Philip Jiale Feng

Philip Jiale Feng

Optoelectronics Physicist | Postdoc Fellow at Australian Research Council Centre of Excellence in Exciton Science | Alumni at the Cavendish Laboratory, University of Cambridge | World traveller | Piano lover | Art core in a science shell

Bi-excitonic Interactions in Singlet Fission and Triplet-Triplet Annihilation of Organic Molecules

Singlet fission (SF) and triplet-triplet annihilation (TTA) are two processes that can be harnessed to improve the efficiency of conventional inorganic solar cells, such as silicon, and to break the Shockley-Queisser limit on the efficiency of single-junction photovoltaics. However, the mechanism is still under debate, centering around the multi-excitonic states bridging the conversion between spin-singlet and spin-triplet excitons. The aim of this project is to reconcile the debate in previous literature and to establish a unified model to explain the intermediate states in SF and TTA.

If you want to learn more about the triplet-triplet annihilation (TTA) and photochemical energy upconversion, you can read our perspective paper published in Journal of Materials Chemistry C and our review paper published in Annual Review of Physical Chemistry.

Upconversion picture Image: Energy upconversion in solution. The low-energy incoming photons (green laser) are energy upconverted to high-energy photons (violet emission) via triplet-triplet annihilation (TTA).