Breakthrough material promises to convert waste into Watts

Bengaluru: Researchers from the Jawaharlal Nehru Centre for Advanced Scientific Research (JNCASR) in Bengaluru have developed a novel material with the potential to efficiently convert waste heat into electrical energy.

Prof Kanishka Biswas and his PhD student Vaishali Taneja from JNCASR’s New Chemistry Unit, along with other team members, synthesised ferecrystals, which exhibit exceptional thermoelectric properties.

Thermoelectricity refers to a material’s ability to generate voltage when exposed to heat.

Biswas explained that conventional materials are either good conductors of both heat and electricity (like metals) or poor conductors of both (like glass). “The challenge was to create a material that conducts electricity well, but blocks heat effectively,” he said.

The term ferecrystal means “almost-crystal”, derived from the Latin word fere (almost). Ferecrystals are composed of slightly rotated atomic layers, creating rotational disorder.

“Imagine a vertical stack of cards. If each card is rotated at a slightly different angle, it introduces disorder. This unique structure disrupts heat conduction while enhancing thermoelectric properties,” Biswas elaborated.

The twisted nature of ferecrystals makes them ideal for converting waste heat from industrial processes — such as chemical plants, steel factories, petroleum refineries, and vehicle exhausts — into electricity.

“This material has broad applications wherever combustion occurs, as 60% of energy is typically lost as heat. In off-grid areas, like villages, a thermoelectric device placed near a wood stove can generate enough power to charge a mobile phone or light a small bulb,” Biswas added.

To verify the material’s properties, the team collaborated with Prof N Ravishankar from the Indian Institute of Science (IISc), Bengaluru, for high-resolution microscopy analysis. The IISc results confirmed the intended twisted structures in the ferecrystals.

Other contributors to the study included Subarna Das, Sushmita Chandra, and Prabir Dutta from JNCASR, as well as Naveen Goyal from IISc.