When thermoelectric materials come across with magnetism

Nowadays, thermoelectric materials have attracted a lot of attention as they can directly convert heat into electricity and vice versa. However, while strenuous efforts have been made, those conventional strategies are still inevitably going to meet their performance optimization limits. For this reason, brand new strategies are badly needed to achieve further enhancement. Here, the roles played by magnetism in recent advances of thermoelectric optimization are concluded. Firstly, magnetic thermoelectric materials can just be treated like other normal materials because the use of universal optimization strategies can still get good results. So, it is not a situation which is all or nothing and the tactics of using magnetism for thermoelectric optimization can coexist with other strategies. Besides, through magnetic doping, we can introduce and adjust magnetism in materials for further optimization. Magnetism provides more possibilities in thermoelectric optimization as it can directly influence the spin states in materials. Furthermore, in the form of magnetic second-phase nanoclusters, magnetism can be introduced to thermoelectric materials to conquer the dilemma that the solid solubility of many magnetic ions in thermoelectric materials is too low to have any significant effect on thermoelectric properties. Finally, when exposed to an external magnetic field, topological materials can rely on its unique band structures to optimize. Graphic Abstract