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Ucar S, Nielsen AR, Mojsoska B, Dideriksen K, Andreassen JP, Zuckermann RN, Sand KK. Exploiting Saturation Regimes and Surface Effects to Tune Composite Design: Single Platelet Nanocomposites of Peptoid Nanosheets and CaCO 3. ACS Appl Mater Interfaces 2024; 16:19496-19506. [PMID: 38568217 DOI: 10.1021/acsami.4c00434] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 04/19/2024]
Abstract
Mineral-polymer composites found in nature exhibit exceptional structural properties essential to their function, and transferring these attributes to the synthetic design of functional materials holds promise across various sectors. Biomimetic fabrication of nanocomposites introduces new pathways for advanced material design and explores biomineralization strategies. This study presents a novel approach for producing single platelet nanocomposites composed of CaCO3 and biomimetic peptoid (N-substituted glycines) polymers, akin to the bricks found in the brick-and-mortar structure of nacre, the inner layer of certain mollusc shells. The significant aspect of the proposed strategy is the use of organic peptoid nanosheets as the scaffolds for brick formation, along with their controlled mineralization in solution. Here, we employ the B28 peptoid nanosheet as a scaffold, which readily forms free-floating zwitterionic bilayers in aqueous solution. The peptoid nanosheets were mineralized under consistent initial conditions (σcalcite = 1.2, pH 9.00), with variations in mixing conditions and supersaturation profiles over time aimed at controlling the final product. Nanosheets were mineralized in both feedback control experiments, where supersaturation was continuously replenished by titrant addition and in batch experiments without a feedback loop. Complete coverage of the nanosheet surface by amorphous calcium carbonate was achieved under specific conditions with feedback control mineralization, whereas vaterite was the primary CaCO3 phase observed after batch experiments. Thermodynamic calculations suggest that time-dependent supersaturation profiles as well as the spatial distribution of supersaturation are effective controls for tuning the mineralization extent and product. We anticipate that the control strategies outlined in this work can serve as a foundation for the advanced and scalable fabrication of nanocomposites as building blocks for nacre-mimetic and functional materials.
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Affiliation(s)
- Seniz Ucar
- Department of Chemical Engineering, Norwegian University of Science and Technology, Trondheim 7491, Norway
- Department of Metallurgical and Materials Engineering, Middle East Technical University, Ankara 06800, Turkiye
| | - Anne R Nielsen
- Nano-Science Center, Department of Chemistry, University of Copenhagen, Copenhagen 2100, Denmark
| | - Biljana Mojsoska
- Department of Science and Environment, Roskilde University, Roskilde 4000, Denmark
| | - Knud Dideriksen
- Nano-Science Center, Department of Chemistry, University of Copenhagen, Copenhagen 2100, Denmark
| | - Jens-Petter Andreassen
- Department of Chemical Engineering, Norwegian University of Science and Technology, Trondheim 7491, Norway
| | - Ronald N Zuckermann
- Biological Nanostructures Facility, The Molecular Foundry, Lawrence Berkeley National Laboratory, Berkeley, California CA 94720, United States
| | - Karina K Sand
- Nano-Science Center, Department of Chemistry, University of Copenhagen, Copenhagen 2100, Denmark
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2
