Proposed are a layered compound having indium and phosphide, a nanosheet that may be prepared using the same, and an electrical device including the materials. Proposed is a layered compound represented by K.sub.1-xIn.sub.yP.sub.z (0≤x≤1.0, 0.75≤y≤1.25, 1.25≤z≤1.75).

Proposed are a layered Group III-V arsenic compound, a Group III-V nanosheet that may be prepared using the same, and an electrical device including the materials. There is proposed a layered compound having a composition represented by [Formula 1] Mx-mAyAsz (Where M is at least one of Group I elements, A is at least one of Group III elements, x, y, and z are positive numbers which are determined according to stoichiometric ratios to ensure charge balance when m is 0, and 0<m<x).

An ingot includes a first surface, a second surface opposite to the first surface, and a third surface positioned along a first direction and connecting the first surface and the second surface. The ingot includes: a first pseudo single crystal region; an intermediate region containing one or more pseudo single crystal regions; and a second pseudo single crystal region. The first pseudo single crystal region, the intermediate region, and the second pseudo single crystal region are positioned adjacent sequentially in a second direction perpendicular to the first direction. In the second direction, a width of each of the first and second pseudo single crystal regions is larger than a width of the first intermediate region. Each of a boundary between the first pseudo single crystal region and the intermediate region and a boundary between the second pseudo single crystal region and the intermediate region includes a coincidence boundary.

An ingot includes a first surface, a second surface opposite to the first surface, and a third surface positioned along a first direction and connecting the first surface and the second surface. The ingot includes: a first pseudo single crystal region; an intermediate region containing one or more pseudo single crystal regions; and a second pseudo single crystal region. The first pseudo single crystal region, the intermediate region, and the second pseudo single crystal region are positioned adjacent sequentially in a second direction perpendicular to the first direction. In the second direction, a width of each of the first and second pseudo single crystal regions is larger than a width of the first intermediate region. Each of a boundary between the first pseudo single crystal region and the intermediate region and a boundary between the second pseudo single crystal region and the intermediate region includes a coincidence boundary.

Cu-based nanostructures have excellent catalytic, electronic, and plasmonic performance due to their unique chemical and physical properties. A range of Cu materials including foil, spherical nanoparticles, nanowires, and nanocubes have been explored for catalyzing CO.sub.2 electroreduction. However, practical application of the CO.sub.2 electroreduction reaction requires Cu catalysts hold a high percentage of exposed surface atoms for improved product selectivity. The present disclosure describes a high temperature reduction method to prepare Cu nanosheets with size range from about 40 nm to about 13 μm in a hydrophobic system. The purity of trioctyphosphine (TOP) plays an important role for shape-controlled synthesis of Cu nanosheets. The morphology evolution was investigated by adjusting the feeding molar ratio of TOP/Cu-tetradecylamine complex. The Cu nanosheets formed by the methods of the present disclosure have high surface area and stability in solution for more than three months. These Cu nanosheets have applications in reducing CO.sub.2 to fuels.

Cu-based nanostructures have excellent catalytic, electronic, and plasmonic performance due to their unique chemical and physical properties. A range of Cu materials including foil, spherical nanoparticles, nanowires, and nanocubes have been explored for catalyzing CO.sub.2 electroreduction. However, practical application of the CO.sub.2 electroreduction reaction requires Cu catalysts hold a high percentage of exposed surface atoms for improved product selectivity. The present disclosure describes a high temperature reduction method to prepare Cu nanosheets with size range from about 40 nm to about 13 μm in a hydrophobic system. The purity of trioctyphosphine (TOP) plays an important role for shape-controlled synthesis of Cu nanosheets. The morphology evolution was investigated by adjusting the feeding molar ratio of TOP/Cu-tetradecylamine complex. The Cu nanosheets formed by the methods of the present disclosure have high surface area and stability in solution for more than three months. These Cu nanosheets have applications in reducing CO.sub.2 to fuels.

Magnetoelectric heterostructures, and related articles, systems, and methods, are generally described.

A method for preparing an ultrathin two-dimensional (2D) monocrystalline nanosheet, the method including: 1) placing BiX.sub.3 powder where X=I, Br, or Cl in a crucible, and putting the crucible on a first heating zone of a furnace disposed at a gas inlet of a quartz tube; placing substrates covered with metal sheets on a second heating zone of the furnace disposed at a gas outlet of the quartz tube; 2) vacuumizing the quartz tube; pumping Ar gas into the quartz tube until the air pressure is 101.325 kPa; pumping a carrier gas into the quartz tube; and 3) heating and maintaining the second heating zone; heating the first heating zone for BiX.sub.3 evaporation until producing chemical reaction between BiX.sub.3 and the metal sheets, and preparing ultrathin 2D nanosheets on the substrates simultaneously; and cooling the substrate naturally to 15-30° C.

A method for preparing an ultrathin two-dimensional (2D) monocrystalline nanosheet, the method including: 1) placing BiX.sub.3 powder where X=I, Br, or Cl in a crucible, and putting the crucible on a first heating zone of a furnace disposed at a gas inlet of a quartz tube; placing substrates covered with metal sheets on a second heating zone of the furnace disposed at a gas outlet of the quartz tube; 2) vacuumizing the quartz tube; pumping Ar gas into the quartz tube until the air pressure is 101.325 kPa; pumping a carrier gas into the quartz tube; and 3) heating and maintaining the second heating zone; heating the first heating zone for BiX.sub.3 evaporation until producing chemical reaction between BiX.sub.3 and the metal sheets, and preparing ultrathin 2D nanosheets on the substrates simultaneously; and cooling the substrate naturally to 15-30° C.

Methods and wafers for low etch pit density, low slip line density, and low strain indium phosphide are disclosed and may include an indium phosphide single crystal wafer having a diameter of 4 inches or greater, having a measured etch pit density of less than 500 cm.sup.−2, and having fewer than 5 dislocations or slip lines as measured by x-ray diffraction imaging. The wafer may have a measured etch pit density of 200 cm.sup.−2 or less, or 100 cm.sup.−2 or less, or 10 cm.sup.−2 or less. The wafer may have a diameter of 6 inches or greater. An area of the wafer with a measured etch pit density of zero may at least 80% of the total area of the surface. An area of the wafer with a measured etch pit density of zero may be at least 90% of the total area of the surface.