Ultrafast Vibrational Control of Hybrid Perovskite Devices Reveals the Influence of the Organic Cation on Electronic Dynamics

Nathaniel. P. Gallop; Dmitry R. Maslennikov; Katelyn P. Goetz; Zhenbang Dai; Aaron M. Schankler; Woongmo Sung; Satoshi Nihonyanagi; Tahei Tahara; Maryna Bodnarchuk; Maksym Kovalenko; Yana Vaynzof; Andrew M. Rappe; Artem A. Bakulin

arXiv · 2404.14424

Ultrafast Vibrational Control of Hybrid Perovskite Devices Reveals the Influence of the Organic Cation on Electronic Dynamics

Nathaniel. P. Gallop·Dmitry R. Maslennikov·Katelyn P. Goetz·Zhenbang Dai·Aaron M. Schankler·Woongmo Sung·Satoshi Nihonyanagi·Tahei Tahara·Maryna Bodnarchuk·Maksym Kovalenko·Yana Vaynzof·Andrew M. Rappe·Artem A. Bakulin

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Abstract

Vibrational control (VC) of photochemistry through the optical stimulation of structural dynamics is a nascent concept only recently demonstrated for model molecules in solution. Extending VC to state-of-the-art materials may lead to new applications and improved performance for optoelectronic devices. Metal halide perovskites are promising targets for VC due to their mechanical softness and the rich array of vibrational motions of both their inorganic and organic sublattices. Here, we demonstrate the ultrafast VC of FAPbBr3 perovskite solar cells via intramolecular vibrations of the formamidinium cation using spectroscopic techniques based on vibrationally promoted electronic resonance. The observed short (~300 fs) time window of VC highlights the fast dynamics of coupling between the cation and inorganic sublattice. First-principles modelling reveals that this coupling is mediated by hydrogen bonds that modulate both lead halide lattice and electronic states. Cation dynamics modulating this coupling may suppress non-radiative recombination in perovskites, leading to photovoltaics with reduced voltage losses.

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Nathaniel. P. Gallop, Dmitry R. Maslennikov, Katelyn P. Goetz, Zhenbang Dai, Aaron M. Schankler, Woongmo Sung, Satoshi Nihonyanagi, Tahei Tahara, Maryna Bodnarchuk, Maksym Kovalenko, Yana Vaynzof, Andrew M. Rappe, Artem A. Bakulin. 2024-04-17. Ultrafast Vibrational Control of Hybrid Perovskite Devices Reveals the Influence of the Organic Cation on Electronic Dynamics. https://arxiv.org/abs/2404.14424

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