Scanning tunneling microscopy studies of self assembled nanostructures on graphite

... Introduction Several studies of metals on graphite have demonstrated the fabrication of different types of nanostructures and behavior of metal atoms on graphite Ganz et al studied the growth of different ... interaction can alter particle shape significantly 1.1 Nucleation and Growth of nanostructures on Inert substrates The understanding of nucleation and growth of self- assembled nanostructures on solid ... characterize self- assembled nanostructures for fundamental interests along with several applications in the field of nanodevices [1113] The shape, size and location of self- assembled nanostructures...

Studies of self assembled monolayers on highly oriented pyrolytic graphite using scanning tunneling microscopy and computational simulation 1

... concept of the self- assembled monolayers (SAMs) is primarily introduced by Zisman in 19 46 [12 , 13 ] The traditional SAMs is an organized layer of INTRODUCTION amphiphilic molecules in which one ... development, and biological process Works of thiols adsorbed on gold surfaces by Nuzzo and Allara [13 , 15 ] in the early 19 80s and trichlorosilanes on silicon oxide by Maoz and Sagiv [13 , 16 ] introduced ... deposited onto the substrate surface from either vapor or liquid phase A typical example is that the formation of thiolate monolayers on the gold (11 1) surface (Fig 1. 3) Fig 1. 3 Schematic of an n-dodecanethiolate...

Studies of self assembled monolayers on highly oriented pyrolytic graphite using scanning tunneling microscopy and computational simulation 2

... Valiyaveettil Suresh’s group C12H25 C12H25 C12H25 N C12H25 C12H25 C12H25 N C12H25 C12H25 C12H25 C12H25 CPAH CHBC C12H25 Br N Br N C12H25 C12H25 C12H25 CHBC2 N C12H25 N C12H25 TCC 34 EXPERIMENTAL R ... C12H25 C12H25 N C12H25 C12H25 N C12H25 C12H25 CHBC3 Derivatives of perylene by Prof Valiyaveettil Suresh’s group C12H25 N O O O C12H25 N O O C12H25 N O S Br Br S O N O C12H25 O O DDPER N O C12H25 S170 ... C12H25 C12H25 N O O C12H25 N O OMe OMe MeO OMe MeO MeO OMe OMe O N O C12H25 S169 O N O C12H25 S1 72 36 EXPERIMENTAL O C12H25 N O O C12H25 N O OCH3 OCH3 H3CO S S H3CO OCH3 OCH3 O N O C12H25 SIV233...

Studies of self assembled monolayers on highly oriented pyrolytic graphite using scanning tunneling microscopy and computational simulation 3

... calibration of the “A” scanner for scanning tunneling microscope function 3. 3.2 Calibration Procedures The calibration of STM can be conducted with a standard sample: highly ordered pyrolytic graphite ... bright carbon atoms was 0.267nm 44 CALIBRATION Fig 3. 4 Section Analysis of the STM image in Fig 3. 3 along the orientation of the white arrow Fig 3. 5 shows the standard parameters of the graphite ... finds useful applications such as the production and detection of sound, generation of high voltages, electronic frequency generation, microbalance, and ultra fine focusing of optical assemblies...

Studies of self assembled monolayers on highly oriented pyrolytic graphite using scanning tunneling microscopy and computational simulation 4

... to verify the existence of interaction between the adsorbate and graphite surface 4. 2 STM Results and Computational Simulations 4. 2.1 Solution Preparation Three solutions of fatty acids in phenyloctane ... interaction as shown in Table 4. 2 Our computational simulation does not reveal the physisorption route and steps of the monolayers formation, instead, it can only provide the energies of the final ... about the configuration of two species within the 63 PHYSISORPTION OF BINARY FATTY ACIDS ON HOPG monolayers formed by the binary acids solution Fig 4. 9 Top view of Model A and B with graphite lattice...

Studies of self assembled monolayers on highly oriented pyrolytic graphite using scanning tunneling microscopy and computational simulation 5

... steric repulsion Fig 5. 4 The molecular model of the DDPER arrays 5. 4 The Computational Simulation 5. 4.1 Conformation of gas phase DDPER and its derivatives Building of the computational model started ... interaction 83 FORMATION OF SAMs CONRTOLLED BY STERIC EFFECTS 5. 4.2 DDPER/HOPG vs S170/HOPG Computational simulation was applied to compare the adsorption energies of DDPER and S170 on graphite ... Section analysis showed that the DDPER centers had an average relative height of 0.2 nm (Fig 5. 3) Fig 5. 3 The height profile of the DDPER Self- Assembled Monolayers 78 FORMATION OF SAMs CONRTOLLED...

