1
|
Marks J, Wang J, Sun BJ, McAnally M, Turner AM, Chang AHH, Kaiser RI. Thermal Synthesis of Carbamic Acid and Its Dimer in Interstellar Ices: A Reservoir of Interstellar Amino Acids. ACS CENTRAL SCIENCE 2023; 9:2241-2250. [PMID: 38161363 PMCID: PMC10755733 DOI: 10.1021/acscentsci.3c01108] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 09/01/2023] [Revised: 10/13/2023] [Accepted: 10/19/2023] [Indexed: 01/03/2024]
Abstract
Reactions in interstellar ices are shown to be capable of producing key prebiotic molecules without energetic radiation that are necessary for the origins of life. When present in interstellar ices, carbamic acid (H2NCOOH) can serve as a condensed-phase source of the molecular building blocks for more complex proteinogenic amino acids. Here, Fourier transform infrared spectroscopy during heating of analogue interstellar ices composed of carbon dioxide and ammonia identifies the lower limit for thermal synthesis to be 62 ± 3 K for carbamic acid and 39 ± 4 K for its salt ammonium carbamate ([H2NCOO-][NH4+]). While solvation increases the rates of formation and decomposition of carbamic acid in ice, the absence of solvent effects after sublimation results in a significant barrier to dissociation and a stable gas-phase molecule. Photoionization reflectron time-of-flight mass spectrometry permits an unprecedented degree of sensitivity toward gaseous carbamic acid and demonstrates sublimation of carbamic acid from decomposition of ammonium carbamate and again at higher temperatures from carbamic acid dimers. Since the dimer is observed at temperatures up to 290 K, similar to the environment of a protoplanetary disk, this dimer is a promising reservoir of amino acids during the formation of stars and planets.
Collapse
Affiliation(s)
- Joshua
H. Marks
- W.
M. Keck Research Laboratory in Astrochemistry, University of Hawai’i at Manoa, Honolulu, Hawaii 96822, United States
- Department
of Chemistry, University of Hawai’i
at Manoa, Honolulu, Hawaii 96822, United States
| | - Jia Wang
- W.
M. Keck Research Laboratory in Astrochemistry, University of Hawai’i at Manoa, Honolulu, Hawaii 96822, United States
- Department
of Chemistry, University of Hawai’i
at Manoa, Honolulu, Hawaii 96822, United States
| | - Bing-Jian Sun
- Department
of Chemistry, National Dong Hwa University, Hualien 974, Taiwan
| | - Mason McAnally
- W.
M. Keck Research Laboratory in Astrochemistry, University of Hawai’i at Manoa, Honolulu, Hawaii 96822, United States
- Department
of Chemistry, University of Hawai’i
at Manoa, Honolulu, Hawaii 96822, United States
| | - Andrew M. Turner
- W.
M. Keck Research Laboratory in Astrochemistry, University of Hawai’i at Manoa, Honolulu, Hawaii 96822, United States
- Department
of Chemistry, University of Hawai’i
at Manoa, Honolulu, Hawaii 96822, United States
| | - Agnes H.-H. Chang
- Department
of Chemistry, National Dong Hwa University, Hualien 974, Taiwan
| | - Ralf I. Kaiser
- W.
