Transducing Thermal and Optical Energies to Motion and Electricity with Coherent-Domain Ferroelastic Materials

University Of California-Berkeley, Berkeley CA

Investigators

Abstract

Abstract "Transducing Thermal and Optical Energies to Motion and Electricity with Coherent-Domain Ferroelastic Materials" by Junqiao Wu, University of California-Berkeley Research Objectives and Approaches The objective of this program is to demonstrate a transformative technology with superior performance to transduce thermal and optical energies to mechanical motion and electricity. A training program will also be built for undergraduate and community college students through curriculum and research developments. The approach is to exploit the large spontaneous strain arising from the ferroelastic phase transition of VO2-based single-crystal microbeams. This beam is mechanically coupled with a passive clamping beam or a piezoelectric layer, forming a composite beam that bends in a tunable temperature range over which the active material undergoes the phase transition. Intellectual Merit The proposed research seeks to transform conventional thermal-optical-mechanical-electrical energy transducing technologies using innovative material systems coupling multiple functionalities with coherent domain structures. Low-grade waste heat from sources slightly above room temperature is extremely abundant. In this temperature regime (<100 Celsius), conventional technologies such as thermoelectrics become too inefficient to be practical. The proposed innovative approach is able to convert low-grade waste heat into mechanical motion and electricity at efficiencies potentially much higher than conventional technologies. Broader Impacts On the global energy diagram, more than 80% of the power is generated through thermal processes, and more than 50% of the total energy produced is lost as heat. The proposed research benefits society by enabling novel, microscale thermal actuation and waste heat recovery technologies at unprecedentedly high performance and low cost. The proposed project will broaden its impact by developing a "Materials for Energy" training program at Berkeley.