Defect dimensionality crossover for phonon transport in thermoelectrics

With the development of modern semiconductors, new functional materials emerge continuously. The heat transport property, which is a fundamental property of solids, is attracting increasing attention. The thermal conductivity is crucial for thermoelectric materials. A reduction in the lattice thermal conductivity, i.e., the phonon transport, is an efficient approach to realize high thermoelectric performance. Lattice defects are one of the basic units of solids and can exist with various geometries and structural features. Manipulation of these features significantly affects phonon transport. This paper focuses on the defect dimensionality crossover for manipulating phonon transport in thermoelectrics and reviews the existing and potential methods for phonon-defect structure characterization, aiming to provide strategies for enhancing the performance of thermoelectric materials and the efficiency of devices.