Polycyclic aromatic hydrocarbons (PAHs) are excellent building blocks for the creation of two-dimensional (2D) nanosheets.However,large PAHs tend to exhibit poor or no solubility in organic solvents and water.T oo vercome this issue,w ee mployed water-soluble micellar capsules consisting of V-shaped amphiphilic molecules.C haracteristic electrochemical behavior was observed in 0.1m H 2 SO 4 in the presence of the water-soluble capsules containing PAHs,s uch as ovalene,c ircobiphenyl, and dicoronylene.F urthermore, under these conditions,P AHs were released from the capsules, resulting in the formation of a2 Da dlayer of PAHs at the electrochemical interface.F inally,u sing electrochemical scanning tunneling microscopy, we demonstrate that our molecular containers based on water-soluble molecular capsules allowthe facile preparation of 2D PAHa dlayers in addition to structurally controlling nanostructure formation on Au surfaces.Carbon materials,s uch as graphene,h ave been extensively studied for their application in electronic devices, [1][2][3] photodetectors, [4][5][6] capacitors, [7] electrocatalysis, [8][9][10] and sensors. [11] Similarly,p olycyclic aromatic hydrocarbons (PAHs) with planar structures exhibit excellent donor abilities owing to their p-conjugated structures.A ss uch, PA Hs are promising materials for use as two-dimensional (2D) nanoarchitectures, such as "nanographene", which should create novel functionalities for electronic devices,i ncluding electrochromic devices [1,12] and quantum dots. [13] Fore xample,f unctionalized graphene quantum dots that allow the control of band gaps indicate the structural dependence of photocatalysts in water splitting and carbon dioxide reduction under visible-light irradiation. [13] Indeed, to date,anumber of attractive PA Hs have been synthesized by the Müllen group. [1, 12,14] Thedesign and synthesis of structurally defined PA Hs are essential for the creation of functional graphenes based on elemental doping and periodical defects (or vacancies) as the building blocks.However,large PA Hs without peripheral substituents are insoluble in both water and organic solvents.T he formation of adlayers on electrode surfaces is challenging because PA Hs without peripheral substituents are used as 2D molecular templates, [15] have applications in conductance enhancement between nanographene and Au junctions, [16] and are used in organic field-effect transistors (OFETs). [17] In contrast, the V-shaped amphiphilic molecule 1 (Scheme 1) forms micellar capsules (1) n in water and solubilizes various water-insoluble compounds.I np articular, p-conjugated planar molecules,s uch as metalloporphyrins,p hthalocyanines,p entacenes,a nd coronenes,h ave been applied for this purpose. [18,19] We report herein water-soluble molecular capsules consisting of V-shaped amphiphilic molecules for the uptake of large PA Hs (i.e., ovalene,c ircobiphenyl, and dicoronylene; Scheme 1). In this study,w ea lso examined the electrochemical behavior of the PA H-containing molecular capsules an...

Electrochemical detection of ethylenebis(dithiocarbamic acid) manganese zinc complex (Manzeb), a widely used insecticide, by reductive desorption from Au(111) and Au(100) has been studied. Dithiocarbamate groups containing adlayer were formed on gold single-crystal electrodes by immersing into a Manzeb aqueous solution. The electrochemical responses and the adsorption amounts were evaluated based on the reductive desorption of sulfur species from the gold surface in alkaline solution. The detection limit for Manzeb depended on the modification time and the crystallographic orientation of gold. The limits of detection were 500 nM and 100 nM when a Au(111) electrode and a Au(100) electrode were used, respectively. The surface-enhanced infrared absorption spectra of Manzeb on a Au thin film electrode in its monolayer state showed that Manzeb was adsorbed on the substrate via the dithiocarbamate moiety and the long axis of ethylenebis(dithiocarbamate) dianion was almost perpendicular to the surface.

Polycyclic aromatic hydrocarbons (PAHs) are excellent building blocks for the creation of two‐dimensional (2D) nanosheets. However, large PAHs tend to exhibit poor or no solubility in organic solvents and water. To overcome this issue, we employed water‐soluble micellar capsules consisting of V‐shaped amphiphilic molecules. Characteristic electrochemical behavior was observed in 0.1 m H2SO4 in the presence of the water‐soluble capsules containing PAHs, such as ovalene, circobiphenyl, and dicoronylene. Furthermore, under these conditions, PAHs were released from the capsules, resulting in the formation of a 2D adlayer of PAHs at the electrochemical interface. Finally, using electrochemical scanning tunneling microscopy, we demonstrate that our molecular containers based on water‐soluble molecular capsules allow the facile preparation of 2D PAH adlayers in addition to structurally controlling nanostructure formation on Au surfaces.

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Carbon materials such as graphene have been extensively studied for their application in electronic devices,electrocatalysis, and sensors. In contrast, polycyclic aromatic hydrocarbons (PAHs), the so-called nanographenes, are excellent materials for the creation of two-dimensional (2D) nanosheets.[1] The formation of adlayers on electrode surfaces is challenging because PAHs without peripheral substituents are used as 2D molecular templates and applications in conductance enhancement and organic field-effect transistors.[2] However, large PAHs tend to exhibit poor or no solubilities in organic solvents and water. To overcome this issue, in this study, we employed water-soluble micellar capsules consisting of V-shaped amphiphilic molecules. Characteristic electrochemical behaviors were observed in 0.1 M H2SO4 in the presence of the water-soluble capsules containing PAHs such as dicoronylene. Furthermore, under these conditions, PAHs were released from the capsules, resulting in the formation of a 2D adlayer of PAHs at the electrochemical interface. Finally, using electrochemical scanning tunneling microscopy (EC-STM), we demonstrate that our molecular containers based on the water-soluble molecular capsules allow the facile preparation of 2D PAH adlayers in addition to structurally controlling nanostructure formation on Au surfaces.In particular, dicoronylene molecules formed a highly ordered adlayer with c(4 x 8√3)rect adlattice.[3] References: [1] J. Wu, W. Pisula, K. Müllen, Chem. Rev. 2007, 107, 718. [2] L. Zhang, Y. Cao, N. S. Colella, Y. Liang, J.-L. Brédas, K. N. Houk, A. L. Briseno, Acc. Chem. Res. 2015, 48, 500. [3] S. Origuchi, M. Kishimoto, M. Yoshizawa, S. Yoshimoto, Angew. Chem., Int. Ed. 2018, 57, 15481.