Solving the Thermoelectric Trade Problem with Metallic Carbon Nanotubes

Abstract image

Semiconductors are generally regarded as much superior to metals as thermoelectric materials due to their much larger Seebeck coefficients (S). However, the maximum value S The semiconductor is usually accompanied by a miniscule electrical conductivity (σ), and therefore a thermoelectric energy factor (σ).P = S2σ) is small. Attempts to increase the energy (σ) of FermEF), On the other hand, decreases S. Between this trade relationship S And σ is a well-known dilemma in the development of high-performance thermoelectric devices based on semiconductor devices. Here we show the use of metallic carbon dioxide (CNTs) by melody EF Solve this problem, which is due to higher thermoelectric performance than semiconductor CNT. We have studied EF Attitude S, σ, and P CNT film series with systematically varied metal CNT content. In pure metal CNT films, both S And σ are monotonically increased EFConstantly reinforces P Increase in time EF. Specifically, placed in a metal CNT film, max P ∼5 times the highest purity (> 99%) of single crystal semiconductor CNT film. We attribute these high thermal properties to metallic CNTs at the same time S And σ near the first Van Hove singleton of one-dimensional conduction electrons.