Two Birds, One Stone: Microsecond Dark Excited-State Lifetime and Large Cage Escape Yield Afforded by an Iron–Anthracene Molecular Dyad

Journal of the American Chemical Society, Год журнала: 2025, Номер unknown

Опубликована: Фев. 28, 2025

Iron photosensitizers represent a holy grail in photochemistry, but their widespread implementation is limited by short excited-state lifetimes and poor cage escape yields. Here, the introduction of an anthracene moiety appended to iron(III) complex allowed solve both limitations generate novel dyad exhibiting extraordinary lifetime 11.5 μs. The key achieving this remarkably long depopulation short-lived iron-centered emissive excited state populate dark triplet located on anthracene-like with spin-forbidden deactivation. Population only occurs ∼10% efficiency acetonitrile still allows expansion scope reactivity accessible iron-based photosensitizers, which now encompasses energy transfer 3O2. In addition, proof-of-principle investigation methyl viologen as electron acceptor, population drastic ten-fold increase yield from 4.5% for unsubstituted 42% molecular dyad. Hence, new provides complementary approach complexes based first-row transition metals alternatives well-established analogues precious metals. We believe that further spectroscopic investigations synthetic modifications acceptor linkage photosensitizer will be use these innovative dyads applications near future.

Язык: Английский

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Iron(III) Complexes with Luminescence Lifetimes of up to 100 ns to Enhance Upconversion and Photocatalysis

Journal of the American Chemical Society, Год журнала: 2025, Номер unknown

Опубликована: Фев. 28, 2025

Iron is the most abundant transition metal element and would be ideal replacement for noble metals in many applications that rely on luminescent long-lived electronically excited states. We show efficient reversible energy transfer between doublet states of iron complexes triplet organic ligands improves storage by up to 350-fold. As a result, luminescence lifetimes 100 ns are achieved, upconversion from red blue light becomes 68 times more yield benchmark photoredox reactions significantly improved. These advances make coordination compounds promising candidates lighting, solar conversion photocatalysis.

Язык: Английский

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Towards a more Sustainable Photocatalysis using Copper and Iron

Current Opinion in Green and Sustainable Chemistry, Год журнала: 2025, Номер unknown, С. 100998 - 100998

Опубликована: Янв. 1, 2025

Язык: Английский

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Manganese Complexes with Consecutive Mn(IV) → Mn(III) Excitation for Versatile Photoredox Catalysis

Journal of the American Chemical Society, Год журнала: 2024, Номер 146(35), С. 24515 - 24525

Опубликована: Июль 30, 2024

Manganese complexes stand out as promising candidates for photocatalyst design, attributed to their eco- and biocompatibility, versatile valence states, capability facilitating multiple electronic excitations. However, several intrinsic constraints, such inadequate visible light response short excited-state lifetimes, hinder effective photoinduced electron transfer impede photoredox activation of substrates. To overcome this obstacle, we have developed a class manganese featuring boron-incorporated

Язык: Английский

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Luminescent Fe(III) Complex Sensitizes Aerobic Photon Upconversion and Initiates Photocatalytic Radical Polymerization

Journal of the American Chemical Society, Год журнала: 2024, Номер unknown

Опубликована: Дек. 10, 2024

Light energy conversion often relies on photosensitizers with long-lived excited states, which are mostly made of precious metals such as ruthenium or iridium. Photoactive complexes based highly abundant iron seem attractive for sustainable conversion, but this remains very challenging due to the short state lifetimes current complexes. This study shows that a luminescent Fe(III) complex sensitizes triplet-triplet annihilation upconversion anthracene derivatives via underexplored doublet-triplet transfer, is assisted by preassociation between photosensitizer and annihilator. In presence an organic mediator, green-to-blue efficiency Φ

Язык: Английский

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Photon upconversion in Bi3Ti2O8F:Yb3+, Er3+ Nanoplates for enhanced near-infrared light harvesting and their application in wastewater purification

Journal of environmental chemical engineering, Год журнала: 2025, Номер unknown, С. 115661 - 115661

Опубликована: Фев. 1, 2025

Язык: Английский

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A Blessing and a Curse: Remote Ligand Functionalization Modulates ³MLCT Relaxation in Group 6 Tricarbonyl Complexes

