A Single-Material Multi-Source Energy Harvester, Multifunctional Sensor, and Integrated Harvester-Sensor System-Demonstration of Concept

Single‐source energy harvesters that convert solar, thermal, or kinetic energy into electricity for small‐scale smart electronic devices and wireless sensor networks have been under development for decades. When an individual energy source is insufficient for the required electricity generation, multi‐source energy harvesting is indicated. Current technology usually combines different individual harvesters to achieve the capability of harvesting multiple energy sources simultaneously. However, this increases the overall size of the multi‐source harvester, but in microelectronics miniaturization is a critical consideration. Herein, an advanced approach is demonstrated to solve this issue. A single‐material energy harvesting/sensing device is fabricated using a (K_0.5Na_0.5)NbO_3‐Ba(Ni_0.5Nb_0.5)O_3–Δ (KNBNNO) ceramic as the sole energy‐conversion component. This single‐material component is able simultaneously to harvest or sense solar (visible light), thermal (temperature fluctuation), and kinetic (vibration) energy sources by incorporating its photovoltaic, pyroelectric, and piezoelectric effects, respectively. The interactions between different energy conversion effects, e.g., the influence of dynamic behavior on the photovoltaic effect and alternating current–direct current (AC–DC) signal trade‐offs, are assessed and discussed. This research is expected to stimulate energy‐efficient design of electronic devices by integrating both harvesting and sensing functions in the same material/component.