressure. This work has proposed a novel solution to harvest and detect electromagnetic energy by van der Waals heterojunction in a mechanically controllable way, providing new possibilities for wearable electronics, intelligent robots, and Internet of Things.
文章链接：
器件结构及其电磁响应特性
机械调控和能量收集特性
双模传感应用：电磁探测和压力感知