Na_xSb Alloy-Based Low-Frequency Mechanical Energy Harvesters for Virtual Taste Sensations

Batteries can be activated by external mechanical force and generate current, enabling a smart class of electrochemical–mechanical strain energy harvesters therefrom. Here, we have developed a Na x Sb alloy-based harvester that is able to electrochemically convert low-frequency bending or pressing mechanical energy into electrical energy. The device is designed as a flexible symmetric cell incorporating two sodiated antimony nanoflake electrodes, whose peak power and energy output are more than twice those of other sodium-alloyed electrochemical–mechanical strain energy harvesters reported. We demonstrate that the open-circuit voltage of the device is an asymptotic function of the curvature radius in the bending mode and a linear function of pressure in the pressing mode. Taking advantage of the tunability of voltage, we present a new technology that simulates various tastes by releasing low-voltage electrical signals from the harvester. This technology can not only help people with impaired taste but also be integrated into a virtual reality system to create immersive taste experiences.