Please clarify you question. What kind of stability you are looking for, is it phase or structural stability or what?. Also mention whether you are employing CBD/hydrothermal synthesis for you ZnO nano powder.
@Avishek.... I have used n-ZnO as an adsorbent. I have opted co-precipitation method. I want to know about structural and phase stability of n-ZnO in acidic and alkaline medium. Also suggest any reference supporting the same.