Molecules undergo a structural change to minimize the energy of excited states generated via external stimuli such as light.This is particularly problematic for Cu(Ⅰ)coordination complexes which are an intriguing alt...Molecules undergo a structural change to minimize the energy of excited states generated via external stimuli such as light.This is particularly problematic for Cu(Ⅰ)coordination complexes which are an intriguing alternative to the rare and expensive transition metal containing complexes(e.g.,Pt,Ir,Ru,etc.)but suffer from short excited state lifetimes due to D_(2d)to D_(2)distortion and solvent coordination.Here we investigate strategic surface binding as an approach to hinder this distortion and increase the excited state lifetime of Cu(Ⅰ)polypyridyl complexes.Using transient absorption spectroscopy,we observe a more than 20-fold increase in excited state lifetime,relative to solution,for a Cu(Ⅰ)complex that can coordinate to the ZrO_(2)via both carboxylated ligands.In contrast,the Cu(Ⅰ)complex that coordinates via only one ligand has a less pronounced enhancement upon surface binding and exhibits greater sensitivity to coordinating solvents.A combination of ATR-IR and polarized visible ATR measurements as well as theoretical calculations suggest that the increased lifetime is due to surface binding which decreases the degrees of freedom for molecular distortion(e.g.,D_(2d)to D_(2)),with the doubly bound complex exhibiting the most pronounced enhancement.展开更多
基金Portions of this work were supported by the National Science Foundation under grant no.CHE-2246932Structural characterization of the film was supported by the Army Research Office under grant no.W911NF-19-1-0357+2 种基金Transient absorption measurements were performed on a spectrometer supported by the National Science Foundation under grant no.CHE-1919633the National Science Foundation under the grant no.CHE-1554855 as well as North Carolina State University,and the computing resources provided by North Carolina State University High Performance Computing Services Core Facility(RRID:SCR 022168)This instrument was supported as part of the Center for Interface Science:Solar-Electric Materials(CIS:SEM),an Energy Frontier Research Center funded by the U.S.Department of Energy,Office of Science,Office of Basic Energy Sciences under Award No.DE-SC0001084.
文摘Molecules undergo a structural change to minimize the energy of excited states generated via external stimuli such as light.This is particularly problematic for Cu(Ⅰ)coordination complexes which are an intriguing alternative to the rare and expensive transition metal containing complexes(e.g.,Pt,Ir,Ru,etc.)but suffer from short excited state lifetimes due to D_(2d)to D_(2)distortion and solvent coordination.Here we investigate strategic surface binding as an approach to hinder this distortion and increase the excited state lifetime of Cu(Ⅰ)polypyridyl complexes.Using transient absorption spectroscopy,we observe a more than 20-fold increase in excited state lifetime,relative to solution,for a Cu(Ⅰ)complex that can coordinate to the ZrO_(2)via both carboxylated ligands.In contrast,the Cu(Ⅰ)complex that coordinates via only one ligand has a less pronounced enhancement upon surface binding and exhibits greater sensitivity to coordinating solvents.A combination of ATR-IR and polarized visible ATR measurements as well as theoretical calculations suggest that the increased lifetime is due to surface binding which decreases the degrees of freedom for molecular distortion(e.g.,D_(2d)to D_(2)),with the doubly bound complex exhibiting the most pronounced enhancement.
