Zintl Phases and Their Impact on the Future of Environmentally Friendly Combustion Engines

Experts believe that as a result of increased manmade CO2 production, the Earth may soon undergo drastic changes in weather patterns, including increasing temperatures, decreases in arctic ice levels, and more powerful storms that could decimate communities across the planet. Combustion engines are a significant contributor to this crisis and were responsible for as much as sixty eight percent of the 1.54 billion metric tons of CO2 produced by the US in 2015. New technologies like hybrid-vehicles that combine both electric and combustion systems and regenerative braking systems that recapture energy when slowing a car have been developed in an effort to reduce this. However, combustion engines are still inefficient, with around 1/3 of a standard engine’s potential energy being converted to waste heat that is pumped out of the exhaust pipe. Being able to capture and convert this wasted energy into usable electricity for the many electrical systems on a typical automobile could increase energy efficiency and help create greener vehicles. Zintl phases are ideal materials for this purpose in that they can not only convert heat into electricity, but their properties can be finely tuned to increase their efficiency. Their high thermoelectric efficiency, measured by their figure of merit (zT), could help unlock a future where cars can take advantage of more than just 2/3 of the energy stored in gasoline, allowing them to run off less fuel for longer periods and thereby reduce production of CO2 worldwide. Key Words— Engine efficiency, Environmental technology, Thermoelectrics, Waste heat conversion, Zintl phases