Just as an electrical switch regulates the flow of electric current, thermal switches can control the flow of heat. These switches serve as thermal control devices and are useful for thermal management applications. For example, they can be used in industries to reduce waste heat, resulting in cost and energy savings. These switches require materials whose thermal conductivity (κ) can be modulated to a large extent. This would allow the switch to have an "on" and "off" state depending on the thermal conductivity. However, such materials are rare and challenging to develop, and those that have been developed show only small reversible variations in their κ.