In general, according to one embodiment, there is provided an active material. The active material contains a composite oxide having an orthorhombic crystal structure. The composite oxide is represented by a general formula of Li.sub.xM1.sub.1yM2.sub.yTi.sub.6zM3.sub.zO.sub.14+. In the general formula, M1 is at least one selected from the group consisting of Sr, Ba, Ca, and Mg; M2 is at least one selected from the group consisting of Cs, K, and Na; M3 is at least one selected from the group consisting of Al, Fe, Zr, Sn, V, Nb, Ta, and Mo; and x is within a range of 2x6, y is within a range of 0<y<1, z is within a range of 0<z6, and is within a range of 0.50.5.

A coated substrate is provided that comprises: a substrate; and a barrier coating comprising a compound having the formula: Ln.sub.2ABO.sub.8, where Ln comprises scandium, yttrium, lanthanum, cerium, praseodymium, neodymium, promethium, samarium, europium, gadolinium, terbium, dysprosium, holmium, erbium, thulium, ytterbium, lutetium, or mixtures thereof; A comprises Si, Ti, Ge, Sn, Ce, Hf, Zr, or a combination thereof; and B comprises Mo, W, or a combination thereof. In one embodiment, B comprises Mo. A gas turbine is also provided that comprises the coated substrate described above.

A method for positive electrode active material for a secondary battery includes preparing a precursor by reacting a nickel raw material, a cobalt raw material and an M1 raw material; forming a first surface-treated layer including an oxide of Formula 2 below, on a surface of a core including a lithium composite metal oxide of Formula 1 below, by mixing the precursor with a lithium raw material and an M3 raw material, firing the resultant mixture; and forming a second surface-treated layer including a lithium compound of Formula 3 below, on the core with the first surface-treated layer formed thereon,

Li.sub.aNi.sub.1xyCo.sub.xM1.sub.yM3.sub.zM2.sub.wO.sub.2 [Formula 1]

Li.sub.mM4O.sub.(m+n)/2 [Formula 2]

Li.sub.pM5.sub.qA.sub.r [Formula 3]

wherein, in Formulae 1 to 3, A, M1 to M5, a, x, y, z, w, m, n, p, and q are the same as those defined in the specification.

The invention relates to a method for producing a mixed oxide material containing the elements molybdenum, vanadium, niobium and tellurium, comprising the following steps: a) producing a mixture from starting compounds containing molybdenum, vanadium, niobium and a tellurium-containing starting compound, present in the tellurium in the +4 oxidation state, b) hydrothermal treatment of the mixture from starting compounds at a temperature of between 100 C. to 300 C., in order to obtain a product suspension, c) separating off and drying the solid material from the product suspension obtained in step b), d) activating the solid material in inert gas in order to obtain the mixed oxide material. The invention is characterized in that the tellurium-containing starting compound has a particle size D.sub.90 of less than 100 m.

A method for the production of 1T-transition metal dichalcogenide few-layer nanosheets and/or monolayer nanosheets comprising electrochemical intercalation of lithium ions into a negative electrode comprising a bulk 2H-transition metal dichalcogenide to provide an intercalated electrode, and an exfoliation step comprising contacting the intercalated electrode with a protic solvent to produce 1T-transition metal dichalcogenide few-layer nano sheets and/or monolayer nanosheets. An electrochemical capacitor comprising a composite electrode comprising 1T-MoS.sub.2 nanosheets and graphene, and a method of producing a composite electrode for use in an electrochemical capacitor.

The present invention provides a positive electrode active material for secondary battery and a secondary battery including the same. The positive electrode active material includes a core including a lithium composite metal oxide of Formula 1 below, a first surface-treated layer positioned on the surface of the core and including a lithium oxide of Formula 2 below, and a second surface treated layer positioned on the core or the first surface-treated layer and including a lithium compound of Formula 3. Thus, the present invention can improve capacity characteristics and output characteristics of a battery and also reduce the generation of gas,
Li.sub.aNi.sub.1-x-yCo.sub.xM1.sub.yM3.sub.zM2.sub.wO.sub.2 [Formula 1]
Li.sub.mM4O.sub.(m+n)/2 [Formula 2]
Li.sub.pM5.sub.qA.sub.r [Formula 3] (in formulae 1 to 3, A, M1 to M5, a, x, y, z, w, m, n, p, and q are the same as those defined in the specification).

According to one embodiment, an active material is provided. The active material includes particles of a monoclinic niobium titanium composite oxide. The particles include primary particles. The primary particles have an average aspect ratio of 5 or more.

A coated substrate is provided that comprises: a substrate; and a barrier coating comprising a compound having the formula: Ln.sub.2ABO.sub.s, where Ln comprises scandium, yttrium, lanthanum, cerium, praseodymium, neodymium, promethium, samarium, europium, gadolinium, terbium, dysprosium, holmium, erbium, thulium, ytterbium, lutetium, or mixtures thereof; A comprises Si, Ti, Ge, Sn, Ce, Hf, Zr, or a combination thereof; and B comprises Mo, W, or a combination thereof. In one embodiment, B comprises Mo.

According to one embodiment, provided is an active material including a composite oxide having a tetragonal crystal structure. The composite oxide is represented by general formula Li.sub.aTi.sub.bNb.sub.2?2dM.sub.c+2dO.sub.2b+5+3c. Here, M is one selected from the group consisting of W and Mo, 0?a?b+4+3c, 0<b<2?2d, and 0<c<2?4d.

Multimetal oxide composition comprising Mo, Bi, Fe, Cu and one or more than one of the elements Co and Ni and use thereof.