Femtosecond excited state dynamics of liquid deposited magnesium phthalocyanine thin films.

• Phthalocyanines are one of the most widely studied organic semiconductor materials for decades. • A low-cost liquid deposition method is introduced to prepare phthalocyanine films. • The Q band of phthalocyanine films redshifted in the solid-state film compare to that in solution. • The aggregation caused by close packing in the solid film state had small influence on the decay of singlet excited state. Phthalocyanines (Pcs) are one of the most widely studied organic semiconductor materials, and many film fabrication methods have been developed and used in the Pcs film fabrication. Here, we introduced a low-cost liquid deposition method to prepare magnesium phthalocyanine (MgPc) film and characterized it using AFM, XRD, UV–vis absorption spectroscopy and femtosecond transient absorption spectroscopy. We found that the Q band of MgPc red-shifted in the solid-state film and the aggregation in the solid film state has a little influence on the decay of singlet excited state, but have a more significant impact on the non-radiative relaxation of the triplet state. [ABSTRACT FROM AUTHOR]