Abstract: In an aspect of the present disclosure, a catalyst includes an oxide containing 5 or more types of rare earth elements and 1 or more types of platinum group elements. The catalyst has a configuration entropy of a cation site determined based on (i) the number of types of the rare earth elements and the platinum group element that can be arranged in the cation site in a crystalline structure of the oxide, and (ii) each proportion of the rare earth elements and the platinum group element of more than 1.7R, where R is a gas constant.

Abstract: A porous coordination polymer-ionic liquid composite according to the present invention includes an insulating structure composed of a porous coordination polymer, and an ionic liquid retained inside pores of the porous coordination polymer. The porous coordination polymer preferably has a main chain containing a typical metal element.

Abstract: A porous coordination polymer-ionic liquid composite according to the present invention includes an insulating structure composed of a porous coordination polymer, and an ionic liquid retained inside pores of the porous coordination polymer. The porous coordination polymer preferably has a main chain containing a typical metal element.

Abstract: A thermoelectric element, which has higher thermoelectric properties and shows an enlarged temperature difference between the both ends thereof is provided. A thermoelectric module having such thermoelectric element is also provided. The thermoelectric element having a pillar shape and having one end face and the other end face comprises; a first region containing a central axis; and a second region located at outside of the first region and having a protrusion which protrudes toward the central axis, wherein the first region has a thermal conductivity different from that of the second region.