Fig. 1. Characterization of ZnO NPs, ZnO NPs plus CPP, ZnO NPs plus VC, ZnO NPs plus CPP plus VC: (a) TEM image of ZnO NPs; (b) TEM image of ZnO NPs plus CPP; (c) TEM image of ZnO NPs plus VC; (d) TEM image of ZnO NPs plus CPP plus VC; (e) XRD patterns of ZnO NPs were recorded in the range of 5–85 of 2 angles. All diffraction peaks can be perfectly indexed to hexagonal wurtzite structure of ZnO (JCPDS card no. 36-1451); (f) The size distribution of ZnO NPs.