Nanoengineering Triplet–Triplet Annihilation Upconversion: From Materials to Real-World Applications

ACS Nano, Год журнала: 2023, Номер 17(4), С. 3259 - 3288

Опубликована: Фев. 17, 2023

Using light to control matter has captured the imagination of scientists for generations, as there is an abundance photons at our disposal. Yet delivering beyond surface many photoresponsive systems proven challenging, particularly scale, due attenuation via absorption and scattering losses. Triplet–triplet annihilation upconversion (TTA-UC), a process which allows low energy be converted high photons, poised overcome these challenges by allowing precise spatial generation its nonlinear nature. With wide range sensitizer annihilator motifs available TTA-UC, researchers seek integrate materials in solution or solid-state applications. In this Review, we discuss nanoengineering deployment strategies highlight their uses recent state-of-the-art examples TTA-UC integrated both Considering implementation tactics application-specific requirements, identify critical needs push TTA-UC-based applications from academic curiosity scalable technology.

Язык: Английский

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Red Light-Based Dual Photoredox Strategy Resembling the Z-Scheme of Natural Photosynthesis

JACS Au, Год журнала: 2022, Номер 2(6), С. 1488 - 1503

Опубликована: Июнь 10, 2022

Photoredox catalysis typically relies on the use of single chromophores, whereas strategies, in which two different light absorbers are combined, rare. In photosystems I and II green plants, separate chromophores P680 P700 both absorb independently one another, then their excitation energy is combined so-called Z-scheme, to drive an overall reaction that thermodynamically very demanding. Here, we adapt this concept perform photoredox reactions organic substrates with input red photons instead blue or UV light. Specifically, a CuI bis(α-diimine) complex combination situ formed 9,10-dicyanoanthracenyl radical anion presence excess diisopropylethylamine catalyzes ca. 50 dehalogenation detosylation reactions. This dual approach seems useful because less damaging has greater penetration depth than radiation. UV-vis transient absorption spectroscopy reveals subtle change solvent from acetonitrile acetone induces changeover mechanism, involving either dominant photoinduced electron transfer triplet-triplet pathway. Our study illustrates mechanistic complexity systems operating under multiphotonic conditions, it provides insights into how competition between desirable unwanted steps can become more controllable.

Язык: Английский

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Visible‐to‐UV Photon Upconversion: Recent Progress in New Materials and Applications

Angewandte Chemie International Edition, Год журнала: 2023, Номер 62(25)

Опубликована: Март 8, 2023

Ultraviolet (UV, λ<400 nm) light is essential for various photochemical reactions, but its intensity in the solar spectrum very low, and sources that artificially generate high-energy UV are inefficient environmentally unfriendly. A solution to this problem photon upconversion (UC) from visible (vis, λ>400 light. Among several mechanisms, UC based on triplet-triplet annihilation (TTA-UC) particular has made remarkable progress recent years. The development of new chromophores enabled highly efficient conversion low-intensity into In review, we summarize visible-to-UV TTA-UC, their production films application processes such as catalysis, bond activation polymerization. Finally, challenges opportunities future material applications will be discussed.

Язык: Английский

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NIR‐Absorbing B,N‐Heteroarene as Photosensitizer for High‐Performance NIR‐to‐Blue Triplet‐Triplet Annihilation Upconversion

Angewandte Chemie International Edition, Год журнала: 2023, Номер 62(25)

Опубликована: Апрель 18, 2023

Triplet-triplet annihilation upconversion (TTA-UC) with near-infrared (NIR) photosensitizers is highly desirable for a variety of emerging applications. However, the development NIR-to-blue TTA-UC large anti-Stokes shift extremely challenging because energy loss during intersystem crossing (ISC). Here, we develop first NIR-absorbing B,N-heteroarene-based sensitizer (BNS) multi-resonance thermally activated delayed fluorescence (MR-TADF) characters to achieve efficient TTA-UC. The small gap between singlet and triplet excited states (0.14 eV) BNS suppresses ISC loss, its long-delayed lifetime (115 μs) contributes transfer. As result, largest (1.03 among all heavy-atom-free NIR-activatable systems obtained high quantum yield 2.9 % (upper limit 50 %).

