Zhenjin Wang 교수

The power supply to the sensors becomes increasingly critical as the Internet of Things (IoT) evolves. Hence, our goal is to transform ambient environmental energy in our daily lives into electrical energy and then give power to IoT sensors. In this work, we developed and manufactured functionally-graded piezocomposite using poly(vinylidene fluoride-co-trifluoroethylene) [P(VDF-TrFE)] and barium titanate (BaTiO3, BTO) particles. Functionally graded materials offer better specific strength, tough

The objective of this paper is to design and fabricate barium titanate (BTO)/epoxy composites, investigate the effect of poling conditions on their piezoelectric properties, and obtain their unsteady energy harvesting potential. The poling condition test deals with the effect of the poling conditions on the piezoelectricity of BTO/epoxy composites. The specimens are polarized by corona poling under different conditions, and their piezoelectric coefficient d 33 is measured. The distribution of th

We investigated the effects of poling conditions on the piezoelectric performance of potassium sodium niobate [(K,Na)NbO3, KNN]/polymer composites, to obtain their unsteady energy harvesting potential. KNN nanoparticle/polymer composites were designed and fabricated and the poling condition test was performed. The composites were polarized using the corona poling method for various poling conditions and then the piezoelectric coefficient d33 was measured. It was found that piezoelectricity does

Magnetostrictive materials have a wide variety of applications due to their great capability as sensors and energy-harvesting devices. However, their brittleness inhibits their applications as magnetostrictive devices. Recently, we developed a continuous magnetostrictive Fe-Co-fiber-embedded epoxy matrix composite to increase the flexibility of the material. In this study, we fabricated random magnetostrictive Fe-Co short fiber/epoxy composite sheets. It was found that the discontinuous Fe-Co fi

The exponential rate of advancement in flexible electronics and sensing technologies has enabled the detection of diverse vital signs and biomarkers with the use of exceptionally lightweight and flexible devices that affix to human skin. To support the continuous operation of these technologies and to enable them to track their multiple parameters, a flexible, self-powered energy supply unit with a high output is essential. In this work, we develop highly flexible and cost-effective three-phase

The Internet of Things (IoT) is the enabling technology for smart cities where IoT elements including sensors are operated separately from cloud services. If the IoT are fully implemented, then the number of sensors will be needed inevitably exceeds one trillion, the question lies in the need to collect energy to keep the sensors powered without resorting to the use of additional electricity from power outlets. Energy harvesting is the use of ambient energy already present in the environment, su

Haptic technology enhances digital interactions by simulating the sensation of touch through tactile feedback or vibrations. It enables users to feel more connected to devices by making interactions more natural and responsive. Despite its potential, developing soft piezoelectric actuators for haptic feedback remains challenging due to the inherent difficulty in balancing mechanical flexibility with strong piezoelectric properties. Manufacturing such actuators is further complicated by issues li

As the development of Internet of Things (IoT), the power supply to the sensors in IoT becomes more and more important. The piezoelectric material was widely studied as a material for energy harvesting devices. Our target is to design and fabricate a flexible, eco-friendly and light functionally graded piezocomposite for energy harvesting devices by polyvinylidene fluoride (PVDF) and lead-free piezoelectric particles. Two kinds of lead-free piezoelectric particles -- barium titanate (BTO) and po

With the appearance of the wearable devices and Internet of Things (IoT) sensors, energy harvesting devices are becoming more and more important. Energy harvesting is a process that captures unused ambient energy. We present the results of output voltage measurements in lead-free piezoelectric particle/polymer composites due to air-flow or temperature change. Barium titanate (BTO)/epoxy composite and potassium sodium niobate (KNN)/epoxy composite sheets were prepared. The composite specimens wer

High-strength and functional carbon-fiber-reinforced polymer (CFRP) composite materials with piezoelectric properties are essential for the development of science and technology for multifunctional structures. This review focuses on carbon-fiber-reinforced polymer piezoelectric composites that convert kinetic energy into electrical energy. First, a general description of the principles of piezoelectric composites is presented, and the development status of piezoelectric laminated CFRP composite