Simple, material-efficient microgranulation methods are disclosed for aggregating precursor particles into larger product particles with improved properties and, in some instances, novel structures. The product particles are useful in applications requiring uniform, smooth, spherical, or rounded particles such as for electrode materials in lithium batteries and other applications.

Various embodiments may include a battery electrode, comprising: an iron electrode body comprising iron active material and a zinc sulfide additive, wherein the zinc sulfide additive comprises crystalline cubic zinc sulfide. Various embodiments may include a battery electrode, comprising: an iron electrode body comprising iron active material and a manganese sulfide additive, wherein the manganese sulfide additive comprises crystalline cubic manganese sulfide. Various embodiments may include an iron electrode battery, comprising: an iron electrode; and a sulfide reservoir separate from the iron electrode, the sulfide reservoir comprising crystalline cubic zinc sulfide. Various embodiments may include an iron electrode battery, comprising: an iron electrode and a sulfide reservoir separate from the iron electrode, the sulfide reservoir comprising crystalline cubic manganese sulfide.

This disclosure provides systems, methods, and apparatus related to lithium metal oxyfluorides. In one aspect, a method for manufacturing a lithium metal oxyfluoride having a general formula Li.sub.1+x(MM′).sub.zO.sub.2-yF.sub.y, with 0.6≤z≤0.95, 0<y≤0.67, and 0.05≤x≤0.4, the lithium metal oxyfluoride having a cation-disordered rocksalt structure, includes: providing at least one lithium-based precursor; providing at least one redox-active transition metal-based precursor; providing at least one redox-inactive transition metal-based precursor; providing at least one fluorine-based precursor comprising a fluoropolymer; and mixing the at least one lithium-based precursor, the at least one redox-active transition metal-based precursor, the at least redox-inactive transition metal-based precursor, and the at least one fluorine-based precursor comprising a fluoropolymer to form a mixture.

An object is to reduce variation in shape of crystals that are to be formed. Solutions containing respective raw materials are made in an environment where an oxygen concentration is lower than that in air, the solutions containing the respective raw materials are mixed in an environment where an oxygen concentration is lower than that in air to form a mixture solution, and with use of the mixture solution, a composite oxide is formed by a hydrothermal method.

Herein disclosed are compositions for passive NOx adsorption and oxidation that include at least a manganese-based oxide and one or more promoter materials and methods for making and using said compositions. The promotor materials may include a rare earth, transition, or main group metal. The compositions may be used in NOx emission control system and adsorbs NOx compounds at low temperatures and then release NOx at higher temperatures, where the NOx can be oxidized, without the hybridized MnOX composition breaking down. The compositions are capable of maintaining a sufficiently large surface area at high temperatures found in the emissions gas streams of internal combustion engines necessary for the complete elimination of NOx.

A nanoparticle for radiation protection is provided. The nanoparticle for radiation protection comprises a first metal oxide nanoparticle. The nanoparticle for radiation protection may further comprise a second metal oxide layer formed on a surface of the first metal oxide nanoparticle. The nanoparticle for radiation protection may have a polar interface between the first metal oxide nanoparticle and the second metal oxide layer.

In a method for the precipitation of particles of a metal carbonate material comprising nickel and manganese in an atomic ratio of 0≤Ni:Mn≤1:3, aqueous solutions comprising sulfates or nitrates of nickel and manganese are mixed with aqueous solutions of carbonates or mixtures of carbonates and hydroxides of sodium or potassium in a stirred reactor at pH>7.5 without the use of a chelating agent. Thereby agglomerated particles are formed without any subsequent process steps, in particular no subsequent process at temperatures higher than the precipitation temperature.

In relation to a Cu-based delafossite-type oxide that is effective as an exhaust gas purification catalyst, Cu is placed in a high catalytic activity low-valence state, whereby a novel Cu-based delafossite-type oxide having higher activity than in the past is provided. Proposed is a delafossite-type oxide for an exhaust gas purification catalyst that is represented by a general formula ABO.sub.2, wherein Cu and Ag are contained in the A site of the general formula, one or two or more elements selected from the group consisting of Mn, Al, Cr, Ga, Fe, Co, Ni, In, La, Nd, Sm, Eu, Y, V, and Ti are contained in the B site of the general formula, and Ag is contained at a ratio of 0.001 at. % or more and less than 20 at. % in the A site of the general formula.

A positive-electrode active material contains a compound represented by the following composition formula (1):
Li.sub.xMe.sub.yA.sub.zO.sub.αF.sub.β  (1) where Me denotes one or more elements selected from the group consisting of Mn, Co, Ni, Fe, Al, Cu, Nb, Mo, Ti, Cr, Zr, Zn, Na, K, Ca, Mg, Pt, Au, Ru, and W, A denotes one or more elements selected from the group consisting of B, Si, and P, and the following conditions: 1.3≤x≤2.1, 0.8≤y≤1.3, 0<z≤0.2, 1.8≤α≤2.9, and 0.1≤β≤1.2 are satisfied. A crystal structure of the compound belongs to a space group Fm-3m.

As an aspect of an embodiment, a crystal contains a metal oxide containing Ga and Mn and having a corundum structure.