Scientists from Bengaluru-based Jawaharlal Nehru Centre for Advanced Scientific Research (JNCASR) have found a new Lead-free material which can efficiently convert waste heat to power small home equipment and automobiles.
“Thermoelectric energy conversion allows generation of electrical voltage when one end of a material is heated while keeping the other side cold. Finding an efficient material to realize this scientific principle has been a daunting task for scientists. It entails fitting in three seemingly different properties into a single material– high electrical conductivity of metals, high thermoelectric sensitivity of semiconductors, and low thermal conductivity of glasses. Most efficient thermoelectric materials developed by scientists so far use Lead (Pb) as a major constituent element, restricting their use for mass-market applications”, the ministry of science & technology explained in a press release.
The recent study, led by Prof. Kanishka Biswas, have now identified Pb-free material called Cadmium (Cd) doped Silver Antimony Telluride (AgSbTe2) which can efficiently allow recovery of electricity from ‘waste heat’ marking a paradigm shift in the thermoelectric puzzle. Also Read: Apple patent: Future devices may be built using processed titanium with anti-smudge coating
Prof. Biswas and his group doped (internally introduced) Silver Antimony Telluride with Cadmium (Cd) and used an advanced electron microscopy technique to visualize the resultant ordering of atoms in nanometer scale. The nanometer-scale atomic ordering scatters phonons that carries heat in a solid and enhances electrical transport by delocalizing the electronic state in the material.
This major breakthrough has been reported in the journal Science. Prof. Biswas is now trying to commercialize the high-performance thermoelectric materials and devices; in collaboration with TATA Steel where lots of waste heat is generated in steel power plant, the release added. Also Read: NASA’s Mars Mission: First robotic rover ‘Perseverance’ successfully lands on Red Planet