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Kjær KH, Winther Pedersen M, De Sanctis B, De Cahsan B, Korneliussen TS, Michelsen CS, Sand KK, Jelavić S, Ruter AH, Schmidt AMA, Kjeldsen KK, Tesakov AS, Snowball I, Gosse JC, Alsos IG, Wang Y, Dockter C, Rasmussen M, Jørgensen ME, Skadhauge B, Prohaska A, Kristensen JÅ, Bjerager M, Allentoft ME, Coissac E, Rouillard A, Simakova A, Fernandez-Guerra A, Bowler C, Macias-Fauria M, Vinner L, Welch JJ, Hidy AJ, Sikora M, Collins MJ, Durbin R, Larsen NK, Willerslev E. A 2-million-year-old ecosystem in Greenland uncovered by environmental DNA. Nature 2022; 612:283-291. [PMID: 36477129 PMCID: PMC9729109 DOI: 10.1038/s41586-022-05453-y] [Citation(s) in RCA: 22] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2021] [Accepted: 10/18/2022] [Indexed: 12/12/2022]
Abstract
Late Pliocene and Early Pleistocene epochs 3.6 to 0.8 million years ago1 had climates resembling those forecasted under future warming2. Palaeoclimatic records show strong polar amplification with mean annual temperatures of 11-19 °C above contemporary values3,4. The biological communities inhabiting the Arctic during this time remain poorly known because fossils are rare5. Here we report an ancient environmental DNA6 (eDNA) record describing the rich plant and animal assemblages of the Kap København Formation in North Greenland, dated to around two million years ago. The record shows an open boreal forest ecosystem with mixed vegetation of poplar, birch and thuja trees, as well as a variety of Arctic and boreal shrubs and herbs, many of which had not previously been detected at the site from macrofossil and pollen records. The DNA record confirms the presence of hare and mitochondrial DNA from animals including mastodons, reindeer, rodents and geese, all ancestral to their present-day and late Pleistocene relatives. The presence of marine species including horseshoe crab and green algae support a warmer climate than today. The reconstructed ecosystem has no modern analogue. The survival of such ancient eDNA probably relates to its binding to mineral surfaces. Our findings open new areas of genetic research, demonstrating that it is possible to track the ecology and evolution of biological communities from two million years ago using ancient eDNA.
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Affiliation(s)
- Kurt H Kjær
- Lundbeck Foundation GeoGenetics Centre, Globe Institute, University of Copenhagen, Copenhagen, Denmark.
| | - Mikkel Winther Pedersen
- Lundbeck Foundation GeoGenetics Centre, Globe Institute, University of Copenhagen, Copenhagen, Denmark
| | - Bianca De Sanctis
- Department of Zoology, University of Cambridge, Cambridge, UK
- Department of Genetics, University of Cambridge, Cambridge, UK
| | - Binia De Cahsan
- Section for Molecular Ecology and Evolution, The Globe Institute, Faculty of Health and Medical Sciences, Copenhagen, Denmark
| | - Thorfinn S Korneliussen
- Lundbeck Foundation GeoGenetics Centre, Globe Institute, University of Copenhagen, Copenhagen, Denmark
| | - Christian S Michelsen
- Lundbeck Foundation GeoGenetics Centre, Globe Institute, University of Copenhagen, Copenhagen, Denmark
- Niels Bohr Institute, University of Copenhagen, Copenhagen, Denmark
| | - Karina K Sand
- Lundbeck Foundation GeoGenetics Centre, Globe Institute, University of Copenhagen, Copenhagen, Denmark
| | - Stanislav Jelavić
- Lundbeck Foundation GeoGenetics Centre, Globe Institute, University of Copenhagen, Copenhagen, Denmark
- Université Grenoble Alpes, Université Savoie Mont Blanc, CNRS, IRD, Université Gustave Eiffel, ISTerre, Grenoble, France
| | - Anthony H Ruter
- Lundbeck Foundation GeoGenetics Centre, Globe Institute, University of Copenhagen, Copenhagen, Denmark
