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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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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The Golden Age of Thermally Activated Delayed Fluorescence Materials: Design and Exploitation

Chemical Reviews, Год журнала: 2024, Номер unknown

Опубликована: Дек. 12, 2024

Since the seminal report by Adachi and co-workers in 2012, there has been a veritable explosion of interest design thermally activated delayed fluorescence (TADF) compounds, particularly as emitters for organic light-emitting diodes (OLEDs). With rapid advancements innovation materials design, efficiencies TADF OLEDs each primary color points well white devices now rival those state-of-the-art phosphorescent emitters. Beyond electroluminescent devices, compounds have also found increasing utility applications numerous related fields, from photocatalysis, to sensing, imaging beyond. Following our previous review 2017 (

Язык: Английский

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Blue‐to‐UVB Upconversion, Solvent Sensitization and Challenging Bond Activation Enabled by a Benzene‐Based Annihilator

Angewandte Chemie International Edition, Год журнала: 2022, Номер 62(8)

Опубликована: Ноя. 18, 2022

Several energy-demanding photoreactions require harsh UV light from inefficient sources. The conversion of low-energy visible to high-energy singlet states via triplet-triplet annihilation upconversion (TTA-UC) could offer a solution for driving such reactions under mild conditions. We present the first annihilator with an emission maximum in UVB region that, combined organic sensitizer, is suitable blue-to-UVB upconversion. was successfully employed as energy donor subsequent FRET activations aliphatic carbonyls. This hitherto unreported UC-FRET reaction sequence directly monitored using laser spectroscopy and applied mechanistic irradiation experiments demonstrating feasibility Norrish chemistry. Our results provide clear evidence novel blue light-driven substrate or solvent activation strategy, which important context developing more sustainable light-to-chemical systems.

Язык: Английский

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Sensitizer-controlled photochemical reactivityviaupconversion of red light

Chemical Science, Год журнала: 2022, Номер 14(1), С. 149 - 161

Опубликована: Дек. 1, 2022

By combining the energy input from two red photons, chemical reactions that would normally require blue or ultraviolet irradiation become accessible. Key advantages of this biphotonic excitation strategy are light usually penetrates deeper into complex reaction mixtures and causes less photo-damage than direct illumination in ultraviolet. Here, we demonstrate primary light-absorber a dual photocatalytic system comprised transition metal-based photosensitizer an organic co-catalyst can completely alter outcome. Photochemical reductions achieved with copper(i) presence sacrificial electron donor, whereas oxidative substrate activation occurs osmium(ii) photosensitizer. Based on time-resolved laser spectroscopy, changeover photochemical reactivity is due to different underlying mechanisms. Following triplet transfer 9,10-dicyanoanthracene (DCA) subsequent triplet-triplet annihilation upconversion, fluorescent singlet excited state DCA triggers activation, which initiates

Язык: Английский

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Direct Observation of Triplet States in the Isomerization of Alkenylboronates by Energy Transfer Catalysis

Journal of the American Chemical Society, Год журнала: 2023, Номер 145(39), С. 21576 - 21586

Опубликована: Сен. 20, 2023

Alkenylboronates are versatile building blocks for stereocontrolled synthesis owing to the traceless nature of boron group that can be leveraged achieve highly selective geometric isomerization. Using thioxanthone as an inexpensive photocatalyst, photoisomerization these species continues provide expansive platform stereodivergent synthesis, particularly in construction bioactive polyenes. Although mechanistic investigations consistent with light-driven energy transfer, direct experimental evidence remains conspicuously absent. Herein, we report a rigorous investigation using two widely used alkenylboronates alongside relevant reference compounds. Through combination irradiation experiments, transient absorption spectroscopic studies, kinetic modeling, and DFT calculations all isomers model compounds, it has been possible unequivocally detect characterize perpendicular triplet generated by transfer. Our results serve not only blueprint studies challenging organic sensitizers, but guidelines delineated have also enabled development more sustainable reaction conditions: first time, efficient organocatalytic isomerization under sunlight become feasible.