M. Keck Research Laboratory in Astrochemistry, University of Hawai’i at Manoa, Honolulu, Hawaii 96822, United States
- Department
of Chemistry, University of Hawai’i
at Manoa, Honolulu, Hawaii 96822, United States
| |
Collapse
|
2
|
Fallica R, Nannarone S, Mahne N, Malvezzi AM, Berti A, Simone DD. Evolution of Secondary Electrons Emission During EUV Exposure in Photoresists. J PHOTOPOLYM SCI TEC 2021. [DOI: 10.2494/photopolymer.34.99] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
|
3
|
Zheng Y, Hoffman A, Huang K. Atomistic Insight into Nitrogen-Terminated Diamond(001) Surfaces by the Adsorption of N, NH, and NH 2: A Density Functional Theory Study. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2021; 37:6248-6256. [PMID: 33974432 DOI: 10.1021/acs.langmuir.1c00577] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/12/2023]
Abstract
Layer-by-layer construction of diamond devices for spin-sensing calls for the atomistic understanding of the nitrogen species on diamond surfaces. Motivated by recent experiments, we used density functional theory simulations to examine the adsorption of nitrogen species (N, NH, and NH2) on bare and hydrogenated diamond(001) surfaces. On the bare substrate, we find that nitrogen species favor to attack the C═C dimers at low coverages, forming N(ad) and NH(ad) in a bridge configuration and NH2(ad) in a terminal configuration. At increasing coverages up to one full monolayer, the computed adsorption geometries and energetics suggest that the adsorbate-adsorbate interactions are attractive for N(ad), but repulsive for NH(ad) and NH2(ad). On the hydrogenated substrate, the adsorbed nitrogen species are subject to structural modification, as resulted from the weakened adsorbate-substrate interactions. Further, we calculated the vibration of nitrogen species and the 1s core-level shift of surface carbons, providing atomistic insights into the nature of surface bonding. Lastly, we simulated images of representative nitrogen species adsorbed on diamond(001), guiding future work using scanning tunneling microscopy.
Collapse
Affiliation(s)
- Yusen Zheng
- Chemistry Program, Guangdong Technion Israel Institute of Technology, 241 Daxue Road, Shantou, Guangdong Province 515603, China
- Schulich Faculty of Chemistry, Technion-Israel Institute of Technology, Haifa 32000, Israel
| | - Alon Hoffman
- Schulich Faculty of Chemistry, Technion-Israel Institute of Technology, Haifa 32000, Israel
| | - Kai Huang
- Chemistry Program, Guangdong Technion Israel Institute of Technology, 241 Daxue Road, Shantou, Guangdong Province 515603, China
| |
Collapse
|
4
|
James RL, Ioppolo S, Hoffmann SV, Jones NC, Mason NJ, Dawes A. Systematic investigation of CO 2 : NH 3 ice mixtures using mid-IR and VUV spectroscopy – part 2: electron irradiation and thermal processing. RSC Adv 2021; 11:33055-33069. [PMID: 35493573 PMCID: PMC9042239 DOI: 10.1039/d1ra05600j] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/21/2021] [Accepted: 09/20/2021] [Indexed: 11/21/2022] Open
Abstract
Many experimental parameters determine the chemical and physical properties of interstellar ice analogues, each of which may influence the molecular synthesis that occurs in such ices. In part 1, James et al., RSC Adv., 2020, 10, 37517, we demonstrated the effects that the stoichiometric mixing ratio had on the chemical and physical properties of CO2 : NH3 mixtures and the impact on molecular synthesis induced by thermal processing. Here, in part 2, we extend this to include 1 keV electron irradiation at 20 K of several stoichiometric mixing ratios of CO2 : NH3 ices followed by thermal processing. We demonstrate that not all stoichiometric mixing ratios of CO2 : NH3 ice form the same products. Not only did the 4 : 1 ratio form a different residue after thermal processing, but O3 was observed after electron irradiation at 20 K, which was not observed in the other ratios. For the other ratios, the residue formed from a thermal reaction similar to the work shown in Part 1. However, conversion of ammonium carbamate to carbamic acid was hindered due to electron irradiation at 20 K. Our results demonstrate the need to systematically investigate stoichiometric mixing ratios to better characterise the chemical and physical properties of interstellar ice analogues to further our understanding of the routes of molecular synthesis under different astrochemical conditions. The stoichiometric mixing ratio of CO2 : NH3 ice mixtures determines the electron irradiation products at 20 K and the composition of residue material formed after thermal processing.![]()
Collapse
Affiliation(s)
- Rachel L. James
- School of Physical Sciences, The Open University, Walton Hall, Milton Keynes, UK
| | - Sergio Ioppolo
- School of Electronic Engineering and Computer Science, Queen Mary University of London, Mile End Road, London, UK
| | - Søren V. Hoffmann
- ISA, Department of Physics and Astronomy, Aarhus University, Ny Munkegade 120, DK-8000 Aarhus C, Denmark
| | - Nykola C. Jones
