Strain-engineering the lattice thermal conductivity of 2D kagome silica

Abstract

Two-dimensional (2D) materials exhibit a significant potential for thermal management and thermoelectric energy generation due to their unique electrical and thermal transport properties that enhance performance. Their notable stretchability indicates the feasibility of employing strain engineering to optimize both electronic and thermal properties. In this study, we apply first-principles computational methods and the Boltzmann transport equation to explore the impact of strain and higher-order anharmonicity from four-phonon (4ph) scattering on the thermal conductivity (κL) of 2D silica. Our results indicate that under a small strain of 3%, κL increases due to the decrease in the phonon scattering rate and phonon phase space. However, under larger strains (8%), κL decreases significantly due to an increased phonon–phonon scattering rates. These findings provide deeper insights into the thermal transport behavior of 2D silica, paving the way for future research in strain and phonon engineering in 2D materials.