Scientists have developed a new method to control the relaxation time of ferroelectric capacitors by using two-dimensional materials, thus significantly enhancing their energy storage capacity. This innovation brings a structure that improves energy density and efficiency, and is expected to make progress in high-power electronics and sustainable technology.
Sang-Hoon Bae, assistant professor of mechanical engineering and materials science at McKay School of Engineering, Washington University in St. Louis, solved the long-standing challenge of deploying ferroelectric materials in energy storage applications. In a study published in the journal Science today (April 18th), Bae and his collaborators, including Rohan Mishra, associate professor of mechanical engineering and materials science at the University of Washington, and Chuan Wang, associate professor of electrical and systems engineering, and Ross, professor of materials science and engineering at Frances Massachusetts Institute of Technology, introduced a method to control the relaxation time of ferroelectric capacitors by using 2D materials. Relaxation time is an internal material characteristic that describes the time required for charge dissipation or attenuation.
Doctor Justin S. Kim and postdoctoral researcher Sangmoon Han cooperated with Bae to develop a new 2D/3D/2D heterostructure, which can minimize energy loss while retaining the favorable material characteristics of ferroelectric 3D materials. Their method skillfully sandwiches 2D and 3D materials in thin atomic layers, and there are carefully designed chemical and non-chemical bonds between each layer. A very thin 3D core is inserted between two external 2D layers to form a stack with a thickness of only about 30 nanometers. This is about one tenth of the average virus particle size.
The 2D/3D/2D heterostructure is carefully designed and located in the best position between conductive and non-conductive, in which the semiconductor material has the best energy storage electrical properties. Through this design, Bae and his collaborators report that its energy density is 19 times higher than that of the commercially available ferroelectric capacitor, and its efficiency is over 90%, which is unprecedented.
The upstream of the capacitor industry chain is the electrode material and electrolyte material industry, and the downstream industries are mainly used in military and civilian fields. The military fields include aviation, aerospace, ships, weapons, electronic countermeasures, etc., and the civilian fields include consumer electronics, industrial control, power equipment and new energy, communication equipment, rail transit, medical electronic equipment and automotive electronics.