- ISA, Department of Physics and Astronomy, Aarhus University, Ny Munkegade 120, DK-8000 Aarhus C, Denmark
| | - Nigel J. Mason
- School of Physical Sciences, University of Kent, Canterbury, Kent, UK
| | - Anita Dawes
- School of Physical Sciences, The Open University, Walton Hall, Milton Keynes, UK
| |
Collapse
|
5
|
James RL, Ioppolo S, Hoffmann SV, Jones NC, Mason NJ, Dawes A. Systematic investigation of CO 2 : NH 3 ice mixtures using mid-IR and VUV spectroscopy - part 1: thermal processing. RSC Adv 2020; 10:37515-37528. [PMID: 35521284 PMCID: PMC9057146 DOI: 10.1039/d0ra05826b] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/03/2020] [Accepted: 09/25/2020] [Indexed: 12/24/2022] Open
Abstract
The adjustment of experimental parameters in interstellar ice analogues can have profound effects on molecular synthesis within an ice system. We demonstrated this by systematically investigating the stoichiometric mixing ratios of CO2 : NH3 ices as a function of thermal processing using mid-IR and VUV spectroscopy. We observed that the type of CO2 bonding environment was dependent on the different stoichiometric mixing ratios and that this pre-determined the NH3 crystallite structure after phase change. The thermal reactivity of the ices was linked to the different chemical and physical properties of the stoichiometric ratios. Our results provide new details into the chemical and physical properties of the different stoichiometric CO2 : NH3 ices enhancing our understanding of the thermally induced molecular synthesis within this ice system.
Collapse
Affiliation(s)
- Rachel L James
- School of Physical Sciences, The Open University Walton Hall Milton Keynes UK +44 (0)1908 654192 +44 (0)1908 332012
| | - Sergio Ioppolo
- School of Electronic Engineering and Computer Science, Queen Mary University of London Mile End Road London UK
| | - Søren V Hoffmann
- ISA, Department of Physics and Astronomy, Aarhus University Ny Munkegade 120 DK-8000 Aarhus C Denmark
| | - Nykola C Jones
- ISA, Department of Physics and Astronomy, Aarhus University Ny Munkegade 120 DK-8000 Aarhus C Denmark
| | - Nigel J Mason
- School of Physical Sciences, University of Kent Canterbury Kent UK
| | - Anita Dawes
- School of Physical Sciences, The Open University Walton Hall Milton Keynes UK +44 (0)1908 654192 +44 (0)1908 332012
| |
Collapse
|
6
|
Sagi R, Akerman M, Ramakrishnan S, Asscher M. Spontaneous polarization of thick solid ammonia films. J Chem Phys 2020; 153:124707. [DOI: 10.1063/5.0017853] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
Affiliation(s)
- Roey Sagi
- Institute of Chemistry, Edmond J. Safra Campus, Givat-Ram, The Hebrew University of Jerusalem, Jerusalem 9190401, Israel
| | - Michelle Akerman
- Institute of Chemistry, Edmond J. Safra Campus, Givat-Ram, The Hebrew University of Jerusalem, Jerusalem 9190401, Israel
| | - Sujith Ramakrishnan
- Institute of Chemistry, Edmond J. Safra Campus, Givat-Ram, The Hebrew University of Jerusalem, Jerusalem 9190401, Israel
| | - Micha Asscher
- Institute of Chemistry, Edmond J. Safra Campus, Givat-Ram, The Hebrew University of Jerusalem, Jerusalem 9190401, Israel
| |
Collapse
|
7
|
Cui J, Gao P, Deng Y. Destruction of Per- and Polyfluoroalkyl Substances (PFAS) with Advanced Reduction Processes (ARPs): A Critical Review. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2020; 54:3752-3766. [PMID: 32162904 DOI: 10.1021/acs.est.9b05565] [Citation(s) in RCA: 127] [Impact Index Per Article: 31.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/10/2023]
Abstract
Advanced reduction processes (ARPs) have emerged as a promising method for destruction of persistent per- and polyfluoroalkyl substances (PFAS) in water due to the generation of short-lived and highly reductive hydrated electrons (eaq-). This study provides a critical review on the mechanisms and performance of reductive destruction of PFAS with eaq-. Unique properties of eaq- and its generation in different ARP systems, particularly UV/sulfite and UV/iodide, are overviewed. Different degradation mechanisms of PFAS chemicals, such as perfluorooctanoic acid (PFOA), perfluorooctanesulfonate (PFOS), and others (e.g., short chain perfluorocarboxylic acids (PFCAs) and perfluorosulfonic acids (PFSAs), per- and polyfluoro dicarboxylic acids, and fluorotelomer carboxylic acids), are reviewed, discussed, and compared. The degradation pathways of these PFAS chemicals rely heavily upon their head groups. For specific PFAS types, fluoroalkyl chain lengths may also affect their reductive degradation patterns. Degradation and defluorination efficiencies of PFAS are considerably influenced by solution chemistry parameters and operating factors, such as pH, dose of chemical solute (i.e., sulfite or iodide) for eaq- photoproduction, dissolved oxygen, humic acid, nitrate, and temperature. Furthermore, implications of the state-of-the-art knowledge on practical PFAS control actions in water industries are discussed and the priority research needs are identified.
