title: Accessing the Long-Lived Triplet Excited States in Transition-Metal Complexes: Molecular Design Rationales and Applications.
abstract: Transition-metal complex triplet photosensitizers are versatile compounds that have been widely used in photocatalysis, photovoltaics, photodynamic therapy (PDT) and triplet-triplet annihilation (TTA) upconversion. The principal photophysical processes in these applications are the intermolecular energy transfer or electron transfer. One of the major challenges facing these triplet photosensitizers is the short triplet-state lifetime, which is detrimental to the above-mentioned photophysical processes. In order to address this challenge, transition-metal complexes showing long-lived triplet excited states are highly desired. This review article summarizes the development of this fascinating area, including the molecular design rationales, the principal photophysical properties, and the applications of these complexes in PDT and TTA upconversion.
authors.affiliation: State Key Laboratory of Fine Chemicals, School of Chemical Engineering, Dalian University of Technology, E-208 Western Campus, 2 Ling-Gong Road, Dalian, 116024, P. R. China.
authors.forename: Xiaoneng
authors.initials: X
authors.lastname: Cui
authors.affiliation: State Key Laboratory of Fine Chemicals, School of Chemical Engineering, Dalian University of Technology, E-208 Western Campus, 2 Ling-Gong Road, Dalian, 116024, P. R. China.
authors.forename: Jianzhang
authors.initials: J
authors.lastname: Zhao
authors.affiliation: State Key Laboratory of Fine Chemicals, School of Chemical Engineering, Dalian University of Technology, E-208 Western Campus, 2 Ling-Gong Road, Dalian, 116024, P. R. China.
authors.forename: Zafar
authors.initials: Z
authors.lastname: Mohmood
authors.affiliation: State Key Laboratory of Fine Chemicals, School of Chemical Engineering, Dalian University of Technology, E-208 Western Campus, 2 Ling-Gong Road, Dalian, 116024, P. R. China.
authors.forename: Caishun
authors.initials: C
authors.lastname: Zhang
keywords: chromophores; photochemistry; sensitizers; transition metals; triplet states