Electronic properties and morphology of Cu-Phthalocyanine - C${}_{60}$ composite mixtures

Abstract

Phthalocyanines in combination with C${}_{60}$ are benchmark materials for organic solar cells. Here we have studied the morphology and electronic properties of co-deposited mixtures (blends) of these materials forming a bulk heterojunction as a function of the concentration of the two constituents. For a concentration of 1:1 of CuPc:C${}_{60}$ a phase separation into about 100 nm size domains is observed, which results in electronic properties similar to layered systems. For low C${}_{60}$ concentrations (10:1 CuPc:C${}_{60}$) the morphology, as indicated by Low-Energy Electron Microscopy (LEEM) images, suggests a growth mode characterized by (amorphous) domains of CuPC, whereby the domain boundaries are decorated with C${}_{60}$. Despite of these markedly different growth modes, the electronic properties of the heterojunction films are essentially unchanged.

References in corpus (1)

• Understanding the Interface Dipole of Copper Phthalocyanine (CuPc)/C60: Theory and Experiment

Cited by in corpus (4)

• Direct observation of charge separation in an organic light harvesting system by femtosecond time-resolved XPS
• Site-specific probing of charge transfer dynamics in organic photovoltaics
• Electronic properties of Mn-Phthalocyanine - C${}_{60}$ bulk heterojunctions: combining photoemission and electron energy-loss spectroscopy
• Low-energy electron microscopy as a tool for analysis of self-assembled molecular layers on surfaces