The Brief History of Thermoelectricity: Among Countless Pioneers, One Name Stands Out – Thomas Johann Seebeck   When looking at the brief history of the thermoelectric field and its many notable figures, there is one person we simply cannot overlook – Thomas Johann Seebeck. So, what exactly did he do to be remembered by all those in the thermoelectric community?   Who Was Thomas Johann Seebeck?   Thomas Johann Seebeck (German: Thomas Johann Seebeck; April 9, 1770 – December 10, 1831) was born in 1770 in Tallinn (then part of East Prussia, now the capital of Estonia). Seebeck’s father was a German of Swedish descent, and it was likely this background that led him to encourage his son to study medicine at the University of Berlin and the University of Göttingen – institutions where he himself had studied. In 1802, Seebeck earned his medical degree. However, since his research focus lay in the physics of experimental medicine, and he spent most of his life engaged in physics education and research, he is generally regarded as a physicist.   Seebeck’s Groundbreaking Experiment (1821)   In 1821, Seebeck connected two different metal wires to form a closed electrical circuit. He joined the ends of the two wires together to create a junction – and made a surprising discovery: if one junction was heated to a high temperature while the other was kept cool, a magnetic field existed around the circuit. He could hardly believe that applying heat to one junction of two metals would generate an electric current; at the time, he could only explain his finding using the concept of "thermomagnetic current" or "thermomagnetic phenomena."   Over the next two years (1822–1823), Seebeck reported his ongoing observations to the Prussian Academy of Sciences, describing his discovery as "metal magnetization caused by temperature differences."  The Misinterpretation and Correction of the Effect   While Seebeck did discover the thermoelectric effect, he misinterpreted its cause: he believed the magnetic field around the wires was due to the metal being magnetized in a specific direction by the temperature gradient, rather than the formation of an electric current. The Academy of Sciences argued that the phenomenon occurred because the temperature gradient generated an electric current, which in turn produced a magnetic field around the wires.   Seebeck was furious at this explanation. He retorted that the scientists’ judgment was clouded by the work of Hans Christian Ørsted (a pioneer in electromagnetism), so they could only explain the phenomenon using the theory that "magnetic fields are produced by electric currents" and failed to consider other possibilities. However, Seebeck himself could not explain a crucial fact: if the circuit was broken, the temperature gradient no longer produced a magnetic field around the wires.   It was not until 1823 that the Danish physicist Hans Christian Ørsted identified the phenomenon as a thermoelectric conversion effect, correcting the misinterpretation. This marked the official birth of the **Seebeck effect**. This correction underscored the importance of collaborative verification in the scientific community.   Key Takeaways from the Story   Q: What is the Seebeck effect?   A: The Seebeck effect refers to the phenomenon where, when two different conductors or semiconductors form a closed circuit, an electromotive force (known as thermoelectric EMF) is generated in the circuit if there is a temperature difference between the two junctions – and this EMF further produces an electric current. The direction of the current depends on the direction of the temperature gradient; typically, electrons at the hotter end migrate from the negative to the positive side.   Q: What are the application scenarios of the Seebeck effect?   A: Application scenarios of the Seebeck effect include power generation systems for aerospace equipment, fireplace power generation systems, and oven power generation systems, among others.