Monte Carlo analysis of frequency domain thermoreflectance data for quantitative measurement of interfacial thermal conductance at solid-liquid interfaces modified with self-assembled monolayers

Abstract A Monte Carlo method, implemented for quantifying confidence bounds on thermoreflectance (TR) measurements of interfacial thermal conductance G at solid-liquid interfaces modified with self-assembled monolayers (SAMs) is presented in this paper. Here we used 1-decanethiol (1DT) and 1H,1H,2H,2H-Perfluorodecanethiol (PFDT) SAMs to achieve two distinct work of adhesion. Using TR measurements in conjunction with Monte Carlo simulations, we determined G values to be 51 ± 7 MWm-2K-1, 58 ± 8 MWm-2K-1, and 72 ± 17 MWm-2K-1 for Au-PFDT-H2O, Au-1DT-H2O, and Au-H2O, respectively. Our results with the new confidence bounds position our experimental data on surfaces modified with SAMs comparable to literature. However, contrary to previous results shown in the literature, our data showed that a significant decrease in G can be seen for DI water on bare Au that was exposed in ambient for extended period. Our results indicate that G could be influenced by factors beyond a simple work of adhesion, an indication also seen from the work of Park et al.. To solidify this finding, further investigation is necessary to better understand G dependence on surface wettability.

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Supramolecular chemistry of helical foldamers at the solid–liquid interface: self-assembled monolayers and anion recognition

Chemical Communications ◽

10.1039/c9cc03851e ◽

2019 ◽

Vol 55 (58) ◽

pp. 8426-8429 ◽

Cited By ~ 5

Author(s):

Catherine Adam ◽

Lara Faour ◽

Valérie Bonnin ◽

Tony Breton ◽

Eric Levillain ◽

...

Keyword(s):

Supramolecular Chemistry ◽

Anion Recognition ◽

Liquid Interface ◽

Self Assembled Monolayers ◽

Guest Binding ◽

Assembled Monolayers ◽

Self Assembled ◽

Solid Liquid Interface ◽

Solid Liquid

Helical foldamers were incorporated in self-assembled monolayers that successfully transduce host–guest binding events.

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Self-assembled monolayers of shape-persistent macrocycles on graphite: interior design and conformational polymorphism

Beilstein Journal of Organic Chemistry ◽

10.3762/bjoc.10.294 ◽

2014 ◽

Vol 10 ◽

pp. 2774-2782 ◽

Cited By ~ 5

Author(s):

Joscha Vollmeyer ◽

Friederike Eberhagen ◽

Sigurd Höger ◽

Stefan-S Jester

Keyword(s):

Interior Design ◽

Pyrolytic Graphite ◽

Self Assembled Monolayers ◽

Scanning Tunneling ◽

Tunneling Microscopy ◽

Conformational Polymorphism ◽

Assembled Monolayers ◽

Self Assembled ◽

Solid Liquid Interface ◽

Solid Liquid

Three shape-persistent naphthylene–phenylene–acetylene macrocycles of identical backbone structures and extraannular substitution patterns but different (empty, apolar, polar) nanopore fillings are self-assembled at the solid/liquid interface of highly oriented pyrolytic graphite and 1,2,4-trichlorobenzene. Submolecularly resolved images of the resulting two-dimensional (2D) crystalline monolayer patterns are obtained by in situ scanning tunneling microscopy. A concentration-dependent conformational polymorphism is found, and open and more dense packing motifs are observed. For all three compounds alike lattice parameters are found, therefore the intermolecular macrocycle distances are mainly determined by their size and symmetry. This is an excellent example that the graphite acts as a template for the macrocycle organization independent from their specific interior.

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Nanobubbles on a Very Flat Hydrophobic Surface Prepared by Self-Assembled Monolayers

ASME 2013 4th International Conference on Micro/Nanoscale Heat and Mass Transfer ◽

10.1115/mnhmt2013-22077 ◽

2013 ◽

Author(s):

Takashi Nishiyama ◽

Koji Takahashi ◽

Yasuyuki Takata

Keyword(s):

Heat Transfer ◽

Gaseous Phase ◽

Hydrophobic Surface ◽

Bubble Nucleation ◽

Liquid Interface ◽

Self Assembled Monolayers ◽

Assembled Monolayers ◽

Self Assembled ◽

Solid Liquid Interface ◽

Solid Liquid

Boiling is one of the most effective heat transfer methods due to its high heat transfer coefficient. Therefore, boiling heat transfer plays a very important role for various applications in many technological and industrial areas. However, a very complex mechanism of boiling, especially bubble nucleation, is still not sufficiently understood. On the other hand, numerous experiments have revealed the existence of soft domains that called nanobubbles at the solid-liquid interface. In this study, to investigate the influence of the solid-liquid interface nanobubbles on the bubble nucleation, an atomic force microscope (AFM) is used to characterize the morphology of nanobubbles. In order to separate the effect of wettability of a solid surface from that of surface structure, a very flat hydrophobic surface was prepared. 1H,1H,2H,2H-Perfluoro-n-octylphosphonic acid (FOPA) formed the interface of hydrophobic self-assembled monolayers (SAMs). As the result of AFM measurement, many nanobubbles about 100 nm in diameter and 30 nm thick are observed at the interface of the FOPA surface and the pure water. In addition, to prove the existence of gaseous phase, the heat conductance measurement by time-domain thermoreflectance method (TDTR) was introduced. TDTR is an ultrafast optical pump probe technique well suited for thermal measurement of thin films. It enables to resolve the thermal conductivity of the thin film and the thermal conductance of the interface. If nanobubbles are the gaseous phase, the big change of interface heat thermal resistance will be seen and the TDTR signal should also change. The effectiveness of a TDTR to confirm the existence of nanobubbles is shown by the model simulation of TDTR. A clear difference is seen in TDTR signal by the existence of only 1 nm gaseous phase. After confirming the existence of nanobubbles by AFM measurement, it can be proved that the nanobubbles are truly gaseous phase of the TDTR measurement.

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