Язык: Английский

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Cage escape governs photoredox reaction rates and quantum yields

Nature Chemistry, Год журнала: 2024, Номер 16(7), С. 1151 - 1159

Опубликована: Март 18, 2024

Abstract Photoredox catalysis relies on light-induced electron transfer leading to a radical pair comprising an oxidized donor and reduced acceptor in solvent cage. For productive onward reaction occur, the must escape from that cage before they undergo spontaneous reverse transfer. Here we show decisive role plays three benchmark photocatalytic reactions, namely, aerobic hydroxylation, reductive debromination aza-Henry reaction. Using ruthenium(II)- chromium(III)-based photocatalysts, which provide inherently different quantum yields, determined quantitative correlations between rates of photoredox product formation yields. These findings can be largely rationalized within framework Marcus theory for

Язык: Английский

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Challenges and Future Perspectives in Photocatalysis: Conclusions from an Interdisciplinary Workshop

JACS Au, Год журнала: 2024, Номер 4(8), С. 2746 - 2766

Опубликована: Авг. 8, 2024

Photocatalysis is a versatile and rapidly developing field with applications spanning artificial photosynthesis, photo-biocatalysis, photoredox catalysis in solution or supramolecular structures, utilization of abundant metals organocatalysts, sustainable synthesis, plastic degradation. In this Perspective, we summarize conclusions from an interdisciplinary workshop young principal investigators held at the Lorentz Center Leiden March 2023. We explore how diverse fields within photocatalysis can benefit one another. delve into intricate interplay between these subdisciplines, by highlighting unique challenges opportunities presented each multidisciplinary approach drive innovation lead to solutions for future. Advanced collaboration knowledge exchange across domains further enhance potential photocatalysis. Artificial photosynthesis has become promising technology solar fuel generation, instance, via water splitting CO

Язык: Английский

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Factors that Impact Photochemical Cage Escape Yields

Chemical Reviews, Год журнала: 2024, Номер 124(11), С. 7379 - 7464

Опубликована: Май 14, 2024

The utilization of visible light to mediate chemical reactions in fluid solutions has applications that range from solar fuel production medicine and organic synthesis. These are typically initiated by electron transfer between a photoexcited dye molecule (a photosensitizer) redox-active quencher yield radical pairs intimately associated within solvent cage. Many these radicals undergo rapid thermodynamically favored "geminate" recombination do not diffuse out the cage surrounds them. Those escape useful reagents may subsequent important above-mentioned applications. process factors determine yields remain poorly understood despite decades research motivated their practical fundamental importance. Herein, state-of-the-art on light-induced appeared since seminal 1972 review J. P. Lorand entitled "The Cage Effect" is reviewed. This also provides some background for those new field discusses both homolytic bond photodissociation bimolecular induced reactions. concludes with key goals directions future promise elevate this very vibrant even greater heights.

Язык: Английский

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High Triplet Energy Iridium(III) Isocyanoborato Complex for Photochemical Upconversion, Photoredox and Energy Transfer Catalysis

Journal of the American Chemical Society, Год журнала: 2022, Номер 144(2), С. 963 - 976

Опубликована: Янв. 5, 2022

Cyclometalated Ir(III) complexes are often chosen as catalysts for challenging photoredox and triplet-triplet-energy-transfer (TTET) catalyzed reactions, they of interest upconversion into the ultraviolet spectral range. However, triplet energies commonly employed photosensitizers typically limited to values around 2.5-2.75 eV. Here, we report on a new luminophore, with an unusually high energy near 3.0 eV owing modification previously reported complex isocyanoborato ligands. Compared nonborylated cyanido precursor complex, introduction B(C6F5)3 units in second coordination sphere results substantially improved photophysical properties, particular luminescence quantum yield (0.87) long excited-state lifetime (13.0 μs), addition energy. These favorable properties (including good long-term photostability) facilitate exceptionally organic photoreactions (sensitized) triplet-triplet annihilation fluorescent singlet excited state beyond 4 eV, deep region. The photocatalyzes sigmatropic shift [2 + 2] cycloaddition reactions that unattainable common transition metal-based photosensitizers. In presence sacrificial electron donor, it furthermore is applicable demanding photoreductions, including dehalogenations, detosylations, degradation lignin model substrate. Our study demonstrates how rational ligand design transition-metal underexplored effects) can be used enhance their thereby broaden application potential solar conversion synthetic photochemistry.

