Optical excitations in semiconductors lead to generation of singlet excitons. Singlet fission has been found to be a mechanism that can result in singlet to triplet exciton conversion. Singlet fission in pentacene is extraordinarily rapid which is therefore considered as the major decay channel for the photoexcited singlet exciton. And the triplet excitons created via singlet fission can dissociate at interfaces with a suitable electron acceptor, such as fullerenes, resulting in free carriers. This has potential in increasing the efficiency of solar cells. In this talk, I will discuss about singlet and triplet exciton dynamics in organic semiconductor with transient absorption experiments and charge generation from fission of singlet excitons.
Mark W. B. Wilson, Akshay Rao, Bruno Ehrler, and Richard H. Friend, Accounts of Chemical Research, Vol. 46, No. 6, 1330–1338 (2013)
Mark W. B. Wilson, Akshay Rao, Jenny Clark, R. Sai Santosh Kumar, Daniele Brida Giulio Cerullo, andRichard H. Friend, J. Am. Chem. Soc., 133, 11830–11833, (2011)