Decoding Thermoelectric Materials for Future Energy Solutions

Initially used predominantly for the conversion of waste heat into electricity, thermoelectric materials are now also employed in catalytic processes, proposing new ways to boost energy efficiency and environmental betterment.

Thermoelectric materials, essential for turning thermal energy into electrical energy and reducing waste, have extended their functionality beyond heat recovery and included catalysis, motivated by heat gradients found in nature and industry.

The swift progression of human society has spurred an exponential increase in energy demand. However, currently, the efficiency of primary energy utilization is below 40%, with the remainder being lost as waste heat. This results in considerable energy loss and intensifies environmental concerns.

As a contemporary energy material capable of directly transforming thermal energy into electrical energy, thermoelectric materials have garnered increased attention in the area of waste heat retrieval. They generate a thermoelectromotive force within the material when there is a temperature difference at the ends, resulting in the transformation of thermal energy into electrical energy.

Thermoelectric materials, in addition to their electric generator functionality, have introduced new possibilities for catalysis in the recent years. The slight temperature gradient (<100 °C) caused by widespread heat in nature and industry is sufficient to propel catalytic reactions.

This allows the repurposing of low-grade waste heat to power various processes like hydrogen production, organic synthesis, environment cleaning, and applications in biomedicine. It presents a novel approach to enhance energy usage efficiency, energy saving, emission reduction, and green catalysis.

The article depicts the operating modes of thermoelectrocatalysis (TECatal) systems, various potential application areas, and credits Science China Press. Among the potential applications, it includes hydrogen production and CO2 reduction, tumor therapy, tail gas treatment in automobiles, and window glass coating for indoor air purification.

A team from the Institute of Quantum and Sustainable Technology at Jiangsu University, having looked at the latest developments this emerging field offers, proposed the conceptual application direction of thermoelectrocatalysis (TECatal). They systematically reviewed existing thermoelectric catalytic materials and functioning modes, suggesting four main modes – hybrid structure mode, single-phase mode, P-N nanojunction mode, and thermogalvanic cell mode.

The research delves into methods to enhance the performance of thermoelectric catalytic materials by optimizing their thermoelectric properties, band engineering, microstructures, and stability. It also discusses potential future uses of these materials in areas like green energy, tumor treatment, and environmental governance, providing valuable reference points for their further development.

The study “Thermoelectrocatalysis: an emerging strategy for converting waste heat into chemical energy”, authored by Yuqiao Zhang, Shun Li, Jianming Zhang, Li-Dong Zhao, Yuanhua Lin, Weishu Liu, and Federico Rosei, was published on 25 January 2024 in the National Science Review.