ZnO nanorods were synthesized similar to our previous work with a little modification [11].
In a typical procedure, Zn(NO3)2·6H2O (Reagent Grade, 98% Sigma-Aldrich) was dissolved in 100 ml of deionized water to make 0.1 M solution.
Ammonia water was added to this solution to make pH 7, followed by vigorous stirring for 1 h.