A Mesoporous Anisotropic n-Type Bi2Te3 Monolith with Low Thermal Conductivity as an Efficient Thermoelectric Material



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A mesoporous Bi2Te3 monolith with ≈20% porosity is fabricated by hot-pressing mesoporous powders. The mesostructures are able to transport carriers and scatter phonons efficiently. The reduction (≈60%) of the thermal conductivity is sufficient to compensate for the loss of electrical conductivity perpendicular to the direction of applied pressure, leading to an enhanced zT of 0.7, highest among all reported self-doped, n-type Bi2Te3 at similar temperatures.