| | - Astrid M A Schmidt
- Nordic Foundation for Development and Ecology (NORDECO), Copenhagen, Denmark
- DIS Study Abroad in Scandinavia, University of Copenhagen, Copenhagen, Denmark
| | - Kristian K Kjeldsen
- Department of Glaciology and Climate, Geological Survey of Denmark and Greenland, Copenhagen, Denmark
| | - Alexey S Tesakov
- Geological Institute, Russian Academy of Sciences, Moscow, Russia
| | - Ian Snowball
- Department of Earth Sciences, Uppsala University, Uppsala, Sweden
| | - John C Gosse
- Department of Earth and Environmental Sciences, Dalhousie University, Halifax, Nova Scotia, Canada
| | - Inger G Alsos
- The Arctic University Museum of Norway, UiT-The Arctic University of Norway, Tromsø, Norway
| | - Yucheng Wang
- Lundbeck Foundation GeoGenetics Centre, Globe Institute, University of Copenhagen, Copenhagen, Denmark
- Department of Zoology, University of Cambridge, Cambridge, UK
| | | | | | | | | | - Ana Prohaska
- Lundbeck Foundation GeoGenetics Centre, Globe Institute, University of Copenhagen, Copenhagen, Denmark
- Department of Zoology, University of Cambridge, Cambridge, UK
| | - Jeppe Å Kristensen
- Environmental Change Institute, School of Geography and the Environment, University of Oxford, Oxford, UK
- Geological Survey of Denmark and Greenland, (GEUS), Copenhagen, Denmark
| | - Morten Bjerager
- Department of Geophysics and Sedimentary Basins, Geological Survey of Denmark and Greenland, Copenhagen, Denmark
| | - Morten E Allentoft
- Lundbeck Foundation GeoGenetics Centre, Globe Institute, University of Copenhagen, Copenhagen, Denmark
- Trace and Environmental DNA (TrEnD) Laboratory, School of Molecular and Life Sciences, Curtin University, Perth, Western Australia, Australia
| | - Eric Coissac
- The Arctic University Museum of Norway, UiT-The Arctic University of Norway, Tromsø, Norway
- University of Grenoble-Alpes, Université Savoie Mont Blanc, CNRS, LECA, Grenoble, France
| | - Alexandra Rouillard
- Lundbeck Foundation GeoGenetics Centre, Globe Institute, University of Copenhagen, Copenhagen, Denmark
- Department of Geosciences, UiT-The Arctic University of Norway, Tromsø, Norway
| | | | - Antonio Fernandez-Guerra
- Lundbeck Foundation GeoGenetics Centre, Globe Institute, University of Copenhagen, Copenhagen, Denmark
| | - Chris Bowler
- Institut de Biologie de l'Ecole Normale Supérieure (IBENS), Ecole Normale Supérieure, CNRS, INSERM Université PSL, Paris, France
| | - Marc Macias-Fauria
- School of Geography and the Environment, University of Oxford, Oxford, UK
| | - Lasse Vinner
- Lundbeck Foundation GeoGenetics Centre, Globe Institute, University of Copenhagen, Copenhagen, Denmark
| | - John J Welch
- Department of Genetics, University of Cambridge, Cambridge, UK
| | - Alan J Hidy
- Center for Accelerator Mass Spectrometry, Lawrence Livermore National Laboratory, Livermore, CA, USA
| | - Martin Sikora
- Lundbeck Foundation GeoGenetics Centre, Globe Institute, University of Copenhagen, Copenhagen, Denmark
| | - Matthew J Collins
- Department of Archaeology, University of Cambridge, Cambridge, UK
- Section for GeoBiology, Globe Institute, University of Copenhagen, Copenhagen, Denmark
| | - Richard Durbin
- Department of Genetics, University of Cambridge, Cambridge, UK
| | - Nicolaj K Larsen
- Lundbeck Foundation GeoGenetics Centre, Globe Institute, University of Copenhagen, Copenhagen, Denmark
| | - Eske Willerslev
- Lundbeck Foundation GeoGenetics Centre, Globe Institute, University of Copenhagen, Copenhagen, Denmark.
- Department of Zoology, University of Cambridge, Cambridge, UK.
- MARUM, University of Bremen, Bremen, Germany.
