scholarly journals Giant thermal expansion of a two-dimensional supramolecular network triggered by alkyl chain motion

2020 ◽  
Vol 1 (1) ◽  
Author(s):  
Sebastian Scherb ◽  
Antoine Hinaut ◽  
Rémy Pawlak ◽  
J. G. Vilhena ◽  
Yi Liu ◽  
...  
Keyword(s):  
Thermal Expansion ◽  
Alkyl Chain ◽  
Supramolecular Network ◽  
Two Dimensional

Template mediated crystal engineering

1994 ◽  
Vol 52 ◽  
pp. 480-481
Author(s):  
Brigid R. Heywood ◽  
S. Champ
Keyword(s):  
Crystal Engineering ◽  
Electrostatic Interactions ◽  
Alkyl Chain ◽  
Crystallographic Axis ◽  
Two Dimensional ◽  
Engineering Process ◽  
Solution Interface ◽  
Extensive Program ◽  
Geometric Homology ◽  
Long Alkyl Chain

Recent work on the crystallisation of inorganic crystals under compressed monomolecular surfactant films has shown that two dimensional templates can be used to promote the oriented nucleation of solids. When a suitable long alkyl chain surfactant is cast on the crystallisation media a monodispersied population of crystals forms exclusively at the monolayer/solution interface. Each crystal is aligned with a specific crystallographic axis perpendicular to the plane of the monolayer suggesting that nucleation is facilitated by recognition events between the nascent inorganic solid and the organic template.For example, monolayers of the long alkyl chain surfactant, stearic acid will promote the oriented nucleation of the calcium carbonate polymorph, calcite, on the (100) face, whereas compressed monolayers of n-eicosyl sulphate will induce calcite nucleation on the (001) face, (Figure 1 & 2). An extensive program of research has confirmed the general principle that molecular recognition events at the interface (including electrostatic interactions, geometric homology, stereochemical complementarity) can be used to promote the crystal engineering process.

Magnetoelastic coupling, negative thermal expansion, and two-dimensional magnetic excitations in FeAs

2021 ◽  
Vol 103 (9) ◽  
Author(s):  
J. L. Niedziela ◽  
L. D. Sanjeewa ◽  
A. A. Podlesnyak ◽  
L. DeBeer-Schmitt ◽  
S. J. Kuhn ◽  
...  
Keyword(s):  
Thermal Expansion ◽  
Negative Thermal Expansion ◽  
Two Dimensional ◽  
Magnetic Excitations ◽  
Magnetoelastic Coupling

Thermally boosted upconversion and downshifting luminescence in Sc2(MoO4)3:Yb/Er with two-dimensional negative thermal expansion

2021 ◽  
Author(s):  
Jinsheng Liao ◽  
Minghua Wang ◽  
Fulin Lin ◽  
Zhuo Han ◽  
Datao Tu ◽  
...  
Keyword(s):  
Thermal Expansion ◽  
Near Infrared ◽  
Negative Thermal Expansion ◽  
Thermal Quenching ◽  
Relative Sensitivity ◽  
Strong Temperature Dependence ◽  
Two Dimensional ◽  
X Ray Diffraction ◽  
Higher Temperature

Abstract Lanthanide (Ln3+)-doped phosphors generally suffer from thermal quenching, in which their photoluminescence (PL) intensities decrease at the higher temperature. Herein, we report a class of unique two-dimensional negative-thermal-expansion phosphor of Sc2(MoO4)3:Yb/Er. By virtue of the reduced distances between sensitizers and emitters as well as confined energy migration with increasing the temperature, a 45-fold enhancement of green upconversion (UC) luminescence and a 450-fold enhancement of near-infrared downshifting (DS) luminescence of Er3+ are achieved from 25 to 500 ˚C. The thermally boosted UC and DS luminescence mechanism is systematically investigated through in situ temperature-dependent Raman spectroscopy, synchrotron X-ray diffraction and PL dynamics. Moreover, the luminescence lifetime of 4I11/2 of Er3+ in Sc2(MoO4)3:Yb/Er displays a strong temperature dependence, enabling ratiometric thermometry with the highest relative sensitivity of 13.4%/K at 298 K. These findings may gain a vital insight into the design of negative-thermal-expansion Ln3+-doped phosphors for versatile applications.

scholarly journals First-principles study on the electrical and thermal properties of the semiconducting Sc3(CN)F2 MXene

