Exciton Delocalization Across the Organic Spacer: Origin of Ultrafast Energy Funnelling in Ruddlesden-Popper Perovskites

Sankaran Ramesh^a^,^b, David Giovanni^a, Marcello Righetto^a^,^c, Jia Wei Melvin Lim^a^,^b, Qiannan Zhang^a, Yue Wang^a, Senyun Ye^a, Qiang Xu^a, Nripan Mathews^d^,^e, Tze Chien Sum^a

^aNTU Singapore - Nanyang Technological University, Division of Physics and Applied Physics, School of Physical and Mathematical Sciences, Nanyang Link, 21, Singapore, Singapore

^bEnergy Research Institute @NTU (ERI@N), Interdisciplinary Graduate Programme, Nanyang Technological University, Singapore

^cDepartment of Physics and Astronomy and London Centre for Nanotechnology, University College London, United Kingdom

^dEnergy Research Institute / Nanyang Technological University, Singapore, Singapore

^eNTU Singapore - Nanyang Technological University, School of Materials Science and Engineering, Nanyang Avenue, 50, Singapore, Singapore

International Conference on Hybrid and Organic Photovoltaics
Proceedings of 13th Conference on Hybrid and Organic Photovoltaics (HOPV21)

Online, Spain, 2021 May 24th - 28th

Organizers: Marina Freitag, Feng Gao and Sam Stranks

Oral, Sankaran Ramesh, presentation 054
Publication date: 11th May 2021

Two-dimensional (2D) lead halide Ruddlesden-Popper perovskites (RPP) recently emerged as a prospective material system for optoelectronic applications. Their self-assembled multi quantum-well structure gives rise to the novel inter-well energy funnelling phenomenon, which is of broad interests for photovoltaics, light-emission applications and in emerging technologies (e.g., spintronics). Herein, we developed a realistic finite quantum-well superlattice model that corroborates the hypothesis of exciton delocalization across different quantum-wells in RPP. Such delocalization leads to a sub-50 fs coherent energy transfer between adjacent wells, with the efficiency depending on the RPP phase matching and the organic large cation barrier lengths. Our approach provides a coherent and comprehensive account for both steady-state and transient dynamical experimental results in RPPs. Importantly, these findings pave the way for a deeper understanding of the physics underpinning these systems crucial for establishing materials design-rules to realize efficient RPP-based devices.Two-dimensional (2D) lead halide Ruddlesden-Popper perovskites (RPP) recently emerged as a prospective material system for optoelectronic applications. Their self-assembled multi quantum-well structure gives rise to the novel inter-well energy funnelling phenomenon, which is of broad interests for photovoltaics, light-emission applications and in emerging technologies (e.g., spintronics). Herein, we developed a realistic finite quantum-well superlattice model that corroborates the hypothesis of exciton delocalization across different quantum-wells in RPP. Such delocalization leads to a sub-50 fs coherent energy transfer between adjacent wells, with the efficiency depending on the RPP phase matching and the organic large cation barrier lengths. Our approach provides a coherent and comprehensive account for both steady-state and transient dynamical experimental results in RPPs. Importantly, these findings pave the way for a deeper understanding of the physics underpinning these systems crucial for establishing materials design-rules to realize efficient RPP-based devices.

References:

[1] Giovanni D, Ramesh S, Righetto M, Melvin Lim JW, Zhang Q, Wang Y, Ye S, Xu Q, Mathews N, Sum TC. The Physics of Interlayer Exciton Delocalization in Ruddlesden–Popper Lead Halide Perovskites. Nano Lett. 2021, 21, 1, 405–413

Acknowledgements:

NTU Singapore start-up grant (M4080514)

Ministry of Education AcRF Tier 1 grant (RG91/19)

Ministry of Education Tier 2 grant (MOE2016-T2-1-034)

Ministry of Education Tier 2 grant (MOE2017-T2-1-001)

Ministry of Education Tier 2 grant (MOE2017-T2-2-002)

National Research Foundation(NRF) Singapore under its Competitive Research Program(NRF-CRP14-2014-03)

NRF Investigatorship (NRF-NRFI-2018-04)

nanoGe is a prestigious brand of successful science conferences that are developed along the year in different areas of the world since 2009. Our worldwide conferences cover cutting-edge materials topics like perovskite solar cells, photovoltaics, optoelectronics, solar fuel conversion, surface science, catalysis and two-dimensional materials, among many others.

MATSUS

Previously nanoGe Spring Meeting (NSM) and nanoGe Fall Meeting (NFM), MATSUS is a multiple symposia conference focused on a broad set of topics of advanced materials preparation, their fundamental properties, and their applications, in fields such as renewable energy, photovoltaics, lighting, semiconductor quantum dots, 2-D materials synthesis, charge carriers dynamics, microscopy and spectroscopy semiconductors fundamentals, etc.

International Conference on Hybrid and Organic Photovoltaics

International Conference on Hybrid and Organic Photovoltaics (HOPV) is celebrated yearly in May. The main topics are the development, function and modeling of materials and devices for hybrid and organic solar cells. The field is now dominated by perovskite solar cells but also other hybrid technologies, as organic solar cells, quantum dot solar cells, and dye-sensitized solar cells and their integration into devices for photoelectrochemical solar fuel production.

Asia-Pacific International Conference on Perovskite, Organic Photovoltaics and Optoelectronics

The main topics of the Asia-Pacific International Conference on Perovskite, Organic Photovoltaics and Optoelectronics (IPEROP) are discussed every year in Asia-Pacific for gathering the recent advances in the fields of material preparation, modeling and fabrication of perovskite and hybrid and organic materials. Photovoltaic devices are analyzed from fundamental physics and materials properties to a broad set of applications. The conference also covers the developments of perovskite optoelectronics, including light-emitting diodes, lasers, optical devices, nanophotonics, nonlinear optical properties, colloidal nanostructures, photophysics and light-matter coupling.

International Conference on Perovskite Thin Film Photovoltaics Perovskite Photonics and Optoelectronics

The International Conference on Perovskite Thin Film Photovoltaics Perovskite Photonics and Optoelectronics (NIPHO) is the best place to hear the latest developments in perovskite solar cells as well as on recent advances in the fields of perovskite light-emitting diodes, lasers, optical devices, nanophotonics, nonlinear optical properties, colloidal nanostructures, photophysics and light-matter coupling.