METHODS OF MANUFACTURING NANOCRYSTAL THIN FILMS AND ELECTROCHROMIC DEVICES CONTAINING NANOCRYSTAL THIN FILMS
A method of forming a nanocrystal thin film (NTF) and an electrochromic (EC) device including the NTF, the method including depositing a precursor solution on a substrate to form a precursor layer, and annealing the precursor layer to form the NTF on the substrate. The precursor solution includes metal oxide nanoparticles, a solvent, and C8 or lower capping ligands bound to the metal oxide nanoparticles.
1 . An electrochromic (EC) device comprising:
a first substrate;
a second substrate;
a transparent first conductor disposed between the first and the second substrates;
a transparent second conductor disposed between the first and the second substrates;
a working electrode disposed between the first and the second conductors;
a counter electrode disposed between the working electrode and the second conductor, the counter electrode comprising nickel oxide nanoparticles having an average particle size ranging from about 1 nm to less than 5 nm; and
an electrolyte disposed between the working electrode and the counter electrode.
2 . The EC device of claim 1 , wherein the nickel oxide nanoparticles comprise NiO x , where 1≤x≤1.5.
3 . The EC device of claim 2 , wherein the nickel oxide nanoparticles comprise NiO.
4 . The EC device of claim 1 , wherein the nickel oxide nanoparticles have an average particle size ranging from about 2 nm to about 3 nm.
5 . The EC device of claim 1 , wherein the nickel oxide nanoparticles comprise complementary nanoparticles.
6 . The EC device of claim 5 , wherein the counter electrode further comprises passive nanoparticles comprising CeO 2 , CeVO 4 , TiO 2 , indium tin oxide (ITO), In 2 O 3 (Indium(III) oxide), SnO 2 (tin(IV) dioxide), manganese or antimony doped tin oxide, aluminum doped zinc oxide, ZnO (zinc oxide), gallium zinc oxide, indium gallium zinc oxide (IGZO), molybdenum doped indium oxide, Fe 2 O 3 , V 2 O 5 , or mixtures thereof.
7 . The EC device of claim 6 , wherein the counter electrode comprises:
a complementary layer comprising the complementary nanoparticles and the passive nanoparticles disposed in a metal oxide matrix; and
a passive layer disposed between the complementary layer and the electrolyte.
8 . The EC device of claim 7 , wherein the matrix comprises LiNbO 3 (lithium niobate), Li 2 WO 4 (lithium tungstate), LiTaO 3 (lithium tantalite), or mixtures thereof.
9 . The EC device of claim 7 , wherein the passive layer comprises passive nanoparticles disposed in a flux material.
10 . The EC device of claim 1 , wherein at least one the counter electrode, the working electrode, the first transparent conductor, the second transparent conductor, or the electrolyte comprises a structural component configured to at least one of reduce shrinkage during annealing or support nanoparticles during annealing of the EC device.
11 . The EC device of claim 11 , wherein the structural component comprises a scaffolding agent, oversized nanoparticles, a matrix, or any combination thereof.