Front Cover: Near‐Infrared‐to‐Visible Photon Upconversion by Introducing an S−T Absorption Sensitizer into a Metal‐Organic Framework (ChemNanoMat 6/2020)

Near-infrared (NIR)-to-visible photon upconversion based on triplet-triplet annihilation (TTA-UC) in the solid-state remains a great challenge due to the sensitizer aggregation that impedes the efficient triplet energy transfer from the sensitizer to the emitter. Herein, a molecular sensitizer exhibiting direct singlet-to-triplet (S–T) absorption was successfully introduced into a new emitter-based metal-organic framework (MOF), resulting in an efficient triplet sensitization and a NIR-to-visible TTA-UC in the solid-state. More information can be found in the Full Paper by Nobuhiro Yanai, Nobuo Kimizuka et al.