A Li ion conductor having a composition different from a conventional composition is provided. The Li ion conductor contains at least one selected from a group Q consisting of Ga, V, and Al, Li, La and O. A part of an Li site is optionally substituted with a metal element D, a part of an La site is optionally substituted with a metal element E, and parts of Ga, V and Al sites are optionally substituted with a metal element J. A mole ratio of an amount of Li to a total amount of La, the element E, Ga, V, Al, and the element J is not lower than 8.1/5 and not higher than 9.5/5. A mole ratio of a total amount of Ga, V, and Al to a total amount of La and the element E is not lower than 1.1/3 and not higher than 2/3.

A zirconia powder in which when a stabilizer is Y.sub.2O.sub.3, a content thereof is 1.4 mol % or more and less than 2.0 mol %; when the stabilizer is Er.sub.2O.sub.3, a content thereof is 1.4 mol % or more and 1.8 mol % or less; when the stabilizer is Yb.sub.2O.sub.3, a content thereof is 1.4 mol % or more and 1.8 mol % or less; and when the stabilizer is CaO, a content thereof is 3.5 mol % or more and 4.5 mol % or less; and in a range of 10 nm or more and 200 nm or less in a pore distribution, a peak top diameter of a pore volume distribution is 20 nm or more and 120 nm or less, a pore volume is 0.2 ml/g or more and less than 0.5 ml/g, and a pore distribution width is 30 nm or more and 170 nm or less.

A zirconia powder containing a stabilizer, and having a specific surface area of 20 m.sup.2/g or more and 60 m.sup.2/g or less and a particle diameter D.sub.50 of 0.1 μm or more and 0.7 μm or less, in which in a range of 10 nm or more and 200 nm or less in a pore distribution based on a mercury intrusion method, a peak top diameter in a pore volume distribution is 20 nm or more and 85 nm or less, a pore volume is 0.2 ml/g or more and less than 0.5 ml/g, and a pore distribution width is 40 nm or more and 105 nm or less.

A dielectric composition includes dielectric particles and first segregations. The dielectric particles each include a perovskite compound represented by ABO.sub.3 as a main component. The first segregations each include at least Ba, P, and O. A molar ratio (Ba/Ti) of Ba to Ti in the first segregations is 1.20 or more.

A dielectric composition includes dielectric particles and first segregations. The dielectric particles each include a perovskite compound represented by ABO.sub.3 as a main component. The first segregations each include at least Ba, V, and O. A molar ratio (Ba/Ti) of Ba to Ti detected in the first segregations is 1.20 or more.

A dielectric composition includes dielectric particles, grain boundary phases, and segregations. The dielectric particles each include a perovskite compound represented by ABO.sub.3 as a main component. The grain boundary phases are located between the dielectric particles. The segregations exist in a part of the grain boundary phases and include at least Al, Si, and O. A molar ratio (Al/(Al+Si)) of an Al content to a total content of Al and Si in the segregations is 0.45 or more and 0.75 or less.

A multilayer electronic component includes a body including a dielectric layer and an internal electrode; and an external electrode disposed on the body and connected to the internal electrode, wherein the dielectric layer includes first and second grains, wherein the first grain has a core-shell structure including a shell having an atomic ratio of 2*Sn/(Ba+Ti+Sn) or 2*Hf/(Ba+Ti+Hf) to be 1.0% or more and 5.0% or less, and a core having an atomic ratio of 2*Sn/(Ba+Ti+Sn) and 2*Hf/(Ba+Ti+Hf) to be less than 1.0%, and the second grain has an atomic ratio of 2*Sn/(Ba+Ti+Sn) and 2*Hf/(Ba+Ti+Hf) to be less than 1.0%, and wherein an area occupied by the first grain in an entire area of the first and second grains is 28.3-82.3%.

A method for forming a sintered composition including providing a slurry precursor including a lithium-, sodium-, or magnesium-based compound; tape casting the slurry precursor to form a green tape; and sintering the green tape at a temperature in a range of 500° C. to 1350° C. for a time in a range of less than 60 min to form a sintered composition, such that the slurry precursor further includes a solvent and dispersant. The dispersant may include an amine compound, a carboxylic acid compound, or combinations, mixtures, or salts thereof.

Provided are 5-layered MXene materials having the formulas M.sub.5X.sub.4T.sub.x; (M′aM″b)X.sub.4T.sub.x (where a+b=5); and (M′.sub.aM″.sub.b).sub.5X.sub.4T.sub.x (where a+b=1). Also provided are related methods, compositions, and applications.

A dielectric ceramic composition includes a barium titanate (BaTiO.sub.3)-based base material main ingredient and an accessory ingredient, the accessory ingredient including dysprosium (Dy) and praseodymium (Pr) as first accessory ingredients. A content of the Pr satisfies 0.233 mol≤Pr≤0.699 mol, based on 100 mol of the barium titanate base material main ingredient.