Solvent induced aggregation of protoporphyrin and octacarboxylphthalocyanine of zinc deposited on gold surface

► ZnPP & ZnPc(COOH)8 are highly soluble in DMF, and ZnPc(COOH)8 partly in ethanol. ► ZnPP & ZnPc(COOH)8 clustering in solution is increased along with ethanol content. ► Nanograin size in macrocycle films is controlled by clustering in solution. ► Aggregation is enhanced for ZnPc(COOH)8 compared to ZnPP in both solution and films. ► Thin films of ZnPc(COOH)8 grains exhibit Q absorption band splitting.