Scientists have discovered a new inorganic material with the lowest thermal conductivity ever
Research by the University of Liverpool has revealed a new inorganic material with the lowest thermal conductivity to date. This research is one more step towards the discovery of new thermoelectric materials important for a sustainable society.
According to Journal Science, this discovery is a leap forward in the regulation of heat flow at the atomic scale, achieved by material design. It thus offers a global vision of energy management. In addition, it will accelerate the expansion of new materials for converting heat to electricity.
The research team, led by Professor Matt Rosseinsky from the University’s Department of Chemistry and Materials Innovation Factory and Dr Jon Alaria from the University’s Physics Department and the Stephenson Institute for Renewable Energy , created the new material so that two common arrangements of atoms slow down the speed of heat through the structure of a solid.
The mechanisms responsible for the reduced heat in each of these two arrangements were identified by the researchers by measuring the thermal conductivities of two different structures, and one of them contained the desired arrangement.
These mechanisms are difficult to combine in a single material because the arrangement of atoms must be closely monitored. In the course of the research, it is expected to obtain average physical properties of the two components. With appropriate chemical interfaces between each of these different atomic arrangements, the team empirically fused a material represented by yellow and blue plaques in the image below.
This new material exhibits lower thermal conductivity than either of the parent materials with only one arrangement. This result demonstrates that the properties of the whole structure are superior to the two distinct parts.
If we assume that the thermal conductivity of steel is 1, then a titanium bar is 0.1, water and a building brick are 0.01, the new material is 0.001, and air is 0.0005.
Almost 70% of all the energy produced in the world is wasted in the form of heat. Therefore, materials with low thermal conductivity play a central role in waste reduction and are considered a clean energy source.
Professor Matt Rosseinsky said: “The material we discovered has the lowest thermal conductivity of all inorganic solids and is almost as bad a heat conductor as air itself. The implications of this discovery are important, both for basic scientific understanding and for practical applications in thermoelectric devices that recover waste heat and as thermal barrier coatings for more efficient gas turbines.
Dr Jon Alaria said: “The exciting discovery of this study is that it is possible to improve the property of a material using complementary physics concepts and an appropriate atomistic interface. Beyond heat transport, this strategy could be applied to other important fundamental physical properties such as magnetism and superconductivity, leading to low power computation and more efficient transport of electricity.