The present disclosure relates to novel two-dimensional halide perovskite materials, and the method of making and using the two-dimensional halide perovskite materials.

A thermoelectric module comprising nanostructured SnO and SnO.sub.2, and electrodes arranged between two electrical insulating substrates is described. The nanostructured SnO may be in the form of nanosheets and acting as p-type pillars of the module. The nanostructured SnO.sub.2 may be in the form of nanospheres and acting as n-type pillars of the module. This thermoelectric module is evaluated on the voltage, current, and power of the electricity generated once subjected to a temperature gradient.

A solid material includes a three-dimensional structure including recesses and a solid portion formed between the recesses, the three-dimensional structure adjusting a thermal conductivity of the solid material by interaction with phonons, wherein a minimum size of the solid portion between the recesses adjacent to each other in plan view of the three-dimensional structure is smaller than or equal to 100 nm, and the solid portion includes a region with a Young's modulus being smaller than or equal to 80% of a Young's modulus of a reference sample that is fabricated by using the same type of material as a material of the solid portion without forming any recesses.

An alloy is provided that consists essentially of

##STR00001##

wherein 0.06≤×≤ 0.24, 0.01 ≤y ≤0.06, 0/08≤z≤0.4, 0.9 ≤(a, b) ≤ 1.1, 0≤c≤ 0.05, 0≤d ≤ 0.05 and 0 ≤ e ≤ 0.1 and A is one or more of the elements in the group consisting of Zr, Hf, Sc, Y, La, and up to 5 atom % impurities.

An alloy is provided that consists essentially of

##STR00001##

wherein 0.06≤×≤ 0.24, 0.01 ≤y ≤0.06, 0/08≤z≤0.4, 0.9 ≤(a, b) ≤ 1.1, 0≤c≤ 0.05, 0≤d ≤ 0.05 and 0 ≤ e ≤ 0.1 and A is one or more of the elements in the group consisting of Zr, Hf, Sc, Y, La, and up to 5 atom % impurities.

A thermoelectric conversion material is composed of a compound semiconductor including a plurality of base material elements, and includes: an amorphous phase; and crystal phases having an average grain size of more than or equal to 5 nm, each of the crystal phases being in a form of a grain. The plurality of base material elements include a specific base material element that causes an increase of a band gap by increasing a concentration of the specific base material element. An atomic concentration of the specific base material element included in the crystal phases with respect to a whole of the plurality of base material elements included in the crystal phases is higher than an atomic concentration of the specific base material element included in the compound semiconductor with respect to a whole of the plurality of base material elements included in the compound semiconductor.

A thermoelectric conversion material is composed of a compound semiconductor including a plurality of base material elements, and includes: an amorphous phase; and crystal phases having an average grain size of more than or equal to 5 nm, each of the crystal phases being in a form of a grain. The plurality of base material elements include a specific base material element that causes an increase of a band gap by increasing a concentration of the specific base material element. An atomic concentration of the specific base material element included in the crystal phases with respect to a whole of the plurality of base material elements included in the crystal phases is higher than an atomic concentration of the specific base material element included in the compound semiconductor with respect to a whole of the plurality of base material elements included in the compound semiconductor.

Thermoelectric (TE) nanocomposite material that includes at least one component consisting of nanocrystals. A TE nanocomposite material in accordance with the present invention can include, but is not limited to, multiple nanocrystalline structures, nanocrystal networks or partial networks, or multi-component materials, with some components forming connected interpenetrating networks including nanocrystalline networks. The TE nanocomposite material can be in the form of a bulk solid having semiconductor nanocrystallites that form an electrically conductive network within the material. In other embodiments, the TE nanocomposite material can be a nanocomposite thermoelectric material having one network of p-type or n-type semiconductor domains and a low thermal conductivity semiconductor or dielectric network or domains separating the p-type or n-type domains that provides efficient phonon scattering to reduce thermal conductivity while maintaining the electrical properties of the p-type or n-type semiconductor.

Thermoelectric (TE) nanocomposite material that includes at least one component consisting of nanocrystals. A TE nanocomposite material in accordance with the present invention can include, but is not limited to, multiple nanocrystalline structures, nanocrystal networks or partial networks, or multi-component materials, with some components forming connected interpenetrating networks including nanocrystalline networks. The TE nanocomposite material can be in the form of a bulk solid having semiconductor nanocrystallites that form an electrically conductive network within the material. In other embodiments, the TE nanocomposite material can be a nanocomposite thermoelectric material having one network of p-type or n-type semiconductor domains and a low thermal conductivity semiconductor or dielectric network or domains separating the p-type or n-type domains that provides efficient phonon scattering to reduce thermal conductivity while maintaining the electrical properties of the p-type or n-type semiconductor.

The present disclosure relates to novel two-dimensional halide perovskite materials, and the method of making and using the two-dimensional halide perovskite materials.