[institut] Reminder - SCL online seminar: Nenad Vukmirovic, Thursday, 9 December, 14:00

[Antun Balaz]

Dear colleagues,

You are cordially invited to the SCL online seminar of the Center for the Study of Complex Systems, which will be held on Thursday, 9 December 2021 at 14:00 on Zoom (link is given below). The talk entitled

Charge pair transport pathway in organic solar cells

will be given by Dr. Nenad Vukmirović (Scientific Computing Laboratory, Center for the Study of Complex Systems, Institute of Physics Belgrade). Abstract of the talk:

Solar cells based on organic semiconductors have been widely investigated in the last three decades with a continuous improvement in their performance and lifetime and improved understanding of the processes that take place in the device. The first part of the talk will consist of a brief review of this research field and a review of our previous efforts aimed at understanding the key process in the solar cell - the separation of photo-generated charge pairs (excitons). Our recent results will be presented in the second part of the talk [1, 2]. We model the system using a microscopic effective Hamiltonian that takes into account the most relevant processes that determine the dynamics of excitons. The results for energy and time resolved dynamics of charge pairs from the moment of their photogeneration to the moment of their extraction or recombination will be presented. The results indicated that charge separation proceeds via the cold pathway in which donor excitons convert to relaxed charge-transfer excitons which further transform to the states of separated charges [1]. We further analyze these results from the perspective of non-equilibrium thermodynamics. We determine the difference between equilibrium and non-equilibrium dependence of free energy on charge pair separation distance. Our results indicated that this difference is largest when charge separation efficiency is large which led us to conclude that charge separation in efficient organic solar cells proceeds via a cold but nonequilibrated pathway [2].

[1] V. Janković and N. Vukmirović, J. Phys. Chem. C 124, 4378 (2020).
[2] W. Kaiser, V. Janković, N. Vukmirović, and A. Gagliardi, J. Phys. Chem. Lett. 12, 6389 (2021).

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Time: Dec 9, 2021 14:00 Belgrade
https://us02web.zoom.us/j/89949206726?pwd=dEQxejN5YVF6NVo1SitBQzBQR3R4dz09

Meeting ID: 899 4920 6726
Passcode: 819948
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Best regards,
Antun Balaž

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Dr. Antun Balaž
Research Professor

http://www.scl.rs/antun
Phone: +381 11 3713152
Fax: +381 11 3162190

Scientific Computing Laboratory
Center for the Study of Complex Systems

Institute of Physics Belgrade
National Institute of the Republic of Serbia
Pregrevica 118, 11080 Belgrade, Serbia
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