The present disclosure relates to a positive electrode active material, a method of preparing the same, and a lithium secondary battery having a positive electrode including the same. The positive electrode active material includes: a lithium transition metal oxide particle in which a portion of Li is substituted with Na, and which includes Ni and Co atoms, wherein the lithium transition metal oxide particle includes a concentration gradient region in which the concentration of Co atoms decreases from the surface toward the center of the particle.

The present disclosure relates to a positive electrode active material, a method of preparing the same, and a lithium secondary battery having a positive electrode including the same. The positive electrode active material includes: a lithium transition metal oxide particle in which a portion of Li is substituted with Na, and which includes Ni and Co atoms, wherein the lithium transition metal oxide particle includes a concentration gradient region in which the concentration of Co atoms decreases from the surface toward the center of the particle.

An aspect of the present disclosure is a method that includes combining a first organic salt (A.sup.1X.sup.1), a first metal salt (M.sup.1(X.sup.2).sub.2), a second organic salt (A.sup.2X.sup.3), a second metal salt (M.sup.2Cl.sub.2), and a solvent to form a primary solution, where A.sup.1X.sup.1 and M.sup.1(X.sup.2).sub.2 are present in the primary solution at a first ratio between about 0.5 to 1.0 and about 1.5 to 1.0, and A.sup.2X.sup.3 to M.sup.2Cl.sub.2 are present in the primary solution at a second ratio between about 2.0 to 1.0 and about 4.0 to 1.0. In some embodiments of the present disclosure, at least one of A.sup.1 or A.sup.2 may include at least one of an alkyl ammonium, an alkyl diamine, cesium, and/or rubidium.

An aspect of the present disclosure is a method that includes combining a first organic salt (A.sup.1X.sup.1), a first metal salt (M.sup.1(X.sup.2).sub.2), a second organic salt (A.sup.2X.sup.3), a second metal salt (M.sup.2Cl.sub.2), and a solvent to form a primary solution, where A.sup.1X.sup.1 and M.sup.1(X.sup.2).sub.2 are present in the primary solution at a first ratio between about 0.5 to 1.0 and about 1.5 to 1.0, and A.sup.2X.sup.3 to M.sup.2Cl.sub.2 are present in the primary solution at a second ratio between about 2.0 to 1.0 and about 4.0 to 1.0. In some embodiments of the present disclosure, at least one of A.sup.1 or A.sup.2 may include at least one of an alkyl ammonium, an alkyl diamine, cesium, and/or rubidium.

A paramagnetic garnet-type transparent ceramic is a sintered body of complex oxide represented by the following formula (1), comprising SiO.sub.2 as a sintering aid in an amount of more than 0% by weight to 0.1% by weight or less, and has a linear transmittance of 83.5% or more at the wavelength of 1,064 nm for an optical path length of 25 mm:
(Tb.sub.1-x-yY.sub.xSc.sub.y).sub.3(Al.sub.1-zSc.sub.z).sub.5O.sub.12  (1)
wherein 0.05≤x<0.45, 0<y<0.1, 0.5<1−x−y<0.95, and 0.004<z<0.2.

A paramagnetic garnet-type transparent ceramic is a sintered body of complex oxide represented by the following formula (1), comprising SiO.sub.2 as a sintering aid in an amount of more than 0% by weight to 0.1% by weight or less, and has a linear transmittance of 83.5% or more at the wavelength of 1,064 nm for an optical path length of 25 mm:
(Tb.sub.1-x-yY.sub.xSc.sub.y).sub.3(Al.sub.1-zSc.sub.z).sub.5O.sub.12  (1)
wherein 0.05≤x<0.45, 0<y<0.1, 0.5<1−x−y<0.95, and 0.004<z<0.2.

The ferrite powder of the present invention is a ferrite powder containing a plurality of ferrite particles, wherein the ferrite particles each are a single crystal body having an average particle diameter of 1-2,000 nm, and have a polyhedron shape, and wherein the ferrite particles each contain 2.0-10.0 mass % of Sr, and 55.0-70.0 mass % of Fe.

A method for crystallizing an amorphous multicomponent ionic compound comprises applying an external stimulus to a layer of an amorphous multicomponent ionic compound, the layer in contact with an amorphous surface of a deposition substrate at a first interface and optionally, the layer in contact with a crystalline surface at a second interface, wherein the external stimulus induces an amorphous-to-crystalline phase transformation, thereby crystallizing the layer to provide a crystalline multicomponent ionic compound, wherein the external stimulus and the crystallization are carried out at a temperature below the melting temperature of the amorphous multicomponent ionic compound. If the layer is in contact with the crystalline surface at the second interface, the temperature is further selected to achieve crystallization from the crystalline surface via solid phase epitaxial (SPE) growth without nucleation.

A method for crystallizing an amorphous multicomponent ionic compound comprises applying an external stimulus to a layer of an amorphous multicomponent ionic compound, the layer in contact with an amorphous surface of a deposition substrate at a first interface and optionally, the layer in contact with a crystalline surface at a second interface, wherein the external stimulus induces an amorphous-to-crystalline phase transformation, thereby crystallizing the layer to provide a crystalline multicomponent ionic compound, wherein the external stimulus and the crystallization are carried out at a temperature below the melting temperature of the amorphous multicomponent ionic compound. If the layer is in contact with the crystalline surface at the second interface, the temperature is further selected to achieve crystallization from the crystalline surface via solid phase epitaxial (SPE) growth without nucleation.

An electronic apparatus is provided and includes a first substrate comprising a first conductive layer; a second substrate which is opposed to the first conductive layer and is separated from the first conductive layer, the second substrate including a second conductive layer, and a first hole penetrating the second substrate; and a connecting material which electrically connects the first conductive layer and the second conductive layer via the first hole, wherein the connecting material consists of a single material; and the second conductive layer is located on the second substrate on a side opposite to a side that is opposed to the first conductive layer.