Язык: Английский

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Triplet-Triplet Annihilation Mediated Photon Upconversion Solar Energy Systems

Materials Chemistry Frontiers, Год журнала: 2023, Номер 7(12), С. 2297 - 2315

Опубликована: Янв. 1, 2023

Triplet–triplet annihilation mediated solar energy harvesting systems for a global transition toward carbon-neutral technologies.

Язык: Английский

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Sensitization-Initiated Electron Transfer Mechanism in Photoredox Catalysis Using a Ru-Py Dyad as a Dual Sensitizer and Reductant

The Journal of Physical Chemistry C, Год журнала: 2025, Номер 129(9), С. 4398 - 4406

Опубликована: Фев. 24, 2025

The sensitization-initiated electron transfer (SenI-ET) mechanism is a well-established concept in photoredox catalysis, yet its kinetic intricacies remain to be fully elucidated. In this study, we have successfully designed and synthesized dyad, Ru(bpy)32+–pyrene (Ru-Py), which functions dually as sensitizer reductant. By the use of rapid intramolecular triplet singlet energy Ru-Py, complex decay pathway SenI-ET process was effectively simplified. Notably, demonstrated that direct from 3Ru*-Py diisopropyl ethylamine generates Ru(I)-Py, further drives catalytic process, rather than reaction being driven by formation Ru-Py•- through Ru-3Py* ethylamine. Furthermore, employed Ru-Py catalyst for C–H oxidation an activated aryl bromide, demonstrating superior efficiency compared conventional Ru(bpy)32+/pyrene system.

Язык: Английский

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Metal–Organic Bichromophore Lowers the Upconversion Excitation Power Threshold and Promotes UV Photoreactions

Journal of the American Chemical Society, Год журнала: 2023, Номер 145(20), С. 11402 - 11414

Опубликована: Май 15, 2023

Sensitized triplet–triplet annihilation upconversion is a promising strategy to use visible light for chemical reactions requiring the energy input of UV photons. This avoids unsafe ultraviolet sources and can mitigate photo-damage provide access reactions, which filter effects hamper direct excitation. Here, we report new approach make blue-to-UV more amenable photochemical applications. The tethering naphthalene unit cyclometalated iridium(III) complex yields bichromophore with high triplet (2.68 eV) naphthalene-based reservoir featuring lifetime 72.1 μs, roughly factor 20 longer than photoactive excited state parent complex. In combination three different annihilators, consistently lower thresholds crossover from quadratic into linear excitation power dependence regime were observed compared system composed 2,5-diphenyloxazole annihilator sufficiently robust under long-term blue irradiation continuously high-energy singlet-excited that drive normally light. Both photoredox transfer catalyses feasible using this concept, including reductive N–O bond cleavage Weinreb amides, C–C coupling reaction based on aryl debromination, two Paternò–Büchi [2 + 2] cycloaddition reactions. Our work seems relevant in context developing strategies driving energetically demanding photochemistry low-energy

Язык: Английский

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First‐Row d⁶ Metal Complex Enables Photon Upconversion and Initiates Blue Light‐Dependent Polymerization with Red Light

Angewandte Chemie International Edition, Год журнала: 2023, Номер 62(43)

Опубликована: Сен. 8, 2023

Photosensitizers for sensitized triplet-triplet annihilation upconversion (sTTA-UC) often rely on precious heavy metals, whereas coordination complexes based abundant first-row transition metals are less common. This is mainly because long-lived triplet excited states more difficult to obtain 3d particularly when the d-subshell only partially filled. Here, we report first example of sTTA-UC a 3d6 metal photosensitizer yielding an performance competitive with metal-based analogues. Using newly developed Cr0 featuring equally good photophysical properties as OsII benchmark complex in combination acetylene-decorated anthracene annihilator, red-to-blue achievable. The efficiency under optimized conditions 1.8 %, and excitation power density threshold reach strong limit 5.9 W/cm2 . These factors, along high photostability, permit initiation acrylamide polymerization by red light, radiative energy transfer between delayed annihilator fluorescence blue light absorbing photo-initiator. Our study provides proof-of-concept photon elusive analogues widely employed d6 photosensitizers, their application photochemical reactions triggered wavelengths close near-infrared.

Язык: Английский

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