Interdiffusion of PCBM and P3HT Reveals Miscibility in a Photovoltaically Active Blend

Neil D. Treat, Michael A. Brady, Gordon Smith, Michael F. Toney, Edward J. Kramer, Craig J. Hawker and Michael L. Chabinyc
Advanced Energy Materials
1, 82-89

Polymer/fullerene blends: Bilayers of poly(3-hexyl thiophene) (P3HT) and [6,6]-phenyl-C61-butyric-acid-methyl-ester (PCBM) were fabricated to investigate the miscibility and mobility of the two components during thermal annealing. It is found that aggregates and/or molecular species of PCBM are miscible and mobile in disordered P3HT without disrupting the P3HT crystallite orientation or size.