Collapse
Affiliation(s)
- Junkui Cui
- Department of Earth and Environmental Studies, Montclair State University, Montclair, New Jersey 07043, United States
| | - Panpan Gao
- Department of Earth and Environmental Studies, Montclair State University, Montclair, New Jersey 07043, United States
- School of Environmental Studies, China University of Geosciences, Wuhan, Hubei Province 430074, P. R. China
| | - Yang Deng
- Department of Earth and Environmental Studies, Montclair State University, Montclair, New Jersey 07043, United States
| |
Collapse
|
8
|
Esmaili S, Bass AD, Cloutier P, Sanche L, Huels MA. Glycine formation in CO 2:CH 4:NH 3 ices induced by 0-70 eV electrons. J Chem Phys 2018; 148:164702. [PMID: 29716196 DOI: 10.1063/1.5021596] [Citation(s) in RCA: 20] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
Glycine (Gly), the simplest amino-acid building-block of proteins, has been identified on icy dust grains in the interstellar medium, icy comets, and ice covered meteorites. These astrophysical ices contain simple molecules (e.g., CO2, H2O, CH4, HCN, and NH3) and are exposed to complex radiation fields, e.g., UV, γ, or X-rays, stellar/solar wind particles, or cosmic rays. While much current effort is focused on understanding the radiochemistry induced in these ices by high energy radiation, the effects of the abundant secondary low energy electrons (LEEs) it produces have been mostly assumed rather than studied. Here we present the results for the exposure of multilayer CO2:CH4:NH3 ice mixtures to 0-70 eV electrons under simulated astrophysical conditions. Mass selected temperature programmed desorption (TPD) of our electron irradiated films reveals multiple products, most notably intact glycine, which is supported by control measurements of both irradiated or un-irradiated binary mixture films, and un-irradiated CO2:CH4:NH3 ices spiked with Gly. The threshold of Gly formation by LEEs is near 9 eV, while the TPD analysis of Gly film growth allows us to determine the "quantum" yield for 70 eV electrons to be about 0.004 Gly per incident electron. Our results show that simple amino acids can be formed directly from simple molecular ingredients, none of which possess preformed C-C or C-N bonds, by the copious secondary LEEs that are generated by ionizing radiation in astrophysical ices.
