Towards synthetic unimolecular [Fe2S2]-photocatalysts sensitized by perylene dyes

ACS Appl. Mater. Interfaces

et al. 2023

Self Cite

CdSe quantum dots (QDs) combined with [FeFe] hydrogenase mimics as molecular catalytic reaction centers based on earth-abundant elements have demonstrated promising activity for photocatalytic hydrogen generation. Direct linking of the [FeFe] hydrogenase mimics to the QD surface is expected to establish a close contact between the [FeFe] hydrogenase mimics and the light-harvesting QDs, supporting the transfer and accumulation of several electrons needed to drive hydrogen evolution. In this work, we report on the functionalization of QDs immobilized in a thin-film architecture on a substrate with [FeFe] hydrogenase mimics by covalent linking via carboxylate groups as the anchoring functionality. The functionalization was monitored via UV/vis, photoluminescence, IR, and X-ray photoelectron spectroscopy and quantified via micro-X-ray fluorescence spectrometry. The activity of the functionalized thin film was demonstrated, and turn-over numbers in the range of 360–580 (short linkers) and 130–160 (long linkers) were achieved. This work presents a proof-of-concept study, showing the potential of thin-film architectures of immobilized QDs as a platform for light-driven hydrogen evolution without the need for intricate surface modifications to ensure colloidal stability in aqueous environments.

Section: Resultsmentioning

confidence: 80%

Covalent Functionalization of CdSe Quantum Dot Films with Molecular [FeFe] Hydrogenase Mimics for Light-Driven Hydrogen Evolution

Benndorf

Schleusener

ACS Appl. Mater. Interfaces

et al. 2023

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“…These probably form during sample preparation or because of the X-ray irradiation during the measurement. 33 The attachment of the hydrogenase mimics was further confirmed in the C 1s region, which shows signatures of the organic backbone of the catalysts (see SI for further details).…”

mentioning

confidence: 86%

“…According to the binding energy of the Fe 2p3/2 main peak and the satellite peaks, Fe-S bonds were detected. 33 Due to their similar binding energies, these peaks could also relate to Fe-O bonds. 34 In addition, a sulfur signature between both selenium peaks arises.…”

mentioning

confidence: 99%

Covalent functionalization of CdSe quantum dot films with molecular [FeFe] hydrogenase mimics for light-driven hydrogen evolution

Benndorf

Schleusener

et al. 2022

Preprint

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CdSe quantum dots combined with [FeFe] hydrogenase mimics as molecular catalytic reaction centers based on earth abundant elements have demonstrated promising activity for photocatalytic hydrogen generation. Direct linking of the [FeFe] hydrogenase mimics to the quantum dots surface is expected to enhance the activity of the system by establishing close contact between the [FeFe] hydrogenase mimics and the light harvesting quantum dots supporting the transfer and accumulation of several electrons which are needed to drive hydrogen evolution. To circumvent the problem of limited colloidal stability upon covalent functionalization of the quantum dots under optimal pH conditions for hydrogen evolution, in this work, we report on the functionalization of quantum dots immobilized in a thin film architecture on a substrate with [FeFe] hydrogenase mimics by covalent linking via carboxylate groups as anchoring functionality to bind to the QD surface. The functionalization was monitored via UV/Vis absorption, photoluminescence, infrared (ATR-FTIR) and X-ray photoelectron spectroscopy (XPS) and quantified via micro X-ray fluorescence spectrometry (μXRF). The activity of the molecularly functionalized thin film was demonstrated and in dependence on the linker length TONs in the range of 360-580 (short linker) and 130-160 (long linker) were achieved. This work presents a proof of concept study showing the potential of thin film architectures of immobilized quantum dots as platform for light-driven hydrogen evolution and beyond.

“…Peneva et al described the integration of an [FeFe]-hydrogenase cluster into perylene based photosensitizers. [14] Here, we present the synthesis and spectroscopic studies of a novel photocatalyst dyad employing a perylene (Per) photosensitizer (phenPer = 5-(perylen-3-yl)-1,10-phenanthro-line) and ac RhCp* catalyst moiety, namely Rh III phenPer ([(phenPer)Rh(Cp*)Cl]Cl, see Figure 1). A number of previous studies report on the incorporation of [(N^N)Rh(Cp*)Cl] + units (N^N = phen (1,10-phenanthroline) or bpy (2,2'-bipyridine)) in heterogeneous or homogenous catalytic systems.…”

Section: Introductionmentioning

confidence: 99%

“…Peneva et al . described the integration of an [FeFe]‐hydrogenase cluster into perylene based photosensitizers [14] …”

Section: Introductionmentioning

confidence: 99%

Photocatalytic Reduction of Nicotinamide Co‐factor by Perylene Sensitized Rh^III Complexes**

Brückmann

Friedländer

et al. 2022

Chemistry A European J

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The ambitious goal of artificial photosynthesis is to develop active systems that mimic nature and use light to split water into hydrogen and oxygen. Intramolecular design concepts are particularly promising. Herein, we firstly present an intramolecular photocatalyst integrating a perylene‐based light‐harvesting moiety and a catalytic rhodium center (RhIIIphenPer). The excited‐state dynamics were investigated by means of steady‐state and time‐resolved absorption and emission spectroscopy. The studies reveal that photoexcitation of RhIIIphenPer yields the formation of a charge‐separated intermediate, namely RhIIphenPer⋅+, that results in a catalytically active species in the presence of protons.