Язык: Английский

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Best practice in determining key photophysical parameters in triplet–triplet annihilation photon upconversion

Photochemical & Photobiological Sciences, Год журнала: 2022, Номер 21(7), С. 1143 - 1158

Опубликована: Апрель 19, 2022

Triplet-triplet annihilation photon upconversion (TTA-UC) is a process in which low-energy light transformed into of higher energy. During the last two decades, it has gained increasing attention due to its potential in, e.g., biological applications and solar energy conversion. The highest efficiencies for TTA-UC systems have been achieved liquid solution, owing that several intermediate steps require close contact between interacting species, something more easily diffusion-controlled environments. There good understanding kinetics dictating performance systems, but so far, community lacks cohesiveness terms how important parameters are best determined experimentally. In this perspective, we discuss present "best practice" determination critical TTA-UC, namely triplet excited state energies, rate constants triplet-triplet ([Formula: see text]), excited-state lifetimes excitation threshold intensity text]). Finally, introduce newly developed method by [Formula: text], text] may be simultaneously using same set time-resolved emission measurements. experiment can performed with simple experimental setup, ran under mild conditions, entirely circumvents need challenging nanosecond transient absorption measurements, technique previously required extract text]. Our hope discussions methodologies presented herein will aid performing efficient manageable experiments while maintaining-and sometimes increasing-the accuracy validity extracted parameters.

Язык: Английский

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Water-Soluble Tris(cyclometalated) Iridium(III) Complexes for Aqueous Electron and Energy Transfer Photochemistry

Accounts of Chemical Research, Год журнала: 2022, Номер 55(9), С. 1290 - 1300

Опубликована: Апрель 12, 2022

ConspectusCyclometalated iridium(III) complexes are frequently employed in organic light emitting diodes, and they popular photocatalysts for solar energy conversion synthetic chemistry. They luminesce from redox-active excited states that can have high triplet energies long lifetimes, making them well suited transfer photoredox catalysis. Homoleptic tris(cyclometalated) typically very hydrophobic do not dissolve polar solvents, somewhat limiting their application scope. We developed a family of water-soluble sulfonate-decorated variants with tailored redox potentials excited-state to address several key challenges aqueous photochemistry.First, we aimed at combining enzyme catalysis synthesize enantioenriched products cyclic reaction network. Since the biocatalyst operates best solution, photocatalyst was needed. A new complex provided enough reducing power photochemical reduction imines racemic mixtures amines furthermore compatible monoamine oxidase (MAO-N-9), which deracemized this mixture through kinetic resolution amine via oxidation corresponding imine. This process led accumulation unreactive enantiomer over time. In subsequent studies, discovered same photoionizes under intense irradiation give hydrated electrons as result consecutive two-photon excitation. With visible input, become available catalytic fashion, thereby allowing comparatively mild substrates would only be reactive harsher conditions. Finally, became interested upconversion it desirable obtain compounds energies. goal achieved improved ligand design ultimately enabled sensitized triplet–triplet annihilation unusually far into ultraviolet spectral range.Studies catalysis, rely on use solvents. Water could potentially an attractive alternative many cases, but development lags behind solution compared solvent. The purpose Account is provide overview breadth research perspectives emerged fac-[Ir(ppy)]3 (ppy = 2-phenylpyridine) sulfonated ligands. hope inspire some these or related coordination photochemistry stimulate further conceptual developments interfaces chemistry, photophysics, biocatalysis, sustainable

Язык: Английский

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