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Sand KK, Jelavić S, Dobberschütz S, Ashby PD, Marshall MJ, Dideriksen K, Stipp SLS, Kerisit SN, Friddle RW, DeYoreo JJ. Mechanistic insight into biopolymer induced iron oxide mineralization through quantification of molecular bonding. Nanoscale Adv 2020; 2:3323-3333. [PMID: 36134299 PMCID: PMC9417541 DOI: 10.1039/d0na00138d] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 02/19/2020] [Accepted: 06/12/2020] [Indexed: 06/16/2023]
Abstract
Microbial production of iron (oxyhydr)oxides on polysaccharide rich biopolymers occurs on such a vast scale that it impacts the global iron cycle and has been responsible for major biogeochemical events. Yet the physiochemical controls these biopolymers exert on iron (oxyhydr)oxide formation are poorly understood. Here we used dynamic force spectroscopy to directly probe binding between complex, model and natural microbial polysaccharides and common iron (oxyhydr)oxides. Applying nucleation theory to our results demonstrates that if there is a strong attractive interaction between biopolymers and iron (oxyhydr)oxides, the biopolymers decrease the nucleation barriers, thus promoting mineral nucleation. These results are also supported by nucleation studies and density functional theory. Spectroscopic and thermogravimetric data provide insight into the subsequent growth dynamics and show that the degree and strength of water association with the polymers can explain the influence on iron (oxyhydr)oxide transformation rates. Combined, our results provide a mechanistic basis for understanding how polymer-mineral-water interactions alter iron (oxyhydr)oxides nucleation and growth dynamics and pave the way for an improved understanding of the consequences of polymer induced mineralization in natural systems.
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Affiliation(s)
- K K Sand
- Physical Sciences Division, Pacific Northwest National Laboratory Richland WA USA
- Molecular Foundry, Lawrence Berkeley National Laboratory Berkeley CA USA
| | - S Jelavić
- Nano-Science Center, Department of Chemistry, University of Copenhagen Denmark
| | - S Dobberschütz
- Nano-Science Center, Department of Chemistry, University of Copenhagen Denmark
| | - P D Ashby
- Molecular Foundry, Lawrence Berkeley National Laboratory Berkeley CA USA
| | - M J Marshall
- Biologic Sciences Division, Pacific Northwest National Laboratory Richland WA USA
| | - K Dideriksen
- Nano-Science Center, Department of Chemistry, University of Copenhagen Denmark
| | - S L S Stipp
- Nano-Science Center, Department of Chemistry, University of Copenhagen Denmark
| | - S N Kerisit
- Physical Sciences Division, Pacific Northwest National Laboratory Richland WA USA
| | - R W Friddle
- Sandia National Laboratories Livermore California 94550 USA
| | - J J DeYoreo
- Physical Sciences Division, Pacific Northwest National Laboratory Richland WA USA
- Department of Material Science and Engineering, University of Washington Seattle WA USA
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Nielsen AR, Jelavić S, Murray D, Rad B, Andersson MP, Ceccato M, Mitchell AC, Stipp SLS, Zuckermann RN, Sand KK. Thermodynamic and Kinetic Parameters for Calcite Nucleation on Peptoid and Model Scaffolds: A Step toward Nacre Mimicry. Cryst Growth Des 2020; 20:3762-3771. [PMID: 33192182 PMCID: PMC7660692 DOI: 10.1021/acs.cgd.0c00029] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 01/09/2020] [Revised: 04/22/2020] [Indexed: 06/11/2023]
Abstract
The production of novel composite materials, assembled using biomimetic polymers known as peptoids (N-substituted glycines) to nucleate CaCO3, can open new pathways for advanced material design. However, a better understanding of the heterogeneous CaCO3 nucleation process is a necessary first step. We determined the thermodynamic and kinetic parameters for calcite nucleation on self-assembled monolayers (SAMs) of nanosheet-forming peptoid polymers and simpler, alkanethiol analogues. We used nucleation rate studies to determine the net interfacial free energy (γ net) for the peptoid-calcite interface and for SAMs terminated with carboxyl headgroups, amine headgroups, or a mix of the two. We compared the results with γ net determined from dynamic force spectroscopy (DFS) and from density functional theory (DFT), using COSMO-RS simulations. Calcite nucleation has a lower thermodynamic barrier on the peptoid surface than on carboxyl and amine SAMs. From the relationship between nucleation rate (J 0) and saturation state, we found that under low-saturation conditions, i.e. <3.3 (pH 9.0), nucleation on the peptoid substrate was faster than that on all of the model surfaces, indicating a thermodynamic drive toward heterogeneous nucleation. When they are taken together, our results indicate that nanosheet-forming peptoid monolayers can serve as an organic template for CaCO3 polymorph growth.
