Photodriven Ammonia Synthesis from Manganese Nitrides: Photophysics and Mechanistic Investigations

Journal of the American Chemical Society, Год журнала: 2024, Номер 146(40), С. 27610 - 27621

Опубликована: Сен. 27, 2024

Ammonia synthesis from N,N,O,O-supported manganese(V) nitrides and 9,10-dihydroacridine using proton-coupled electron transfer visible light irradiation in the absence of precious metal photocatalysts is described. While reactivity nitride correlated with increased absorption blue light, excited-state lifetimes determined by transient were on order picoseconds. This eliminated manganese as responsible for bimolecular N-H bond formation. Spectroscopic measurements hydrogen source, dihydroacridine, demonstrated that photooxidation was necessary productive ammonia synthesis. Transient pulse radiolysis data dihydroacridine provided evidence presence intermediates weak E-H bonds, including dihydroacridinium radical cation both isomers monohydroacridine radical, but notably these unreactive toward atom net Additional optimization reaction conditions higher photon flux resulted rates production due to activation dihydroacridine.

Язык: Английский

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Functionalized Terthiophene as an Ambipolar Redox System: Structure, Spectroscopy, and Switchable Proton-Coupled Electron Transfer

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

Опубликована: Янв. 27, 2025

Organic redox systems that can undergo oxidative and reductive (ambipolar) electron transfer are elusive yet attractive for applications across synthetic chemistry energy science. Specifically, the use of ambipolar in proton-coupled (PCET) reactions is largely unexplored but could enable "switchable" reactivity wherein uptake release hydrogen atoms controlled using a stimulus. Here, we describe synthesis characterization an functionalized terthiophene (TTH) bearing methyl thioether phosphine oxide groups exhibits switchable PCET reactivity. Electrochemical studies established TTH be reversibly oxidized reduced, prompting cationic anionic radicals on single platform. Combined structural, spectroscopic, computational investigations revealed influence moieties electronic structure results stabilization both radicals. Upon single-electron oxidation, serves as atom acceptor undergoes with 1,4-dihydroquinone to generate hydroxyphosphonium species. The process was found reversible upon reduction, acting donor reaction 2,3-dimethylanthraquinone. thermochemistry O–H bond formed cleaved during sequence investigated, revealing weakening 30 kcal/mol underpins Overall, these provide electrochemical, thermochemical foundation ambipolarity control organic systems.

Язык: Английский

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Photodriven Carbon Nitride Nanosheet-Bacterium Biohybrid with an Encapsulation Structure for CO₂ to C₄ Bioplastic Conversion

ACS Sustainable Chemistry & Engineering, Год журнала: 2025, Номер unknown

Опубликована: Май 6, 2025

Язык: Английский

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Self-Template Impregnated Silver Nanoparticles in Coordination Polymer Gel: Photocatalytic CO2 Reduction, CO2 Fixation, and Antibacterial Activity

Nanoscale, Год журнала: 2024, Номер unknown

Опубликована: Ноя. 1, 2024

CO 2 fixation and light-assisted conversion of in the presence water into fuels feedstocks are clean sustainable techniques to alleviate energy crisis global climate change.

Язык: Английский

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Closing the Loop in the Carbon Cycle: Enzymatic Reactions Housed in Metal–Organic Frameworks for CO2 Conversion to Methanol

Applied Biochemistry and Biotechnology, Год журнала: 2024, Номер unknown

Опубликована: Ноя. 26, 2024

Язык: Английский

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