• Puttisong, Yuttapoom
• Chen, Weimin M.
• Moro, Fabrizio
• Wang, Gang
• Berggren, Magnus
• Yan, Hongping
• Hultmark, Sandra
• Müller, Christian
• Wang, Suhao
• Riera-Galindo, Sergi
• Ruoko, Tero-Petri
• Fabiano, Simone

Abstract

<p>Doping of organic semiconductors is a powerful tool to optimize the performance of various organic (opto)electronic and bioelectronic devices. Despite recent advances, the low thermal stability of the electronic properties of doped polymers still represents a significant obstacle to implementing these materials into practical applications. Hence, the development of conducting doped polymers with excellent long-term stability at elevated temperatures is highly desirable. Here, we report on the sequential doping of the ladder-type polymer poly(benzimidazobenzophenanthroline) (BBL) with a benzimidazole-based dopant (i.e., N-DMBI). By combining electrical, UV-vis/infrared, X-ray diffraction, and electron paramagnetic resonance measurements, we quantitatively characterized the conductivity, Seebeck coefficient, spin density, and microstructure of the sequentially doped polymer films as a function of the thermal annealing temperature. Importantly, we observed that the electrical conductivity of N-DMBI-doped BBL remains unchanged even after 20 h of heating at 190 °C. This finding is remarkable and of particular interest for organic thermoelectrics.</p>

Topics

• density
• impedance spectroscopy
• microstructure
• polymer
• x-ray diffraction
• semiconductor
• annealing
• electrical conductivity