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Affiliation(s)
- Anne R. Nielsen
- Nano-Science
Center, Department of Chemistry, University
of Copenhagen, Copenhagen, Denmark
| | - Stanislav Jelavić
- Nano-Science
Center, Department of Chemistry, University
of Copenhagen, Copenhagen, Denmark
| | - Daniel Murray
- Biological
Nanostructures Facility, The Molecular Foundry, Lawrence Berkeley National Laboratory, Berkeley, California, United States
| | - Behzad Rad
- Biological
Nanostructures Facility, The Molecular Foundry, Lawrence Berkeley National Laboratory, Berkeley, California, United States
| | - Martin P. Andersson
- Nano-Science
Center, Department of Chemistry, University
of Copenhagen, Copenhagen, Denmark
| | - Marcel Ceccato
- Nano-Science
Center, Department of Chemistry, University
of Copenhagen, Copenhagen, Denmark
| | - Andrew C. Mitchell
- Department
of Geography & Earth Sciences, Aberystwyth
University, Aberystwyth, United Kingdom
| | - Susan L. S. Stipp
- Nano-Science
Center, Department of Chemistry, University
of Copenhagen, Copenhagen, Denmark
| | - Ronald N. Zuckermann
- Biological
Nanostructures Facility, The Molecular Foundry, Lawrence Berkeley National Laboratory, Berkeley, California, United States
| | - Karina K. Sand
- Department
of Geography & Earth Sciences, Aberystwyth
University, Aberystwyth, United Kingdom
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Abstract
The production of polymers for controlling calcite growth is a well-known approach in biomineralising organisms. Numerous studies have shown that polymers significantly influenced the growth rate and morphology of CaCO3 but little is known about how the polymers are actually controlled by the organisms. Here we show that cations control the effect of polysaccharides and that these processes have been in place for at least 60 million years. We studied the interaction between cleaved samples of pure calcite and ancient coccolith associated polysaccharides (aPS) that we had extracted from the samples of Cretaceous chalk, in solutions that contained one of the common seawater cations, K+, Ca2+, Mg2+ and Sr2+. With atomic and chemical force microscopy (AFM and CFM), we showed that K+, Ca2+ and Sr2+ complex aPS through a weak, outer sphere bonding, giving the aPS affinity to sites on steps and terraces. In contrast, Mg2+ enhanced the formation of stronger and longer aPS complexes, resulting in low affinity to calcite terraces and strong affinity to steps. It is known that adsorption is influenced by ionic potential and ionic strength. Our results show that cation-polysaccharide complexing can modify the effectiveness of the polymer. Thus, creating organic molecules with cation complexing ability is an effective strategy for regulating mineral growth, both now and in the past.
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Affiliation(s)
- K K Sand
- Nano-Science Center, Department of Chemistry, University of Copenhagen, Denmark.
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6
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Abstract
Higher organisms as well as medical and technological materials exploit mineral-polymer interactions, however, mechanistic understanding of these interactions is poorly constrained. Dynamic force spectroscopy can probe the free energy landscape of interacting bonds, but interpretations are challenged by the complex mechanical behavior of polymers. Here we restate the difficulties inherent to applying DFS to polymer-linked adhesion and present an approach to gain quantitative insight into polymer-mineral binding.