Collapse
Affiliation(s)
- Sasan Esmaili
- Département de Médecine Nucléaire et Radiobiologie, Faculté de Médecine et des Sciences de la Santé, Université de Sherbrooke, Sherbrooke, Quebec J1H5N4, Canada
| | - Andrew D Bass
- Département de Médecine Nucléaire et Radiobiologie, Faculté de Médecine et des Sciences de la Santé, Université de Sherbrooke, Sherbrooke, Quebec J1H5N4, Canada
| | - Pierre Cloutier
- Département de Médecine Nucléaire et Radiobiologie, Faculté de Médecine et des Sciences de la Santé, Université de Sherbrooke, Sherbrooke, Quebec J1H5N4, Canada
| | - Léon Sanche
- Département de Médecine Nucléaire et Radiobiologie, Faculté de Médecine et des Sciences de la Santé, Université de Sherbrooke, Sherbrooke, Quebec J1H5N4, Canada
| | - Michael A Huels
- Département de Médecine Nucléaire et Radiobiologie, Faculté de Médecine et des Sciences de la Santé, Université de Sherbrooke, Sherbrooke, Quebec J1H5N4, Canada
| |
Collapse
|
9
|
Kalan RE, McCool BA, Tripp CP. Supercritical Fluid Atomic Layer Deposition: Base-Catalyzed Deposition of SiO2. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2016; 32:7170-7179. [PMID: 27338186 DOI: 10.1021/acs.langmuir.6b01669] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/06/2023]
Abstract
An in situ FTIR thin film technique was used to study the sequential atomic layer deposition (ALD) reactions of SiCl4, tetraethyl orthosilicate (TEOS) precursors, and water on nonporous silica powder using supercritical CO2 (sc-CO2) as the solvent. The IR work on nonporous powders was used to identify the reaction sequence for using a sc-CO2-based ALD to tune the pore size of a mesoporous silica. The IR studies showed that only trace adsorption of SiCl4 occurred on the silica, and this was due to the desiccating power of sc-CO2 to remove the adsorbed water from the surface. This was overcome by employing a three-step reaction scheme involving a first step of adsorption of triethylamine (TEA), followed by SiCl4 and then H2O. For TEOS, a three-step reaction sequence using TEA, TEOS, and then water offered no advantage, as the TEOS simply displaced the TEA from the silica surface. A two-step reaction involving the addition of TEOS followed by H2O in a second step did lead to silica film growth. However, higher growth rates were obtained when using a mixture of TEOS/TEA in the first step. The hydrolysis of the adsorbed TEOS was also much slower than that of the adsorbed SiCl4, and this was overcome by using a mixture of water/TEA during the second step. While the three-step process with SiCl4 showed a higher linear growth rate than obtained with two-step process using TEOS/TEA, its use was not practical, as the HCl generated led to corrosion of our sc-CO2 delivery system. However, when applying the two-step ALD reaction using TEOS on an MCM-41 powder, a 0.21 nm decrease in pore diameter was obtained after the first ALD cycle whereas further ALD cycles did not lead to further pore size reduction. This was attributed to the difficulty in removal of the H2O in the pores after the first cycle.
Collapse
Affiliation(s)
- Roghi E Kalan
- Department of Chemistry, University of Maine , Orono, Maine 04469, United States
| | - Benjamin A McCool
- Laboratory for Surface Science and Technology, University of Maine , Orono, Maine 04469, United States
| | - Carl P Tripp
- Department of Chemistry, University of Maine , Orono, Maine 04469, United States
- Laboratory for Surface Science and Technology, University of Maine , Orono, Maine 04469, United States
| |
Collapse
|
10
|
Noble JA, Theule P, Duvernay F, Danger G, Chiavassa T, Ghesquiere P, Mineva T, Talbi D. Kinetics of the NH3 and CO2 solid-state reaction at low temperature. Phys Chem Chem Phys 2014; 16:23604-15. [PMID: 25198107 DOI: 10.1039/c4cp02414a] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
Ammonia and carbon dioxide play an important role in both atmospheric and interstellar ice chemistries. This work presents a theoretical and experimental study of the kinetics of the low-temperature NH3 and CO2 solid-state reaction in ice films, the product of which is ammonium carbamate (NH4(+)NH2COO(-)). It is a first-order reaction with respect to CO2, with a temperature-dependent rate constant fitted to the Arrhenius law in the temperature range 70 K to 90 K, with an activation energy of 5.1 ± 1.6 kJ mol(-1) and a pre-exponential factor of 0.09-0.08(+1.1) s(-1). This work helps to determine the rate of removal of CO2 and NH3, via their conversion into ammonium carbamate, from atmospheric and interstellar ices. We also measure first-order desorption energies of 69.0 ± 0.2 kJ mol(-1) and 76.1 ± 0.1 kJ mol(-1), assuming a pre-exponential factor of 10(13) s(-1), for ammonium carbamate and carbamic acid, respectively.
