Title Role of coherence and delocalization in photo-induced electron transfer at organic interfaces /
Authors Abramavičius, Vytautas ; Pranculis, Vytenis ; Melianas, Armantas ; Inganäs, O ; Gulbinas, Vidmantas ; Abramavičius, Darius
DOI 10.1038/srep32914
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Is Part of Scientific reports.. London : Nature Publishing Group. 2016, Vol. 6, Art. No. 32914.. ISSN 2045-2322
Keywords [eng] solar-cells ; charge separation ; generation ; energy ; states
Abstract [eng] Photo-induced charge transfer at molecular heterojunctions has gained particular interest due to the development of organic solar cells (OSC) based on blends of electron donating and accepting materials. While charge transfer between donor and acceptor molecules can be described by Marcus theory, additional carrier delocalization and coherent propagation might play the dominant role. Here, we describe ultrafast charge separation at the interface of a conjugated polymer and an aggregate of the fullerene derivative PCBM using the stochastic Schrödinger equation (SSE) and reveal the complex time evolution of electron transfer, mediated by electronic coherence and delocalization. By fitting the model to ultrafast charge separation experiments, we estimate the extent of electron delocalization and establish the transition from coherent electron propagation to incoherent hopping. Our results indicate that even a relatively weak coupling between PCBM molecules is sufficient to facilitate electron delocalization and efficient charge separation at organic interfaces.
Published London : Nature Publishing Group
Type Journal article
Language English
Publication date 2016