Microwave-induced high-energy sites and targeted energy transition promising for efficient energy deployment

Abstract

Diverse interactions between microwaves and irradiated media provide a solid foundation for identifying novel organization pathways for energy flow. In this study, a high-energy-site phenomenon and targeted-energy transition mechanism were identified in a particular microwave heating (MH) process. Intense discharges were observed when microwaves were imposed on irregularly sized SiC particles, producing tremendous heat that was 8-fold the amount generated in the discharge-free case. Energy efficiency was thereby greatly improved in the electricity-microwaves-effective heat transition. Meanwhile, the dispersed microwave field energy concentrated in small sites, where local temperatures could reach 2000°C– 4000°C, with the energy density reaching up to 4.0 × 10⁵ W/kg. This can be called a high-energy site phenomenon which could induce further processes or reactions enhancement by coupling effects of heat, light, and plasma. The whole process, including microwave energy concentration and intense site-energy release, shapes a targeted-energy transition mechanism that can be optimized in a controlled manner through morphology design. In particular, the discharge intensity, frequency, and high-energy sites were strengthened through the fabrication of sharp nano/microstructures, conferring twice the energy efficiency of untreated metal wires. The microwave-induced high-energy sites and targeted energy transition provide an important pathway for high-efficiency energy deployment and may lead to promising applications.

Key words： microwave discharge; high-energy sites; targeted-energy transition; morphology design; energy efficiency

Acknowledgments

This work was supported by the Natural Science Foundation of Shandong Province (Grant No. ZR2019MEE035), the Key Research and Development Plan of Shandong Province (Grant No. 2019GSF109091), the Young Scholars Program of Shandong University (Grant No. 2018WLJH75), and the International Clean Energy Talent Program (iCET 2019).

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