Provided is a fluoride phosphor including a fluoride particle and a fluorine compound containing zirconium and disposed on at least a portion of the surface of the fluoride particle. The fluoride particle has a composition including an element M including at least one selected from the group consisting of Group 4 elements, Group 13 elements, and Group 14 elements; at least one selected from the group consisting of an alkali metal and an ammonium ion; manganese; and fluorine atoms. In the composition, when the total number of moles of the alkali metal and the ammonium ion is 2, the number of moles of the manganese is greater than 0 and less than 0.2, the total number of moles of the element M is greater than 0.8 and less than 1, and the number of moles of the fluorine atoms is greater than 5 and less than 7.

Provided is a fluoride phosphor including a fluoride particle and a fluorine compound containing zirconium and disposed on at least a portion of the surface of the fluoride particle. The fluoride particle has a composition including an element M including at least one selected from the group consisting of Group 4 elements, Group 13 elements, and Group 14 elements; at least one selected from the group consisting of an alkali metal and an ammonium ion; manganese; and fluorine atoms. In the composition, when the total number of moles of the alkali metal and the ammonium ion is 2, the number of moles of the manganese is greater than 0 and less than 0.2, the total number of moles of the element M is greater than 0.8 and less than 1, and the number of moles of the fluorine atoms is greater than 5 and less than 7.

Provided are a positive electrode active material including a lithium manganese-based oxyhalide represented by Formula 1 and having a disordered rock-salt structure:

Li.sub.0.5+aMn.sub.bM.sub.cO.sub.dX.sub.e[Formula 1] wherein, in Formula 1, M is at least one selected from the group consisting of titanium (Ti), nickel (Ni), zirconium (Zr), vanadium (V), cobalt (Co), tin (Sn), iron (Fe), iridium (Ir), chromium (Cr), lead (Pb), and ruthenium (Ru) and is preferably Ti, X is a halogen element and is preferably fluorine (F), and 0<a0.7, 0.5b<1, 0<cb/2, 1.5d1.9, 0.1e0.5, and d+e2.

Provided are a positive electrode active material including a lithium manganese-based oxyhalide represented by Formula 1 and having a disordered rock-salt structure:

Li.sub.0.5+aMn.sub.bM.sub.cO.sub.dX.sub.e[Formula 1] wherein, in Formula 1, M is at least one selected from the group consisting of titanium (Ti), nickel (Ni), zirconium (Zr), vanadium (V), cobalt (Co), tin (Sn), iron (Fe), iridium (Ir), chromium (Cr), lead (Pb), and ruthenium (Ru) and is preferably Ti, X is a halogen element and is preferably fluorine (F), and 0<a0.7, 0.5b<1, 0<cb/2, 1.5d1.9, 0.1e0.5, and d+e2.

A method of removing hydrogen sulfide from a subterranean geological formation includes injecting a drilling fluid suspension in the subterranean geological formation. The drilling fluid suspension has a pH of 10 or more and includes a layered triple hydroxide material, including manganese, copper, and aluminum, in an amount of 0.01 to 1.5 percent by weight of the drilling fluid suspension. The method further includes circulating the drilling fluid suspension in the subterranean geological formation and forming a water-based mud and scavenging the hydrogen sulfide from the subterranean geological formation by reacting the hydrogen sulfide with the layered triple hydroxide material in the water-based mud.

A method of removing hydrogen sulfide from a subterranean geological formation includes injecting a drilling fluid suspension in the subterranean geological formation. The drilling fluid suspension has a pH of 10 or more and includes a layered triple hydroxide material, including manganese, copper, and aluminum, in an amount of 0.01 to 1.5 percent by weight of the drilling fluid suspension. The method further includes circulating the drilling fluid suspension in the subterranean geological formation and forming a water-based mud and scavenging the hydrogen sulfide from the subterranean geological formation by reacting the hydrogen sulfide with the layered triple hydroxide material in the water-based mud.

The present invention belongs to the field of battery materials, and relates to a process for preparing a particulate lithium manganese nickel spinel compound, and materials produced by the process. The process of the invention uses Mn-containing precursors, Ni-containing precursors, Li-containing precursors and optionally M-containing precursor which form substantially no NOx gases during calcination. The particulate lithium manganese nickel spinel compound product of the process may find use in a lithium ion battery.

The present invention belongs to the field of battery materials, and relates to a process for preparing a particulate lithium manganese nickel spinel compound, and materials produced by the process. The process of the invention uses Mn-containing precursors, Ni-containing precursors, Li-containing precursors and optionally M-containing precursor which form substantially no NOx gases during calcination. The particulate lithium manganese nickel spinel compound product of the process may find use in a lithium ion battery.

The present invention discloses a preparation method for a spherical ZnMn metal compound. The preparation method comprises the following steps: adding a metal ion solution to a weak acid carbon dot solution; and then, adding a sodium carbonate solution to the above solution at an oil bath while stirring to obtain a spherical ZnMn metal carbonate compound. The present invention proposes that using water-soluble or ethanol-soluble carbon dots as a carrier and polyvinylpyrrolidone as a surfactant to prepare the spherical ZnMn metal compound, a novel preparation method for the ZnMn metal compound is formed. The prepared material may be applied to a lithium ion battery and may further be applied to application researches in the field of synthesis of other electrochemical energy sources or photocatalytic materials.

The present invention discloses a preparation method for a spherical ZnMn metal compound. The preparation method comprises the following steps: adding a metal ion solution to a weak acid carbon dot solution; and then, adding a sodium carbonate solution to the above solution at an oil bath while stirring to obtain a spherical ZnMn metal carbonate compound. The present invention proposes that using water-soluble or ethanol-soluble carbon dots as a carrier and polyvinylpyrrolidone as a surfactant to prepare the spherical ZnMn metal compound, a novel preparation method for the ZnMn metal compound is formed. The prepared material may be applied to a lithium ion battery and may further be applied to application researches in the field of synthesis of other electrochemical energy sources or photocatalytic materials.