Patent ID: 11944011
Assignee: THE GOVERNMENT OF THE UNITED STATES OF AMERICA, AS REPRESENTED BY THE SECRETARY OF THE NAVY
Field: Materials, metallurgy (Chemistry)
Classification: CPC H  C | IPC C  H

Claim 0:
1. A method for forming a thermoelectric (TE) nanocomposite material, the method including steps of:
making or selecting a first material comprising a nanopowder of n- or p-type semiconductor nanoparticles or of X1/X2 . . . XN n˜ or p˜type semiconductor core/shell nanoparticles, where X1 is a core of the nanoparticles and X2/ . . . XN are shells surrounding the core wherein, —X2 . . .XN-1 are intermediate continuous or discontinuous layers, each shell surrounding a shell preceding it, and XN is an outer continuous or discontinuous shell;
making a porous green compact consisting of an interconnected particle network from the first material, the compact having an open porosity allowing permeation of the compact with gas or liquid;
infilling and coating all available surfaces inside the porous compact formed from the first material with at least one second material Y1, Y2, . . . YN to form a composite material of the first and second materials, at least one second material Y1, Y2, . . . YN being a semiconductor or a dielectric/insulator material and having a thermal conductivity lower than a thermal conductivity of the first material; and
sintering the formed nanocomposite material to remove residual porosity from the composite material and form a nanocomposite solid material with intimately connected p- or n-type networks and having strong chemical bonds at all interfaces;
wherein the nanocomposite solid material retains the nanostructure of the starting nanoparticles within the solid;
wherein the nanocomposite solid material maintains a percolating p- or n-type semiconductor network of the first material X1/X2 . . . XN within the solid second material; and
wherein the second material provides efficient phonon scattering so as to reduce a thermal conductivity of the nanocomposite material while maintaining electrical transport properties of the first material network.