Material for storing and releasing oxygen

A material for storing and releasing oxygen, consisting of a reactive ceramic made of copper, manganese and iron oxides, produced by powder and solid state preparation from various copper, manganese and iron oxides forming different compounds with each other depending on the oxygen content bound in the material,

• wherein single oxides may be present next to one another, but also mixed oxides or combinations of both may be present at the same time,
• wherein the reactive ceramic has a chemical composition in which the molar ratio between the portion of copper and the combined portion of manganese and iron is between 0.7/0.3 and 0.4/0.6, and the molar ratio between manganese and iron is between 0.2/0.8 and 0.99/0.01,
• wherein the structures of crednerite (CuMn1−xFexO2 with 0≤x≤0.75) and delafossite (CuFe1−xMnxO2 with 0≤x<0.25), spinel (CuMn2(1−x)Fe2xO4 with 0≤x≤1), tenorite (CuO), hausmannite (Mn3O4) and cuprite (Cu2O) appear,
• wherein the relationship of the single phases to one another is based on the charge state of the ceramic material,
• wherein, subject to a oxygen partial pressure of a surrounding atmosphere of oxygen-containing gas mixtures, air, oxygen-poor or oxygen-free gases or vacuum and/or an ambient temperature, the reactive ceramic has a transition region that can be passed through any number of times, said transition region being between a discharge threshold state of a three-phase crednerite/cuprite/hausmannite mixed ceramic and a charge threshold state of a two-phase spinel/tenorite mixed ceramic,
• wherein in the discharge threshold state due to an increased portion of manganese delafossite is transformed into a crystallographically distorted crednerite wherein a higher oxygen storage capacity of the reactive ceramic is achieved,
• wherein a passing through the transition region from the discharge threshold state towards the charge threshold state is associated with oxygen uptake and a passing through the transition region from the charge threshold state towards the discharge threshold state is associated with oxygen release,
• wherein the phase content of the reactive mixed ceramic depends on the charge state of the oxygen storage material,
• wherein the reaction direction and the reaction progress are influenced by the combination of the variables of the oxygen partial pressure of the surrounding atmosphere and the temperature of the material,
• wherein the reaction times for charging and discharging the reactive ceramic are in the range of a few seconds to minutes, and
• wherein the reactive ceramic has self-porosification due to the oxygen emission during passing through the transition region towards the discharge threshold state, wherein a porosity in the range of 25% by volume to 50% by volume occurs in the reactive ceramic.