A method of manufacturing a gas sensor for detecting xylene is provided. A method of manufacturing a gas sensor includes reacting a mixed material including a first material containing a cobalt (Co) element and a second material containing a chromium (Cr) element to form a CoCr.sub.2O.sub.4 hollow structure having a hollow shape.

The present invention relates to a positive electrode active material which has the structural stability of a lithium composite oxide constituting a positive electrode active material and a lithium secondary battery including the same. The lithium composite oxide constituting the positive electrode active material according to the present invention is able to reduce the surface area and grain boundary of secondary particles having a side reaction with an electrolyte solution, thereby improving high-temperature stability and reducing gas generation caused by the positive electrode active material, and the structural stability of the lithium composite oxide may be improved using a cation-mixing layer covering the surface of a primary particle.

Proposed are a layered Group III-V compound having ferroelectric properties, a Group III-V compound nanosheet that may be prepared using the same, and an electrical device including the materials. Proposed is a layered compound represented by [Formula 1] M.sub.x−mA.sub.yB.sub.z (M is at least one of Group I or Group II elements, A is at least one of Group III elements, B is at least one of Group V 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), and having ferroelectric-like properties.

Provided are methods for synthesizing a graphene gel. In embodiments, such a method comprises flowing a graphene oxide composition comprising graphene oxide and a solvent, the solvent having a boiling point higher than pure water, through a reaction chamber under conditions to deoxygenate the graphene oxide and induce gelation to form a graphene gel suspended in the solvent and flowing through the reaction chamber.

The invention utilizes swelling and fusion effects of graphene oxide in a solvent to implement cross-linked bonding of a graphene material itself and materials such as polymers, metal, paper, glass, carbon materials, and ceramics. The present invention not only overcomes the shortcoming in traditional adhesives of residual formaldehyde, but also has short drying time, high bonding strength and high corrosion resistance. The present invention is widely applied in the fields of aviation, aerospace, automobiles, machinery, construction, chemical, light industry, electronics, electrical appliances, and daily life, etc.

The present disclosure relates to an anode active material for a lithium secondary battery, a method of manufacturing the anode active material, and a lithium secondary battery including the anode active material. The anode active material includes natural graphite particles configured such that flaky natural graphite fragment particles having uneven (□□) surface defects are structured in a cabbage shape or at random and granulated, the surface and the inside of the natural graphite particles including a gap formed between the flaky natural graphite fragment particles, and a coating layer including amorphous or semicrystalline carbon formed on the surface of the flaky natural graphite fragment particles that form the gap and the surface of the natural graphite particles.

The present invention relates to a method for preparing ZSM-5 zeolite. The present invention can provide a method for preparing ZSM-5 zeolite comprising the steps of: preparing a first solution in a solution state by heating a mixture comprising a silica source, an alumina source, a neutralizing agent and a crystalline ZSM-5 nucleus; preparing a reaction mother liquid by mixing a second solution comprising salts into the first solution; and continuously crystallizing by continuously supplying the reaction mother liquid to a hydrothermal synthesis reactor, wherein formula [1] below is satisfied.
0.20≤W.sub.a/W.sub.b≤0.40  Formula [1]

Provided is a method for producing magnesium hydride, the method including a plasma treatment step of exposing a raw material mixture of at least one magnesium-based raw material selected from the group consisting of magnesium, magnesium hydroxide, and magnesium oxide and magnesium hydride to hydrogen plasma.

A CoVO.sub.x composite electrode and method of making is described. The composite electrode comprises a substrate with an average 0.5-5 μm thick layer of CoVO.sub.x having pores with average diameters of 2-200 nm. The method of making the composite electrode involves contacting the substrate with an aerosol comprising a solvent, a cobalt complex, and a vanadium complex. The CoVO.sub.x composite electrode is capable of being used in an electrochemical cell for water oxidation.

Disclosed are methods for preparing high-purity boehmite and porous gamma-alumina nano-powder, comprising: adding aluminum isopropoxide into water and stirring the aluminum isopropoxide added water, then adding aluminum hydroxide generated by hydrolysis of high-purity aluminum powder into that stirred water, stirring that aluminum hydroxide added water to obtain a mixed system; carrying out hydrothermal reaction on the mixed system, performing centrifuging, washing, drying and crushing to the reacted mixed system, obtaining high-purity boehmite; calcining the high-purity boehmite to obtain porous gamma (γ)-alumina nano-powder. By strictly controlling the addition of isopropanolic aluminum and the temperature as well as the duration of the hydrothermal reaction, the product boehmite γ-AlOOH obtains good character in terms of crystalline structure, purity, morphology and dispersion; γ-Al.sub.2O.sub.3 obtained after calcining remains basically the same morphology as that of boehmite powder with good powder dispersion and no major changes.