Nano-structured Langmuir-Blodgett mixed films of titanyl(IV) phthalocyanine and bis(neopentylimido)perylene

Langmuir and Langmuir-Blodgett (LB) films of mixed titanyl(IV) phthalocyanine (TiOPc)-bis (neopentylimido)perylene (BNPTCD) were fabricated and characterized. The surface pressure-area isotherms (π-A) of the mixed Langmuir films were recorded and revealed an unusual expansion of the surface area per molecule. The expansion is attributed to the interpenetration of the BNPTCD in the space available between adjacent Pc macrocycles preventing molecular stacking and forcing the expansion. This effect is a result of the high degree of mixing between species in the floating monolayer. This assumption was further supported by means of surface enhanced Raman scattering (SERS) mapping technique that proved the absence of large segregated domains in the LB film, in other words, the absence of phase separated regions, in agreement with a unique degree of miscibility.