Optimizing photon upconversion by decoupling excimer formation and triplet triplet annihilation
Artikel i vetenskaplig tidskrift, 2020

Perylene is a promising annihilator candidate for triplet-triplet annihilation photon upconversion, which has been successfully used in solar cells and in photocatalysis. Perylene can, however, form excimers, reducing the energy conversion efficiency and hindering further development of TTA-UC systems. Alkyl substitution of perylene can suppress excimer formation, but decelerate triplet energy transfer and triplet-triplet annihilation at the same time. Our results show that mono-substitution with small alkyl groups selectively blocks excimer formation without severly compromising the TTA-UC efficiency. The experimental results are complemented by DFT calculations, which demonstrate that excimer formation is suppressed by steric repulsion. The results demonstrate how the chemical structure can be modified to block unwanted intermolecular excited state relaxation pathways with minimal effect on the preferred ones.

Författare

Chen Ye

Göteborgs universitet

Victor Gray

University of Cambridge

Uppsala universitet

Khushbu Kushwaha

Göteborgs universitet

Sandeep Kumar Singh

Chalmers, Fysik, Material- och ytteori

Paul Erhart

Chalmers, Fysik, Kondenserad materie- och materialteori

Karl Börjesson

Göteborgs universitet

Physical Chemistry Chemical Physics

1463-9076 (ISSN) 1463-9084 (eISSN)

Vol. 22 3 1715-1720

Ämneskategorier

Annan fysik

Teoretisk kemi

Organisk kemi

DOI

10.1039/c9cp06561j

PubMed

31895392

Mer information

Senast uppdaterat

2020-06-02