Collapse
Affiliation(s)
- J A Noble
- Aix-Marseille Univ., CNRS, PIIM UMR 7345, Marseille, 13397, France.
| | | | | | | | | | | | | | | |
Collapse
|
11
|
Rodríguez-Lazcano Y, Maté B, Herrero VJ, Escribano R, Gálvez Ó. The formation of carbamate ions in interstellar ice analogues. Phys Chem Chem Phys 2014; 16:3371-80. [DOI: 10.1039/c3cp53153h] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
|
12
|
Lv XY, Boduch P, Ding JJ, Domaracka A, Langlinay T, Palumbo ME, Rothard H, Strazzulla G. Thermal and energetic processing of ammonia and carbon dioxide bearing solid mixtures. Phys Chem Chem Phys 2014; 16:3433-41. [PMID: 24358469 DOI: 10.1039/c3cp54027h] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Affiliation(s)
- X Y Lv
- School of Nuclear Science and Technology, Lanzhou University, Lanzhou 730000, China
| | | | | | | | | | | | | | | |
Collapse
|
13
|
Bennett CJ, Pirim C, Orlando TM. Space-Weathering of Solar System Bodies: A Laboratory Perspective. Chem Rev 2013; 113:9086-150. [DOI: 10.1021/cr400153k] [Citation(s) in RCA: 107] [Impact Index Per Article: 9.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Chris J. Bennett
- Department of Chemistry & Biochemistry, Georgia Institute of Technology, 901 Atlantic Drive, Atlanta, Georgia 30332, United States
| | - Claire Pirim
- Department of Chemistry & Biochemistry, Georgia Institute of Technology, 901 Atlantic Drive, Atlanta, Georgia 30332, United States
| | - Thomas M. Orlando
- Department of Chemistry & Biochemistry, Georgia Institute of Technology, 901 Atlantic Drive, Atlanta, Georgia 30332, United States
| |
Collapse
|
14
|
Houplin J, Amiaud L, Humblot V, Martin I, Matar E, Azria R, Pradier CM, Lafosse A. Selective terminal function modification of SAMs driven by low-energy electrons (0-15 eV). Phys Chem Chem Phys 2013; 15:7220-7. [PMID: 23558312 DOI: 10.1039/c3cp43750g] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Low-energy electron induced degradation of a model self-assembled monolayer (SAM) of acid terminated alkanethiol was studied under ultra-high vacuum (UHV) conditions at room and low (~40 K) temperatures. Low-energy electron induced chemical modifications of 11-mercaptoundecanoic acid (MUA, HS-(CH2)10-COOH) SAMs deposited on gold were probed in situ as a function of the irradiation energy (<11 eV) by combining two complementary techniques: High Resolution Electron Energy Loss Spectroscopy (HREELS), a surface sensitive vibrational spectroscopy technique, and Electron Stimulated Desorption (ESD) analysis of neutral fragments. The SAM's terminal functions were observed to be selectively damaged at around 1 eV by a resonant electron attachment mechanism, observed to decay by CO, CO2 and H2O formation and desorption. CO2 and H2O were also directly identified at low temperature by vibrational analysis of the irradiated SAMs. At higher irradiation energy, both terminal functions and spacer alkyl chains are damaged upon electron irradiation, by resonant and non-resonant processes.
Collapse
Affiliation(s)
- J Houplin
- Université Paris-Sud, Institut des Sciences Moléculaires d'Orsay (ISMO), UMR 8214, Orsay, France
| | | | | | | | | | | | | | | |
Collapse
|
15
|
Lobo CJ, Martin A, Phillips MR, Toth M. Electron beam induced chemical dry etching and imaging in gaseous NH3 environments. NANOTECHNOLOGY 2012; 23:375302. [PMID: 22922454 DOI: 10.1088/0957-4484/23/37/375302] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/07/2023]
Abstract
We report the use of ammonia (NH(3)) vapor as a new precursor for nanoscale electron beam induced etching (EBIE) of carbon, and an efficient imaging medium for environmental scanning electron microscopy (ESEM). Etching is demonstrated using amorphous carbonaceous nanowires grown by electron beam induced deposition (EBID). It is ascribed to carbon volatilization by hydrogen radicals generated by electron dissociation of NH(3) adsorbates. The volatilization process is also effective at preventing the buildup of residual hydrocarbon impurities that often compromise EBIE, EBID and electron imaging. We also show that ammonia is a more efficient electron imaging medium than H(2)O, which up to now has been the most commonly used ESEM imaging gas.
