Patent ID: 8512672

Claim:
A method for preparing zinc oxide (ZnO) nanoparticles, comprising: heating deionized water; dissolving zinc (Zn) salt in the deionized water to prepare a precursor solution; adding alkali salt in a solid state to the precursor solution to prepare a dispersion of ZnO nanoparticles; and separating the ZnO nanoparticles by solid-liquid separation and washing them with deionized water; and wherein each of said heating, dissolving and adding is performed at 95 to 100° C., and the alkali salt is a pellet satisfying Inequality (1), and said adding the alkali salt is performed by adding a plurality of the pellets at once so that the pH of the dispersion of ZnO nanoparticles is 7 to 8: 0.002 ×V sol ≦V pell ≦0.004 ×V sol (1) wherein V sol is the volume of the deionized water in said heating, and V pell is the volume of the pellet.