Researchers at Tohoku University have developed a new thermoelectric material based on chromium nitride by incorporating small amounts of titanium. This modification increases the efficiency of converting heat into electricity by 250 times compared to pure chromium nitride. The process avoids high-temperature treatment, allowing for integration into heat-sensitive electronic devices.
The team optimized the titanium concentration, testing a range between 4.6% and 9.3%. This addition reduced the number of charge-carrying electrons but increased their mobility by nearly 100 times. Consequently, the power factor reached 5.26 micro-watts per centimeter per Kelvin squared, significantly outperforming the baseline material.
The scientists also created a prototype thermoelectric generator using the new material. It achieved a specific output power of 38.0 milliwatts per square centimeter and a maximum power of 455.8 nano-watts at a temperature difference of 96 Kelvin. This performance is comparable to existing high-efficiency thermoelectric materials.
The technology is designed for harvesting waste heat from industrial equipment, transportation, and smartphones. Since the thin films can be applied at room temperature, the material is suitable for manufacturing processes that require low-temperature environments to protect delicate electronic components.