Collapse
Affiliation(s)
- Charlene J Lobo
- School of Physics and Advanced Materials, University of Technology, Sydney, Broadway, New South Wales 2007, Australia.
| | | | | | | |
Collapse
|
16
|
Vinogradoff V, Duvernay F, Farabet M, Danger G, Theulé P, Borget F, Guillemin JC, Chiavassa T. Acetaldehyde Solid State Reactivity at Low Temperature: Formation of the Acetaldehyde Ammonia Trimer. J Phys Chem A 2012; 116:2225-33. [DOI: 10.1021/jp3000653] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
Affiliation(s)
- V. Vinogradoff
- Laboratoire
de Physique des
Interactions Ioniques et Moléculaires, Centre St-Jérôme, Avenue Escadrille Normandie-Niemen,
13397 Marseille, France
| | - F. Duvernay
- Laboratoire
de Physique des
Interactions Ioniques et Moléculaires, Centre St-Jérôme, Avenue Escadrille Normandie-Niemen,
13397 Marseille, France
| | - M. Farabet
- Laboratoire
de Physique des
Interactions Ioniques et Moléculaires, Centre St-Jérôme, Avenue Escadrille Normandie-Niemen,
13397 Marseille, France
| | - G. Danger
- Laboratoire
de Physique des
Interactions Ioniques et Moléculaires, Centre St-Jérôme, Avenue Escadrille Normandie-Niemen,
13397 Marseille, France
| | - P. Theulé
- Laboratoire
de Physique des
Interactions Ioniques et Moléculaires, Centre St-Jérôme, Avenue Escadrille Normandie-Niemen,
13397 Marseille, France
| | - F. Borget
- Laboratoire
de Physique des
Interactions Ioniques et Moléculaires, Centre St-Jérôme, Avenue Escadrille Normandie-Niemen,
13397 Marseille, France
| | - J. C. Guillemin
- Ecole Nationale Supérieure de Chimie de Rennes, CNRS, UMR 6226,
Avenue du Général Leclerc, CS 50837, 35708 Rennes Cedex
7, France
| | - T. Chiavassa
- Laboratoire
de Physique des
Interactions Ioniques et Moléculaires, Centre St-Jérôme, Avenue Escadrille Normandie-Niemen,
13397 Marseille, France
| |
Collapse
|
17
|
Hamann T, Kankate L, Böhler E, Bredehöft JH, Zhang FM, Gölzhäuser A, Swiderek P. Functionalization of a self-assembled monolayer driven by low-energy electron exposure. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2012; 28:367-76. [PMID: 22084928 DOI: 10.1021/la2027219] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/11/2023]
Abstract
Self-assembled monolayers (SAMs) of 10-undecene-1-thiol on Au were functionalized with nitrogen-containing groups using an approach in which multilayer ammonia (NH(3)) films were deposited at low temperature onto the SAMs and subsequently exposed to 15 eV electrons. The result of this process was investigated after removal of the remaining NH(3) by annealing to room temperature using high-resolution electron energy loss spectroscopy (HREELS) and X-ray photoelectron spectroscopy (XPS). HREELS shows that the CC double bonds disappear during electron exposure, while XPS gives evidence that about 25% of the terminal double bonds of the SAM were functionalized. Also, XPS shows that a sufficiently thick NH(3) layer protects the underlying SAM from electron-induced damage. The process suggested here thus represents a particularly gentle approach to the functionalization of ultrathin molecular layers. Thermal desorption spectrometry (TDS) and electron-stimulated desorption (ESD) experiments on condensed layers of NH(3) reveal production of N(2) but show that significant amounts of the initial NH(3) as well as N(2) produced during electron exposure desorb. Hydrogen released upon formation of N(2) is held responsible for the reduction of double bonds and protection of the SAMs from damage.
Collapse
Affiliation(s)
- T Hamann
- Institute of Applied and Physical Chemistry, University of Bremen, Fachbereich 2 (Chemie/Biologie), Leobener Straße/NW 2, Postfach 330440, D-28334 Bremen, Germany
| | | | | | | | | | | | | |
Collapse
|
18
|
Modification of surface properties of thin polysaccharide films by low-energy electron exposure. Carbohydr Polym 2011. [DOI: 10.1016/j.carbpol.2010.08.029] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
|