RSC Advances ◽  
2018 ◽  
Vol 8 (40) ◽  
pp. 22452-22459 ◽  
Author(s):  
Kan Luo ◽  
Xian-Hu Zha ◽  
Yuhong Zhou ◽  
Zhansheng Guo ◽  
Cheng-Te Lin ◽  
...  
Keyword(s):  
Thermal Expansion ◽  
Thermal Properties ◽  
Dft Calculations ◽  
Specific Heat ◽  
Thermal Expansion Coefficient ◽  
First Principles ◽  
Two Dimensional ◽  
Nanoelectronic Devices ◽  
Low Thermal Expansion ◽  
High Carrier

The two-dimensional semiconducting Sc3(CN)F2 MXene presents relatively high carrier mobilities, specific heat and low thermal expansion coefficient from DFT calculations, and produces a good application prospect for nanoelectronic devices.

scholarly journals A facile synthetic route to tungsten diselenide using a new precursor containing a long alkyl chain cation for multifunctional electronic and optoelectronic applications

RSC Advances ◽  
2019 ◽  
Vol 9 (11) ◽  
pp. 6169-6176
Author(s):  
Jahee Kim ◽  
Yi Rang Lim ◽  
Yeoheung Yoon ◽  
Wooseok Song ◽  
Bo Keun Park ◽  
...  
Keyword(s):  
Large Scale ◽  
Alkyl Chain ◽  
Low Cost ◽  
Transition Metal Dichalcogenides ◽  
Two Dimensional ◽  
Single Source ◽  
Synthetic Route ◽  
Decomposition Processes ◽  
Metal Dichalcogenides ◽  
Long Alkyl Chain

Single source precursors for coating and subsequent thermal decomposition processes enable a large-scale, low-cost synthesis of two-dimensional transition metal dichalcogenides (TMDs).

Two new CdII MOFs of 1,4-bis(1H-benzimidazol-1-yl)butane and flexible dicarboxylate ligands: luminescence sensing towards Fe3+

2020 ◽  
Vol 76 (11) ◽  
pp. 1024-1033
Author(s):  
Fang-Hua Zhao ◽  
Shi-Yao Li ◽  
Wen-Yu Guo ◽  
Zi-Hao Zhao ◽  
Xiao-Wen Guo ◽  
...  
Keyword(s):  
Aqueous Solution ◽  
Solid State ◽  
Hydrogen Bonds ◽  
Layer Structure ◽  
Three Dimensional ◽  
Supramolecular Network ◽  
Two Dimensional ◽  
X Ray Diffraction ◽  
X Ray ◽  
Vis Spectroscopy

Two new CdII MOFs, namely, two-dimensional (2D) poly[[[μ2-1,4-bis(1H-benzimidazol-1-yl)butane](μ2-heptanedioato)cadmium(II)] tetrahydrate], {[Cd(C7H10O4)(C18H18N4)]·4H2O} n or {[Cd(Pim)(bbimb)]·4H2O} n (1), and 2D poly[diaqua[μ2-1,4-bis(1H-benzimidazol-1-yl)butane](μ4-decanedioato)(μ2-decanedioato)dicadmium(II)], [Cd2(C10H16O4)2(C18H18N4)(H2O)2] n or [Cd(Seb)(bbimb)0.5(H2O)] n (2), have been synthesized hydrothermally based on the 1,4-bis(1H-benzimidazol-1-yl)butane (bbimb) and pimelate (Pim2−, heptanedioate) or sebacate (Seb2−, decanedioate) ligands. Both MOFs were structurally characterized by single-crystal X-ray diffraction. In 1, the CdII centres are connected by bbimb and Pim2− ligands to generate a 2D sql layer structure with an octameric (H2O)8 water cluster. The 2D layers are further connected by O—H...O hydrogen bonds, resulting in a three-dimensional (3D) supramolecular structure. In 2, the CdII centres are coordinated by Seb2− ligands to form binuclear Cd2 units which are linked by bbimb and Seb2− ligands into a 2D hxl layer. The 2D layers are further connected by O—H...O hydrogen bonds, leading to an 8-connected 3D hex supramolecular network. IR and UV–Vis spectroscopy, thermogravimetric analysis and solid-state photoluminescence analysis were carried out on both MOFs. Luminescence sensing experiments reveal that both MOFs have good selective sensing towards Fe3+ in aqueous solution.

Sign in / Sign up

Export Citation Format

Share Document