A multi-channel direct-deposit assembly method is disclosed to high-throughput synthesize three-dimensional macroporous/mesoporous (3DMM) material array with precisely controlled composition, pore size, and pore structure. The macropore size of the synthesized 3DMM material is in the range of 50-1000 nm; the mesopore size of the synthesized 3DMM material is in the range of 1-50 nm. The surface area of the 3DMM material is in the range of 20-1000 m.sup.2/g. The 3DMM material array can be used for rapid synthesis, screening and manufacture of catalysts and nanosensors.

A process is disclosed for the oxidation and thermal decomposition of metal chlorides, leading to an efficient and effective separation of nuisance elements such as iron and aluminum from value metals such as copper and nickel. In the first instance, oxidation, especially for iron, is effected in an electrolytic reactor, wherein ferrous iron is oxidised to ferric. In a second embodiment, the oxidised solution is treated in a hydrothermal decomposer reactor, wherein decomposable trivalent metal chlorides form oxides and divalent metal chlorides form basic chlorides. The latter are soluble in dilute hydrochloric acid, and may be selectively re-dissolved from the hydrothermal solids, thereby effecting a clean separation. Hydrochloric acid is recovered from the hydrothermal reactor.

Provided are a method of preparing a metal oxide-silica composite aerogel, which includes preparing metal oxide-silica composite precipitates by adding a metal salt solution to a silicate solution and performing a reaction, and drying the metal oxide-silica composite precipitates by irradiation with infrared rays in a wavelength range of 2 m to 8 m, and a metal oxide-silica composite aerogel having excellent physical properties, such as low tap density and high specific surface area, as well as excellent pore properties prepared by the method.

Composite oxide fine particles are produced by sol-gel method under conditions in which coarse particles and aggregated particles are unlikely to be generated, and the composite oxide fine particles are further wet-filtered using a filter to remove the coarse particles and the aggregated particles. Then, a salt is added to a dispersion of the composite oxide fine particles to produce weak aggregates of the composite oxide fine particles in the dispersion. A solid content is separated from the dispersion of the composite oxide fine particles containing the aggregates, and then dried. The solid content is easily made finer because no firm aggregates are generated during the drying. That is, composite oxide fine particles containing no coarse particles and aggregated particles are obtained. Use of a known cracking means can further reduce the amount of coarse particles.

A multi-channel direct-deposit assembly method is disclosed to high-throughput synthesize three-dimensional macroporous/mesoporous (3DMM) material array with precisely controlled composition, pore size, and pore structure. The macropore size of the synthesized 3DMM material is in the range of 50-1000 nm; the mesopore size of the synthesized 3DMM material is in the range of 1-50 nm. The surface area of the 3DMM material is in the range of 20-1000 m.sup.2/g. The 3DMM material array can be used for rapid synthesis, screening and manufacture of catalysts and nanosensors.

The present disclosure provides methods for producing cathode materials for lithium ion batteries. Cathode materials that contain manganese are emphasized. Representative materials include Li.sub.xNi.sub.1-y-zMn.sub.yCo.sub.zO.sub.2 (NMC) (where x is in the range from 0.80 to 1.3, y is in the range from 0.01 to 0.5, and z is in the range from 0.01 to 0.5), Li.sub.xMn.sub.2O.sub.4(LM), and Li.sub.xNi.sub.1-yMn.sub.yO.sub.2 (LMN) (where x is in the range from 0.8 to 1.3 and y is in the range from 0.0 to 0.8). The process includes reactions of carboxylate precursors of nickel, manganese, and/or cobalt and lithiation with a lithium precursor. The carboxylate precursors are made from reactions of pure metals or metal compounds with carboxylic acids. The manganese precursor contains bivalent manganese and the process controls the oxidation state of manganese to avoid formation of higher oxidation states of manganese.

A method of producing ceria nanocrystals is provided. The method includes providing a gas that includes ozone to a solution that includes a cerium salt, and obtaining ceria nanocrystals from the solution after the gas is provided to the first solution. A method of producing nanoparticles is provided. The method includes providing a gas that includes ozone to a solution that includes a metal salt that includes at least one of a transition metal or a lanthanide, and producing at least one of metal oxide nanoparticles, metal oxynitrate nanoparticles, or metal oxyhydroxide nanoparticles from the solution after the gas is provided to the solution.

A method of preparing a catalyst for oxidative dehydrogenation that includes coprecipitation and injecting inert gas or air at a specific time point to reduce the ratio of an inactive -Fe.sub.2O.sub.3 crystal structure, thereby improving the activity of the catalyst. Also provided is a method of performing oxidative dehydrogenation using the catalyst. When oxidative dehydrogenation of butene is performed using the catalyst, side reaction may be reduced, and selectivity for butadiene may be improved, providing butadiene with high productivity.

A composition including cerium and zirconium oxides, including at least 30 wt.-% cerium oxide is desired. Following calcination at a temperature of 900 DEG C. for 4 hours, the composition has two populations of pores, the diameters of the first population being centered around a value of between 5 nm and 15 nm for a composition including 30% to 65% cerium oxide or between 10 nm and 20 nm for more than 65% cerium oxide and the diameter of the second population being centered around a value of between 45 nm and 65 nm for 30% to 65% cerium oxide or between 60 nm and 100 nm for more than 65% cerium oxide.

A ceramic material, a varistor and methods for forming a ceramic material and a varistor are disclosed. In an embodiment, a ceramic material includes ZnO as a main component and additives selected from the group consisting of an Al.sup.3+-containing solution, a Ba.sup.2+-containing solution, and at least one compound containing a metal element, wherein the metal element is selected from the group consisting of Bi, Sb, Co, Mn, Ni, Y, and Cr.