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The microenergy harvesting based on magneto‐mechano‐electric (MME) coupling is an emerging technology for powering wireless Internet of Things (IoT) devices because it is capable of simultaneously harvesting magnetic field energy and mechanical energy. However, further improvement in output power of conventional cantilever‐structured MME energy harvesters has met with considerable difficulties due to the inherent, high mechanical energy loss in single‐mode operation. To solve the predicament, here, this work presents a symmetric, mechanical coupled dual‐mode MME energy harvester for restricting clamp loss and then enhancing MME coupling and output power. Under a weak AC magnetic field (Hac = 4 Oe) at 60 Hz, the MME energy harvester operating in symmetric dual‐mode can generate a peak‐peak output power of 72 mWpp (root‐mean‐square value: 9 mWRMS), a 437% enhancement over a conventional single‐mode MME energy harvester, which can even drive 160 light emitting diodes (LEDs) lighting directly. A realistic application furtherly shows that the symmetric dual‐mode MME energy harvester can successfully scavenge the magnetic field energy around a household appliance, and the generated electric power can directly drive a wireless IoT system in real time. The proposed concept of symmetric dual‐mode in this work can open new avenues for future vibration‐based energy harvesters design. [ABSTRACT FROM AUTHOR]

Multiferroic magnetoelectric (ME) composites have been continually attracting researchers' attention because of the significant potential for building functional devices. Unlike conventional ME devices under quasi-static or low-power excitation, e.g., sensors, energy harvesters, and random memories, high-power ME devices like recently proposed ME antennas will perform complex dynamic behavior. The voltage-driven nonlinearity in 1–1-typed ME resonators was reported from the perspective of frequency-response curve in our last work. Here, we described both theoretically and experimentally a previously unobserved jumping and hysteresis effect in its magnetic bias characteristic. A direct link between the bias-response and the frequency-response characteristics was also experimentally provided to analyze the origin of the nonlinear behavior in the bias-response curve. In addition, the cubic spring constant k3 was theoretically calculated and compared to qualitatively explain the difference of our obtained threshold voltage that generated the first and second jumping resonances in the dual-peak bias-response curve. In contrast to our previous research, this work reveals the loading direction of the applied magnetic bias field, which plays a significant role when we consider the selection of an optimized bias field for high-power ME devices. Moreover, the sharp jumping in the bias-response curve is also a potential for opening dimensions for ME community. [ABSTRACT FROM AUTHOR]