Inorganic Chemistry, Год журнала: 2025, Номер unknown

Опубликована: Фев. 25, 2025

We recently reported a molecular design for carbonylpyridine molybdenum(0) complexes that unlocks long-lived luminescent and photoactive charge-transfer states. Here, we translate this strategy to chromium(0), tungsten(0) report three fully characterized tricarbonyl metal(0) featuring tripodal ligand with remote n-butyl substituent in the backbone. All show phosphorescence red near-infrared spectral region from metal-to-ligand excited Surprisingly, alkyl chain significantly affects state relaxation: lifetimes are shortened solution but extended solid by one order of magnitude compared complex methyl substituent. Temperature-dependent luminescence NMR spectroscopy combination quantum chemical calculations reveal reasons these disparate effects. The distorts metal coordination geometry. resulting structural flexibility flattens potential energy surfaces solution, which lowers barrier population distorted metal-centered states facilitates nonradiative relaxation. In state, rigidified separates neighboring molecules, reduces self-quenching. Our study sheds light on relationship between structure relaxation inform development based earth-abundant metals.

Язык: Английский

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Cyclometallated Co(III) Complexes with Lowest-Energy Charge Transfer Excited States Accessible with Visible Light

Journal of the American Chemical Society, Год журнала: 2025, Номер unknown

Опубликована: Апрель 10, 2025

The Co(III) complexes, cis-[Co(ppy)2(L)]PF6, where ppy = 2-phenylpyridine and L bpy (2,2'-bipyridine; 1), phen (1,10-phenanthroline; 2), DAP (1,12-diazaperylene; 3), are reported their photophysical properties were investigated to evaluate potential as sensitizers for applications that include solar energy conversion schemes photoredox catalysis. Calculations show cyclometallation in the cis-[Co(ppy)2(L)]PF6 series affords strong Co(dπ)/ppy(π) orbital interactions result a Co/ppy(π*) highest occupied molecular (HOMO) lowest unoccupied (LUMO) localized on diimine ligand, L(π*). Complexes 1-3 exhibit relatively invariant oxidation potentials, whereas reduction event is dependent identity of L, consistent with theoretical predictions. For 3 broad → L(π*) metal/ligand-to-ligand charge transfer (ML-LCT) absorption band observed CH3CN maxima at 507 nm, extending beyond 600 nm. Upon excitation 1ML-LCT transition, transient features population 3ML-LCT excited state lifetimes, τ, 3.0 ps, 4.6 42 ps 1, 2 respectively observed. irradiation 505 able reduce methyl viologen (MV2+), an electron acceptor commonly photocatalytic schemes. To our knowledge, represents first heteroleptic complex combines ligand lowest-lying metal-to-ligand states undergo photoinduced low-energy green light. As such, structural design important step toward d6 photosensitizers based earth abundant metals.

Язык: Английский

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A Near-Infrared-II Luminescent and Photoactive Vanadium(II) Complex with a 760 ns Excited State Lifetime

Journal of the American Chemical Society, Год журнала: 2025, Номер unknown

Опубликована: Июнь 3, 2025

Ruthenium and iridium are key components in the most important applications of photoactive complexes, namely, light-emitting devices, photocatalysis, bioimaging, biosensing, photodynamic therapy. Especially, near-infrared (NIR) emissive materials required fiber-optic telecommunications, anticounterfeit inks, night-vision readable displays, bioimaging. Replacing rare expensive precious metals with more abundant first-row transition is great interest; however, photophysical properties chemical stability 3d metal complexes often insufficient. Here, we tackle these challenges a nonprecious polypyridine vanadium(II) complex that shows emission above 1300 nm excited state lifetimes up to 760 ns. Strong light absorption visible spectral region exceptional presence oxygen enable photocatalysis water acetonitrile using green orange-red for excitation. This study unravels new design principle NIR-II luminescent based on vanadium.

Язык: Английский

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Isostructural Series of a Cyclometalated Iron Complex in Three Oxidation States

Inorganic Chemistry, Год журнала: 2024, Номер 63(37), С. 16964 - 16980

Опубликована: Сен. 2, 2024

An isostructural series of Fe

Язык: Английский

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