Provided is a method of producing fine particulate barium calcium titanate in which calcium forms a homogeneous solid solution. The present invention relates to a method of producing a perovskite compound represented by the following formula (1):

Ba.sub.(1-x)A.sub.xTiO.sub.3  (1)

wherein A represents Ca or Sr, and x is a number satisfying 0.00<x≤0.30,

the method including: a first step of acid washing barium titanate to provide barium titanate having a ratio of barium element to titanium element of lower than 1.00; a second step of mixing the barium titanate obtained in the first step and a calcium salt or a strontium salt and drying the mixture to provide a dry mixture; and a third step of heating the dry mixture obtained in the second step.

Disclosed is a method for synthesizing two-dimensional (2D) silicon carbide and other materials. The method includes the use of hexagonal SiC precursor in a wet exfoliation technique. The method may also include synthesizing two-dimensional (2D) silicon carbide by a chemical vapor deposition method, or a combination of a liquid exfoliation technique and a chemical vapor deposition method.

A process for gas-phase synthesis of titanium dioxide aerosol gels with controlled monomer size and crystalline phase using a diffusion flame aerosol reactor operated in a buoyancy-opposed configuration is disclosed. The process includes introducing a precursor stream into a diffusion flame aerosol reactor, introducing a fuel stream into the reactor, combusting the precursor stream and the fuel stream in a flame to form at least one nanoparticle, and operating the reactor in a down-fired buoyancy-opposed configuration to produce the aerosol gel.

Provided are a sodium ion-conductive crystal-containing solid electrolyte sheet capable of giving excellent battery characteristics even when reduced in thickness, and an all-solid-state battery using the same. The solid electrolyte sheet contains at least one type of sodium ion-conductive crystal selected from β″-alumina and NASICON crystal and has a thickness of 500 μm or less and a flatness of 200 μm or less.

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.

A positive electrode active material has a small difference in a crystal structure between the charged state and the discharged state. For example, the crystal structure and volume of the positive electrode active material, which has a layered rock-salt crystal structure in the discharged state and a pseudo-spinel crystal structure in the charged state at a high voltage of approximately 4.6 V, are less likely to be changed by charging and discharging as compared with those of a known positive electrode active material. In order to form the positive electrode active material having the pseudo-spinel crystal structure in the charged state, it is preferable that a halogen source such as a fluorine and a magnesium source be mixed with particles of a composite oxide containing lithium, a transition metal, and oxygen, which is synthesized in advance, and then the mixture be heated at an appropriate temperature for an appropriate time.

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.

The present disclosure discloses a W-containing high-nickel ternary cathode material, including both spherical secondary particles and single-crystal particles. There is basically no W inside the single-crystal particles, and the spherical secondary particles are doped with W. A preparation method of the W-containing high-nickel ternary cathode material includes: mixing a nickel salt, a cobalt salt, and a manganese salt according to a specified molar ratio, and adding an ammonia solution and a sodium hydroxide solution for co-precipitation to prepare a precursor A; mixing a nickel salt, a cobalt salt, a manganese salt, and a tungsten salt, and adding an ammonia solution and a sodium hydroxide solution for co-precipitation to prepare a W-containing precursor B; and mixing the precursor A, the precursor B, a lithium source, and a doping element M-containing compound, and subjecting a resulting mixture to high-temperature sintering in an oxygen atmosphere to obtain the high-nickel ternary cathode material including both spherical secondary particles and single-crystal particles. While increasing the capacity, the spherical secondary particles in the product of the present disclosure can ensure that a crystal structure will not undergo obvious phase transition when lithium ions are deintercalated during a cycling process, which helps to improve the cycling performance.

This invention relates to a process for treating acid mine drainage (AMD). The process includes the steps of adjusting the pH of the AMD to be in the range of 3 to 5; adding maghemite nanoparticles to form a slurry; and a) aerating the slurry obtained in step 3), or b) simultaneously heating and mixing the slurry obtained in step 3). Thereafter maghemite nanoparticles loaded with one or more metals and sulphate and precipitated metals is separated from the slurry.

Slug flow manufacturing systems and methods for production of battery microparticle materials such as nickel-cobalt-manganese oxide (NCM) are disclosed. The slug flow reactor system is capable of producing microparticles reproducibly and continuously in desired scales. The system may be run with fast kinetics (e.g., complete reaction from nucleation to particle recovery completes within a few minutes) and near-ambient reaction temperature (e.g., allowing to use inexpensive plastic tubing). The system allows control of composition (overall, and radial profile) and size of microparticles without changing chemistry nor increasing temperature. The platforms offers the ability to conveniently generate uniform microparticles, of controllable size with an ease of scale up.