Advances in the optimization of silicon-based thermoelectrics: a theory perspective

Abstract

Thermoelectric devices convert temperature gradients into electrical power and vice versa, thus enabling energy scavenging from waste heat, sensing and cooling.Yet, many of these attractive applications are hindered by the limited efficiency of thermoelectric materials, especially in the low temperature regime. This review provides a summary of the recent advances in the design of new efficient silicon-based thermoelectric materials through nanostructuring, alloying and chemical optimization, emphasizing the contribution from theory and atomistic modeling.Thermoelectric (TE) devices can be used to scavenge thermal energy, and can be combined to photovoltaics to enhance energy conversion efficiency. Peltier coolers will play an increasingly important role in active heat management at the small scale, for example in electronic devices and sensors. However, the largescale implementation of TE technology stems from improving the efficiency and the processing costs of materials. The conversion efficiency of TE materials is determined by their dimensionless figure of merit,

Reducing Kapitza resistance between graphene/water interface via interfacial superlattice structure

“…The drive to make electronic devices smaller and denser has introduced severe challenges for heat dissipation [1,2]. Therefore, thermal transport in low-dimensional materials has attracted significant recent interests [3,4].…”

Beating the Thermal Conductivity Alloy Limit Using Long-Period Compositionally Graded Si1–xGex Superlattices

“…In SLs, the crystalline quality, the period, the acoustic mismatch between the layers, the roughness of the interfaces, the chemical mixing at the interfaces, and the total thickness have significant impact on the thermal conductivity . The dependence of the cross-plane thermal conductivity on the SL period has been analyzed in a number of experimental and theoretical works. , Experimental results have shown that κ decreases with decreasing period thickness for relatively long periods, reaching a minimum value at a small period thicknesses due to the competition between coherent and incoherent phonon transport . The optimum thickness strongly depends both on the roughness of the interfaces and on the acoustic mismatch of the layers.…”