Studies of self assembled monolayers on highly oriented pyrolytic graphite using scanning tunneling microscopy and computational simulation 6

... 3.900.80nm and 2.950 .60 nm N N N Fig 6. 4 Left: High resolution image of HHB monolayers: Bright hexagons represent the benzene ring of HHB Right: the molecular configuration of HHB (R-HHB) in monolayers ... N Fig 6. 3 Left: High resolution image of HHB monolayers: Bright hexagons represent the benzene ring of HHB Right: the molecular configuration of HHB (L-HHB) in monolayers (Vbias = 100mV, and Iset ... Fig 6. 8 Illustration of physisorption of HHB molecule onto HOPG surfaces 102 ADSORPTION-INDUCED CHIRAL SAMs The physisorption process can be considered as an addition reaction between the HHB and...

Studies of self assembled monolayers on highly oriented pyrolytic graphite using scanning tunneling microscopy and computational simulation 7

... be 7. 4.1 Concentration It is very obvious that the possibility of forming SAMs on HOPG is highly concentration dependent   1 k [ P] When the concentration of the molecule increases, (7- 7) ... observation and equation (7- 10), a rough diagram [Fig 7. 4] of the surface coverage  vs [P] was proposed 1 17 FORMATION OF 2D CRYSTALS ON HOPG Fig 7. 4 Propsed diagram of surface coverage  vs solution ... growth of SAMs on HOPG Although the graphite surface has a high degree of perfection, they still have steps and defects, as shown in Fig 7. 1 112 FORMATION OF 2D CRYSTALS ON HOPG Fig 7. 1 STM image of...

morphology change of self-assembled zno 3d nanostructures with different ph

... and Physics 113 (2009) 389–394 391 Fig FE-SEM images of the ZnO 3D nanostructures synthesized at different pH: (a) pH 9.0; (b) pH 9.5; (c) pH 10.0; (d) pH 10.5; (e) pH 11.0; (f) pH 11.5; (g) pH ... Room-temperature photoluminescence spectra from the ZnO 3D nanostructures grown in solutions of different pH ( ex = 266 nm) quality of self-assembled ZnO 3D nanostructure were obtained at pH 10.5 This ... increased with increasing pH in the lower pH range, showing a maximum value at pH 10.5–11.0, and decreased at pH 11.5 As shown in Fig 2, the morphology of the ZnO nanostructures synthesized from the pH...

Two dimensional molecular self assemblies on surfaces studied by low temperature scanning tunneling microscopy

... controls the molecular switching …………………………………………… 148 ⅹⅶ LIST OF ABBREVIATIONS 2D LT-STM Two- Dimensional Low Temperature Scanning Tunneling Microscopy STS Scanning Tunneling Spectroscopy MBE Molecular ... Field Ion Microscopy AFM Atomic Force Microscope SEM Scanning Electron Microscopy TEM Transmission Electron Microscopy NFSOM Near-Field Scanning Optical Microscopy LEEM Low- Energy Electron Microscopy ... are demonstrated by low- temperature scanning tunneling microscopy (LT-STM) in ultra-high vacuum (UHV) environments Intensive effort is devoted to construct mono- and bi-component organic molecular...

STM investigations of self assembled bismuth nanostructures and ultra fine gold nanparticles

... STM INVESTIGATIONS OF SELF- ASSEMBLED BISMUTH NANOSTRUCTURES AND ULTRA- FINE GOLD NANOPARTICLES CHU XINJUN (M Tech., Peking Univ Tech.) A THESIS SUBMITTED FOR THE DEGREE OF DOCTOR OF PHILOSOPHY ... High-resolution STM image (16 nm× nm) of an ultra- thin Bi NW with 16 PTCDA molecules on top The inset shows a 3-D view of part of this NW (b) Schematic diagram of growth of Bi(110) NWs (c) A STM line profile ... overview of motivation and synopsis of this PHD project, and a general introduction of surfaces/interfaces, thin film growth and self- assembly in nanoscience 1.1 Motivation and Synopsis Bismuth...

STRUCTURES OF ADSORBED HALIDE ANIONS ON a COPPER ELECTRODE STUDIED BY IN SITU SCANNING TUNNELING MICROSCOPY

... electrode For the adsorption of iodide anions on the same substrate surface the supporting electrolyte (10 mM HCl) was replaced by STRUCTURES OF ADSORBED HALIDE ANIONS ON A COPPER ELECTRODE STUDIED ... IV CONCLUSION The electrochemical behaviors of a Cu(100) electrode in pure dilute HCl and iodide containing HCl solutions was investigated by in situ STM Halide anions adsorb with typical structures ... solely commensurate along the STRUCTURES OF ADSORBED HALIDE ANIONS ON A COPPER ELECTRODE STUDIED BY 243 Fig Morphologic feature of a chloride adlayer on a Cu(100) electrode surface, 83.23 nm ×...

