Electrochromic structure and preparation method therefor

A method for preparing an electrochromic nanostructure, the method comprising:

• preparing a metal organic framework having a predetermined size;
• preparing a rectangular cuboid nanostructure for an electrochromic layer, the rectangular cuboid nanostructure having a structure comprising nanopores by heat-treating the metal organic framework having the predetermined size;
• and
• attaching electrochromic materials to surfaces of the rectangular cuboid nanostructure by immersing the rectangular cuboid nanostructure in one or more solutions including one or more of the electrochromic materials,
• wherein the preparing the rectangular cuboid nanostructure comprises:
• mixing metal organic frameworks having different sizes at a predetermined ratio;
• and
• preparing pores in the rectangular cuboid nanostructure having different sizes by heat-treating the metal organic frameworks mixed at the predetermined ratio, wherein the rectangular cuboid nanostructure includes:
• a first layer having first pores of a first size, and a first electrochromic material of a first color attached to the first pores;
• a second layer having second pores of a second size smaller than the first size, and a second electrochromic material of a second color different from the first color and attached to the second pores;
• and
• a third layer having third pores of a third size smaller than the second size, and a third electrochromic material of a third color different from the first and second colors and attached to the third pores,
• wherein an upper surface of the second layer directly contacts a lower surface of the first layer, and a lower surface of the second layer directly contacts an upper surface of the third layer,
• wherein side surfaces of the first, second and third layers form one side surface of the rectangular cuboid nanostructure, and the one side surface of the rectangular cuboid nanostructure includes the first, second and third pores, and
• wherein the first electrochromic material has a larger diameter than the second electrochromic material.

An electrochromic device comprising:

• a first transparent electrode and a second transparent electrode;
• an ion storage layer;
• an electrochromic layer;
• and
• an electrolyte layer disposed between the ion storage layer and the electrochromic layer,
• wherein the electrochromic layer includes a rectangular cuboid nanostructure having a structure comprising nanopores, and electrochromic materials attached to surfaces of the rectangular cuboid nanostructure,
• wherein the rectangular cuboid nanostructure includes:
• a first layer having first pores of a first size, and a first electrochromic material of a first color attached to the first pores;
• a second layer having second pores of a second size smaller than the first size, and a second electrochromic material of a second color different from the first color and attached to the second pores;
• and
• a third layer having third pores of a third size smaller than the second size, and a third electrochromic material of a third color different from the first and second colors and attached to the third pores,
• wherein an upper surface of the second layer directly contacts a lower surface of the first layer, and a lower surface of the second layer directly contacts an upper surface of the third layer,
• wherein side surfaces of the first, second and third layers form one side surface of the rectangular cuboid nanostructure, and the one side surface of the rectangular cuboid nanostructure includes the first, second and third pores, and
• wherein the first electrochromic material has a larger diameter than the second electrochromic material.