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Affiliation(s)
- K K Sand
- Physical Sciences Division, Pacific Northwest National Laboratory, Richland, WA, USA. .,Nano-Science Center, Department of Chemistry, University of Copenhagen, Denmark and Geography & Earth Sciences, Aberystwyth University, Aberystwyth, United Kingdom.
| | - R W Friddle
- Sandia National Laboratories, Livermore, California, 94550, USA.
| | - J J DeYoreo
- Physical Sciences Division, Pacific Northwest National Laboratory, Richland, WA, USA.,Department of Materials Science and Engineering, University of Washington, Seattle, WA, 98195, USA
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Andersson MP, Dobberschütz S, Sand KK, Tobler DJ, De Yoreo JJ, Stipp SLS. A Microkinetic Model of Calcite Step Growth. Angew Chem Int Ed Engl 2016; 55:11086-90. [PMID: 27532505 DOI: 10.1002/anie.201604357] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/04/2016] [Revised: 06/29/2016] [Indexed: 11/05/2022]
Abstract
In spite of decades of research, mineral growth models based on ion attachment and detachment rates fail to predict behavior beyond a narrow range of conditions. Here we present a microkinetic model that accurately reproduces calcite growth over a very wide range of published experimental data for solution composition, saturation index, pH and impurities. We demonstrate that polynuclear complexes play a central role in mineral growth at high supersaturation and that a classical complexation model is sufficient to reproduce measured rates. Dehydration of the attaching species, not the mineral surface, is rate limiting. Density functional theory supports our conclusions. The model provides new insights into the molecular mechanisms of mineral growth that control biomineralization, mineral scaling and industrial material synthesis.
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Affiliation(s)
- M P Andersson
- Nano-Science Center, Department of Chemistry, University of Copenhagen, Denmark.
| | - S Dobberschütz
- Nano-Science Center, Department of Chemistry, University of Copenhagen, Denmark
| | - K K Sand
- Nano-Science Center, Department of Chemistry, University of Copenhagen, Denmark.,Physical Sciences Division, Pacific Northwest National Laboratory, Richland, WA, 99352, USA
| | - D J Tobler
- Nano-Science Center, Department of Chemistry, University of Copenhagen, Denmark
| | - J J De Yoreo
- Physical Sciences Division, Pacific Northwest National Laboratory, Richland, WA, 99352, USA.,Departments of Materials Science and Engineering and of Chemistry, University of Washington, Seattle, WA, 98195, USA
| | - S L S Stipp
- Nano-Science Center, Department of Chemistry, University of Copenhagen, Denmark
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Sand KK, Yang M, Makovicky E, Cooke DJ, Hassenkam T, Bechgaard K, Stipp SLS. Binding of ethanol on calcite: the role of the OH bond and its relevance to biomineralization. Langmuir 2010; 26:15239-15247. [PMID: 20812690 DOI: 10.1021/la101136j] [Citation(s) in RCA: 45] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/26/2023]
Abstract
The interaction of OH-containing compounds with calcite, CaCO(3), such as is required for the processes that control biomineralization, has been investigated in a low-water solution. We used ethanol (EtOH) as a simple, model, OH-containing organic compound, and observed the strength of its adsorption on calcite relative to OH from water and the consequences of the differences in interaction on crystal growth and dissolution. A combination of atomic force microscopy (AFM) and molecular dynamics (MD) simulations showed that EtOH attachment on calcite is stronger than HOH binding and that the first adsorbed layer of ethanol is highly ordered. The strong ordering of the ethanol molecules has important implications for mineral growth and dissolution because it produces a hydrophobic layer. Ethanol ordering is disturbed along steps and at defect sites, providing a bridge from the bulk solution to the surface. The strong influence of calcite in structuring ethanol extends further into the liquid than expected from electrical double-layer theory. This suggests that in fluids where water activity is low, such as in biological systems optimized for biomineralization, organic molecules can control ion transport to and from the mineral surface, confining it to specific locations, thus providing the organism with control for biomineral morphology.
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Affiliation(s)
- K K Sand
- Nano-Science Center, Department of Chemistry, University of Copenhagen, Denmark.
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9
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Abstract
Molecular dynamics simulations have been used to model the interaction between ethanol, water, and the {1014} surface of calcite. