Covalent Chemistry on a Van Der Waals Heterostructure

The building of van der Waals heterostructures and the decoration of 2D materials with organic molecules share a common goal: to obtain ultrathin materials with tailored properties. Performing controlled chemistry on van der Waals heterostructures would add an extra level of complexity, providing a pathway towards 2D-2D-0D mixed-dimensional heterostructures. Here we show that thiol-ene-like “click” chemistry can be used to decorate franckeite, a naturally occurring van der Waals heterostructure, with maleimide reagents. ATR-IR and NMR analyses corroborate the Michael addition mechanism via the formation of a S-C covalent bond, while Raman and HR-TEM show that the SnS2-PbS alternating structure of franckeite is preserved, and suggest that SnS2reacts preferentially, which is confirmed through XPS. We illustrate how this methodology can be used to add functional molecular moieties by decorating franckeite with porphyrins. UV-vis-NIR spectroscopy confirms that the chromophore remains operative and shows negligible electronic interactions with franckeite in the ground state, while its fluorescence is strongly quenched upon photoexcitation.

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Covalent Chemistry on a Van Der Waals Heterostructure

10.26434/chemrxiv.9878870.v1 ◽

2019 ◽

Author(s):

Julia Villalva ◽

Sara Moreno ◽

Palmira Villa ◽

Luisa R. González ◽

Andres Castellanos-Gomez ◽

...

Keyword(s):

Organic Molecules ◽

Van Der Waals ◽

Covalent Bond ◽

Nir Spectroscopy ◽

Common Goal ◽

Van Der Waals Heterostructures ◽

Electronic Interactions ◽

Naturally Occurring ◽

Van Der Waals Heterostructure ◽

The Michael Addition

The building of van der Waals heterostructures and the decoration of 2D materials with organic molecules share a common goal: to obtain ultrathin materials with tailored properties. Performing controlled chemistry on van der Waals heterostructures would add an extra level of complexity, providing a pathway towards 2D-2D-0D mixed-dimensional heterostructures. Here we show that thiol-ene-like “click” chemistry can be used to decorate franckeite, a naturally occurring van der Waals heterostructure, with maleimide reagents. ATR-IR and NMR analyses corroborate the Michael addition mechanism via the formation of a S-C covalent bond, while Raman and HR-TEM show that the SnS2-PbS alternating structure of franckeite is preserved, and suggest that SnS2reacts preferentially, which is confirmed through XPS. We illustrate how this methodology can be used to add functional molecular moieties by decorating franckeite with porphyrins. UV-vis-NIR spectroscopy confirms that the chromophore remains operative and shows negligible electronic interactions with franckeite in the ground state, while its fluorescence is strongly quenched upon photoexcitation.

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Covalent Chemistry on a Van Der Waals Heterostructure

10.26434/chemrxiv.9878870.v2 ◽

2019 ◽

Cited By ~ 1

Author(s):

Julia Villalva ◽

Sara Moreno ◽

Palmira Villa ◽

Luisa R. González ◽

Cristina Navío ◽

...

Keyword(s):

Organic Molecules ◽

Van Der Waals ◽

Covalent Bond ◽

Nir Spectroscopy ◽

Common Goal ◽

Van Der Waals Heterostructures ◽

Electronic Interactions ◽

Naturally Occurring ◽

Van Der Waals Heterostructure ◽

The Michael Addition

The building of van der Waals heterostructures and the decoration of 2D materials with organic molecules share a common goal: to obtain ultrathin materials with tailored properties. Performing controlled chemistry on van der Waals heterostructures would add an extra level of complexity, providing a pathway towards 2D-2D-0D mixed-dimensional heterostructures. Here we show that thiol-ene-like “click” chemistry can be used to decorate franckeite, a naturally occurring van der Waals heterostructure, with maleimide reagents. ATR-IR and NMR analyses corroborate the Michael addition mechanism via the formation of a S-C covalent bond, while Raman and HR-TEM show that the SnS2-PbS alternating structure of franckeite is preserved, and suggest that SnS2reacts preferentially, which is confirmed through XPS. We illustrate how this methodology can be used to add functional molecular moieties by decorating franckeite with porphyrins. UV-vis-NIR spectroscopy confirms that the chromophore remains operative and shows negligible electronic interactions with franckeite in the ground state, while its fluorescence is strongly quenched upon photoexcitation.

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Covalent modification of franckeite with maleimides: connecting molecules and van der Waals heterostructures

Nanoscale Horizons ◽

10.1039/d1nh00147g ◽

2021 ◽

Author(s):

Julia Villalva ◽

Sara Moreno-Da Silva ◽

Palmira Villa ◽

Luisa Ruiz-González ◽

Cristina Navío ◽

...

Keyword(s):

Click Chemistry ◽

Van Der Waals ◽

Covalent Modification ◽

Van Der Waals Heterostructures ◽

Naturally Occurring ◽

Van Der Waals Heterostructure

We show that thiol–ene-like “click” chemistry can be used to decorate franckeite, a naturally occurring van der Waals heterostructure with maleimide reagents. In this way, we provide a pathway towards 2D–2D–0D mixed-dimensional heterostructures.

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Tuning the excited-state deactivation pathways of dinuclear ruthenium(ii) 2,2′-bipyridine complexes through bridging ligand design

Dalton Transactions ◽

10.1039/d0dt01216e ◽

2020 ◽

Vol 49 (24) ◽

pp. 8096-8106 ◽

Cited By ~ 2

Author(s):

Simon Cerfontaine ◽

Ludovic Troian-Gautier ◽

Sara A. M. Wehlin ◽

Frédérique Loiseau ◽

Emilie Cauët ◽

...

Keyword(s):

Excited State ◽

Steady State ◽

Variable Temperature ◽

Ligand Design ◽

Binuclear Complexes ◽

Time Resolved ◽

Bridging Ligand ◽

Dinuclear Ruthenium ◽

Photophysical Study ◽

Time Resolved Photoluminescence

A detailed photophysical study of binuclear complexes was performed using steady-state and time-resolved photoluminescence measurements at variable temperature. The results were compared with the prototypical [Ru(bpy)3]2+.

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Spectral and Photoprototropic Characteristics of 4-Aminobiphenyl in β-Cyclodextrin

Collection of Czechoslovak Chemical Communications ◽

10.1135/cccc20040748 ◽

2004 ◽

Vol 69 (4) ◽

pp. 748-758 ◽

Cited By ~ 16

Author(s):

Israel V. Muthu Vijayan Enoch ◽

Meenakshisundaram Swaminathan

Keyword(s):

Excited State ◽

Steady State ◽

Fluorescence Spectroscopy ◽

Inclusion Complex ◽

Ground State ◽

Time Resolved Fluorescence ◽

Neutral Form ◽

Time Resolved ◽

Time Resolved Spectroscopy

The photophysical and photoprototropic behaviour of 4-aminobiphenyl (4ABP) in aqueous β-cyclodextrin (β-CDx) solution has been investigated using steady-state and time-resolved fluorescence spectroscopy. Fluorescence of the neutral form of 4ABP is enhanced due to the formation of a 1:1 complex with β-CDx. The formation of this complex has been confirmed by time-resolved spectroscopy. In the presence of β-CDx, no change was observed in the ground state pKa value but the excited state pKa value changed. Based on its photophysical and photoprototropic characteristics in β-CDx, the structure of the 1:1 inclusion complex is proposed.

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Dynamic solvatochromism in solvent mixtures

Pure and Applied Chemistry ◽

10.1351/pac200173030405 ◽

2001 ◽

Vol 73 (3) ◽

pp. 405-409 ◽

Cited By ~ 6

Author(s):

Diana E. Wetzler ◽

Carlos Chesta ◽

Roberto Fernández-Prini ◽

Pedro F. Aramendía

Keyword(s):

Excited State ◽

Ground State ◽

Emission Spectroscopy ◽

Characteristic Time ◽

Polar Solvent ◽

Emission Spectra ◽

Spectral Shift ◽

Solvent Mixtures ◽

Time Resolved ◽

Different Temperatures

Solvatochromism and thermochromism of 4-aminophthalimide and 4-amino-N-methylphthalimide were studied by absorption and steady-state and time-resolved emission spectroscopy in solvent mixtures of tolueneethanol and tolueneacetonitrile at different temperatures. Emission spectra shift to the red upon addition of a polar solvent (PS) to toluene. Solvent mixtures show a much greater thermochromic shift to the blue in emission than the neat solvents. This is explained by the decrease in temperature of the exothermic association of the polar solvent to the excited state. Emission spectra are time dependent in solvent mixtures in the ns timescale. The time evolution of this emission is interpreted on the basis of the different solvation of the ground state and the emitting excited state. SternVolmer plots are obtained for the dependence of the spectral-shift characteristic time with [PS].

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Time-resolved photoluminescence and excited state structure of Bi3+ center in YAlO3

Optical Materials ◽

10.1016/j.optmat.2014.01.030 ◽

2014 ◽

Vol 36 (10) ◽

pp. 1705-1708 ◽

Cited By ~ 13

Author(s):

A. Krasnikov ◽

L. Lipińska ◽

E. Mihokova ◽

M. Nikl ◽

T. Shalapska ◽

...

Keyword(s):

Excited State ◽

State Structure ◽

Time Resolved ◽

Time Resolved Photoluminescence

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Excited-State Dynamics of Room-Temperature Phosphorescent Organic Materials Based on Monobenzil and Bisbenzil Frameworks

Materials ◽

10.3390/ma13173904 ◽

2020 ◽

Vol 13 (17) ◽

pp. 3904

Author(s):

Kaveendra Maduwantha ◽

Shigeyuki Yamada ◽

Kaveenga Rasika Koswattage ◽

Tsutomu Konno ◽

Takuya Hosokai

Keyword(s):

Excited State ◽

Density Functional ◽

Room Temperature ◽

Photophysical Properties ◽

Density Functional Theory Calculations ◽

Time Resolved ◽

Excited State Dynamics ◽

Unique Material ◽

Potential Applications ◽

Time Resolved Photoluminescence

Room-temperature phosphorescent (RTP) materials have been attracting tremendous interest, owing to their unique material characteristics and potential applications for state-of-the-art optoelectronic devices. Recently, we reported the synthesis and fundamental photophysical properties of new RTP materials based on benzil, i.e., fluorinated monobenzil derivative and fluorinated and non-fluorinated bisbenzil derivative analogues [Yamada, S. et al., Beilstein J. Org. Chem. 2020, 16, 1154–1162.]. To deeply understand their RTP properties, we investigated the excited-state dynamics and photostability of the derivatives by means of time-resolved and steady-state photoluminescence spectroscopies. For these derivatives, clear RTP emissions with lifetimes on the microsecond timescale were identified. Among them, the monobenzil derivative was found to be the most efficient RTP material, showing both the longest lifetime and highest amplitude RTP emission. Time-resolved photoluminescence spectra, measured at 77 K, and density functional theory calculations revealed the existence of a second excited triplet state in the vicinity of the first excited singlet state for the monobenzil derivative, indicative of the presence of a fast intersystem crossing pathway. The correlation between the excited state dynamics, emission properties, and conformational flexibility of the three derivatives is discussed.

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Interface charge-transfer induced intralayer excited-state biexcitons in graphene/WS2 van der Waals heterostructures

Nanoscale ◽

10.1039/c9nr02862e ◽

2019 ◽

Vol 11 (28) ◽

pp. 13552-13557 ◽

Cited By ~ 6

Author(s):

Yang Li ◽

Nore Stolte ◽

Baikui Li ◽

Hui Li ◽

Guanghui Cheng ◽

...

Keyword(s):

Excited State ◽

Charge Transfer ◽

Van Der Waals ◽

Exciton Dissociation ◽

Van Der Waals Heterostructures ◽

Interface Charge ◽

Interface Charge Transfer

Highly stable excited-state biexcitons are found in graphene/WS2/BN heterostructures, which is attributed to the charge transfer and exciton dissociation at the hetero-interface.

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