Morphology and growth mechanism study of self assembled silicon nanowires synthesized by thermal evaporation

... [10±13] and thermal evaporation [14±17] are two methods normally used for the synthesis of SiNWs The key point in these two methods is the formation of a sucient amount of silicon atoms and/ or silicon ... made of a Si core and a SiO2 sheath The one-dimensional growth of SiNWs is facilitated by the SiO2 sheath that con®nes the lateral growth of SiNWs, and the high absorptivity for Si±O clusters of ... related to the morphology and growth temperature We show that the formation of SiNWs is indeed closely related to the amorphous SiO particles, and the growth and self- assembling process of SiNWs on...

hydrothermal synthesis and characterization of self - assembled h - wo3

... sharp diffraction peaks (Fig 1a) are observed, indicative of high-degree crystallinity On the other hand, the as-synthesized h- WO3 with the NH4 + -based EDTA sample showed broader peaks with ... urchin-like (NH4 + -based EDTA) and (c) JCPDS card # 3 3-1 387, hydrothermally synthesized at 180 ◦ C for h solutions are shown in Fig For the as-synthesized h- WO3 with Na+ -based EDTA, intense and ... bundles and urchin-like structure crystalline hWO3 samples were synthesized through hydrothermal reaction of Na2 WO4 · 2H2 O, HCl and Na+ - or NH4 + -based EDTA salt solutions in the presence of Na2...

Báo cáo hóa học: " Thermal conductivity and viscosity of self-assembled alcohol/polyalphaolefin nanoemulsion fluids" ppt

... the thermal conductivity of liquids [12,35] Most of published thermal conductivity data on the nanofluids were obtained using the hot-wire Figure Alcohol/PAO nanoemulsion fluids (Bottle A) and ... Kang YT, Chen G: Thermal conductivity and viscosity of water-in-oil nanoemulsions Colloids Surf A Physicochem Eng Aspects 2008, 326:67-72 18 Tzou DY: Thermal instability of nanofluids in natural ... the effects of the dispersed droplets on thermal conductivity and viscosity Alcohol and PAO have similar thermal conductivity values at room temperature and are physically immiscible SANS measurements...

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Từ khóa: visualization of the atomic scale structure and reactivity of metal carbide surfaces using scanning tunneling microscopy scanning tunneling microscopy of carbon nanotubes and nanocones epitaxial growth and electronic structure of self assembled quantum dots electrical characterization of self assembled monolayers use of self assembled surfactants for nanomaterials synthesis evaluation of self help declarations on may 6 alsten j g 1999 self assembled monolayers on engineering metals structure derivatization and utility langmuir 15 7605 7614 comparative studies of scanning electron microscopy and transmission electron microscopy differential scanning calorimetry studies of phospholipid membranes the interdigitated gel phas scanning electron microscopy of bone synthesis of genetically engineered protein polymers recombinamers as an example of advanced self assembled smart materials design of soft nanostructures and increased complexity of self assembly by perfluorinated segments 11fundamental principles of scanning electron microscopy self assembled films of latex particles collective optical properties of particles self assembled in multilayers Báo cáo thực tập tại nhà thuốc tại Thành phố Hồ Chí Minh năm 2018 Nghiên cứu sự biến đổi một số cytokin ở bệnh nhân xơ cứng bì hệ thống Nghiên cứu tổ hợp chất chỉ điểm sinh học vWF, VCAM 1, MCP 1, d dimer trong chẩn đoán và tiên lượng nhồi máu não cấp Một số giải pháp nâng cao chất lượng streaming thích ứng video trên nền giao thức HTTP Giáo án Sinh học 11 bài 13: Thực hành phát hiện diệp lục và carôtenôit Giáo án Sinh học 11 bài 13: Thực hành phát hiện diệp lục và carôtenôit Quản lý hoạt động học tập của học sinh theo hướng phát triển kỹ năng học tập hợp tác tại các trường phổ thông dân tộc bán trú huyện ba chẽ, tỉnh quảng ninh Nghiên cứu về mô hình thống kê học sâu và ứng dụng trong nhận dạng chữ viết tay hạn chế Nghiên cứu khả năng đo năng lượng điện bằng hệ thu thập dữ liệu 16 kênh DEWE 5000 Tìm hiểu công cụ đánh giá hệ thống đảm bảo an toàn hệ thống thông tin Sở hữu ruộng đất và kinh tế nông nghiệp châu ôn (lạng sơn) nửa đầu thế kỷ XIX Chuong 2 nhận dạng rui ro Tổ chức và hoạt động của Phòng Tư pháp từ thực tiễn tỉnh Phú Thọ (Luận văn thạc sĩ)BT Tieng anh 6 UNIT 2 Tranh tụng tại phiên tòa hình sự sơ thẩm theo pháp luật tố tụng hình sự Việt Nam từ thực tiễn xét xử của các Tòa án quân sự Quân khu (Luận văn thạc sĩ)Giáo án Sinh học 11 bài 15: Tiêu hóa ở động vật Giáo án Sinh học 11 bài 15: Tiêu hóa ở động vật Nguyên tắc phân hóa trách nhiệm hình sự đối với người dưới 18 tuổi phạm tội trong pháp luật hình sự Việt Nam (Luận văn thạc sĩ)Giáo án Sinh học 11 bài 14: Thực hành phát hiện hô hấp ở thực vật Đổi mới quản lý tài chính trong hoạt động khoa học xã hội trường hợp viện hàn lâm khoa học xã hội việt nam