Abstract: What is provided is a layered double hydroxide crystal for achieving higher ion-exchange capacity than that of the related art. The layered double hydroxide crystal 1 according to the present embodiment is represented by Formula (1) and composed of a plurality of crystal grains 10 each of which has a lamination structure in which a plurality of plate-shaped crystals (11), (11), . . . are laminated, in which particle sizes of the plurality of crystal grains (10), (10), . . . are uniform on a microscale. [Ni2+1-xFe3+x(OH)2].[(Cl?)X/2]??(1) (Where, 0.25<x?0.

Abstract: A method and apparatus for producing core-shell type metal nanoparticles which are excellent in productivity are provided, in particular, the present invention provides a method of production of core-shell type metal nanoparticles including (a) a step of introducing a solution of a salt of a first metal to a first flow path of a flow type reaction apparatus and applying plasma to the solution of the salt of the first metal in the first flow path to obtain a solution which contains metal nanoparticles of the first metal and (b) a step of introducing a solution of a salt of a second metal to a second flow path of the flow type reaction apparatus, making it merge with the solution which contains metal nanoparticles of the first metal to obtain a mixed solution, and applying plasma to the mixed solution to cover the metal nanoparticles of the first metal by the second metal.

Abstract: A method of production of core/shell type nanoparticles includes the following steps: a first step of applying a first power to cause the generation of the plasma so as to selectively cause the precipitation of a first metal so as to form nanoparticles as cores and a second step of applying a second power which is larger than the first power to cause the generation of the plasma so as to cause the precipitation of a second metal which has a smaller oxidation reduction potential than the first metal on the core surface so as to form shells which are comprised of the second metal which cover the cores which are comprised of the first metal.

Abstract: A method and apparatus for producing core-shell type metal nanoparticles which are excellent in productivity are provided, in particular, the present invention provides a method of production of core-shell type metal nanoparticles including (a) a step of introducing a solution of a salt of a first metal to a first flow path of a flow type reaction apparatus and applying plasma to the solution of the salt of the first metal in the first flow path to obtain a solution which contains metal nanoparticles of the first metal and (b) a step of introducing a solution of a salt of a second metal to a second flow path of the flow type reaction apparatus, making it merge with the solution which contains metal nanoparticles of the first metal to obtain a mixed solution, and applying plasma to the mixed solution to cover the metal nanoparticles of the first metal by the second metal.

Abstract: A method of production of core/shell type nanoparticles includes the following steps: a first step of applying a first power to cause the generation of the plasma so as to selectively cause the precipitation of a first metal so as to form nanoparticles as cores and a second step of applying a second power which is larger than the first power to cause the generation of the plasma so as to cause the precipitation of a second metal which has a smaller oxidation reduction potential than the first metal on the core surface so as to form shells which are comprised of the second metal which cover the cores which are comprised of the first metal.