Recharging Upconversion: Revealing Rubrene’s Replacement

One of the major limitations of solid-state perovskite-sensitized photon upconversion to date is that the only annihilator successfully paired with the perovskite sensitizer has been rubrene, raising the question of whether this approach of triplet sensitization is universal or limited in scope. Additionally, the inherent energetic mismatch between the perovskite bandgap and the rubrene triplet energy has restricted the apparent anti-Stokes shift achievable in the upconversion process. To increase the apparent anti-Stokes shift for upconversion processes, anthracene derivates are of particular interest due to their deeper highest occupied molecular orbital levels and higher triplet energies. Here, we demonstrate successful sensitization of the triplet level of 1-chloro-9,10-bis(phenylethynyl)anthracene using the established formamidinium methylammonium lead triiodide perovskite, resulting in upconverted emission at 550 nm under 780 nm excitation. We draw a direct comparison to rubrene to unravel the underlying differences in the upconversion processes.