The present invention concerns new lithium rare earth halides that may be used as solid electrolytes or in electrochemical devices. The invention also refers to wet and dry processes for the synthesis of such lithium rare earth halides and lithium rare earth halides susceptible to be obtained by these processes.

An object of the present invention is to provide a scintillator having a high radiation stopping power, and having a shorter fluorescence decay time compared to conventional scintillators. The above object is achieved by setting the composition of a scintillator to a composition represented by General Formula (1).

Q.sub.xM.sub.yO.sub.3z  (1)

(wherein in General Formula (1), Q includes at least two or more divalent metallic elements; M includes at least Hf; and x, y, and z independently satisfy 0.5≤x≤1.5, 0.5≤y≤1.5, and 0.7≤z≤1.5, respectively).

The present invention relates to a mixed oxide of aluminium, of zirconium, of cerium, of lanthanum and optionally of at least one rare-earth metal other than cerium and lanthanum that makes it possible to prepare a catalyst that retains, after severe ageing, a good thermal stability and a good catalytic activity. The invention also relates to the process for preparing this mixed oxide and also to a process for treating exhaust gases from internal combustion engines using a catalyst prepared from this mixed oxide.

A solid ion conductor compound includes a compound represented by Formula 1:
Li.sub.6−wHf.sub.2−xM.sub.xO.sub.7−yZ.sub.y  Formula 1
where, in Formula 1, M is an element having an oxidation number of a and a is 5, 6, or a combination thereof, Z is an element having an oxidation number of −1, and 0<x<2, 0≤y≤2, and 0<w<6 and w=[(a−4)×x]+y.

The present invention aims to provide a scintillator which has a short fluorescence decay time, whose fluorescence intensity after a period of time following radiation irradiation is low, and which shows largely improved light-transmittance. A scintillator represented by the following General Formula (1), the scintillator including Zr, having a Zr content of not less than 1500 ppm by mass therein, and being a block of a sintered body. Q.sub.xM.sub.yO.sub.3z:A . . . (1) (wherein in General Formula (1), Q includes at least one or more kinds of divalent metallic elements; M includes at least Hf; and x, y, and z independently satisfy 0.5≤x≤1.5, 0.5≤y≤1.5, and 0.7≤z≤1.5, respectively).

A solid electrolyte includes an ion conductor represented by at least one of Formulae 1 to 3,
Li.sub.1+3xM1.sub.1−xO.sub.2  Formula 1
wherein, in Formula 1, M1 is a trivalent element, and 0<x<1,
L.sub.1−yM2O.sub.2−yX.sub.y  Formula 2
wherein, in Formula 2, M2 is a trivalent element, X is at least one of a halogen atom or a pseudohalogen, and 0<y<1,
Li.sub.1−z(a−3)M3.sub.1−zD.sub.zO.sub.2  Formula 3
wherein, in Formula 3, M3 is a trivalent element, D is at least one of a monovalent element to a hexavalent element, and 0<z<1.

A compound of Formula 1
Li.sub.1+(4−a)αHf.sub.2−αM.sup.a.sub.α(PO.sub.4−δ).sub.3  (1)
is disclosed, wherein M is at least one cationic element having a valence of a, wherein 0<α≤⅔, 1≤a≤4, and 0≤δ≤0.1. Also described are an electrolyte composition, a separator, a protected positive electrode, a protected negative electrode, and a lithium battery, each including the compound of Formula 1.

A lithium battery includes: a positive electrode having a positive active material; a negative electrode including lithium metal; and a solid electrolyte disposed therebetween. The solid electrolyte contains at least one oxide represented by Li.sub.4±xM.sub.1-x′M′.sub.x′O.sub.4 (Formula 1), Li.sub.4-yM″O.sub.4-yA′.sub.y (Formula 2), or Li.sub.4+4zM′″.sub.1-zO.sub.4 (Formula 3), wherein and 0≤x23 1 and 0≤x′≤1, M is a Group 4 element, and M′ is an element of Group 2, 3, 5, 12, or 13, a vacancy, or a combination thereof, with the proviso that when M is Zr, then x≠0, x′≠0 and M′ is Be, Ca, Sr, Ba, Ra, Cd, Hg, Cn, Ga, In, TI, an element of Group 3 or 5, or a combination thereof; 0≤y≤1, M″ is a Group 4 element, and A′ includes at least one halogen, with the proviso that when M″ is Zr, then y≠0; and 0<z<1, and M′″ is a Group 4 element.

Disclosed is a solid state electrolyte comprising a compound of Formula 1

Li.sub.7-.sub.a.sub.*α-(b−4)*β−xM.sup.a.sub.αLa.sub.3Hf.sub.2−βM.sup.b.sub.βO.sub.12−x−δX.sub.x   (1)

wherein

M.sup.a is a cationic element having a valence of a+;

M.sup.b is a cationic element having a valence of b+; and

X is an anion having a valence of −1,

wherein, when M.sup.a includes H, 0≤α≤5, otherwise 0≤α≤0.75, and wherein 0≤β≤1.5, 0≤x≤1.5, and (a*α+(b−4)β+x)>0, 0≤δ≤1.

An inorganic oxide of the present invention has a composition represented by General formula (1): M.sub.2LnX.sub.2(AlO.sub.4).sub.3 (where M includes Ca, Ln includes Tb, and X includes at least either one of Zr and Hf). Then, a number of Tb atoms in General formula (1) is 0.1 or more to 1 or less. Moreover, a crystal structure of the inorganic oxide is a garnet structure. A phosphor made of this inorganic oxide is capable of being excited by short-wavelength visible light, and can radiate narrow-band green light.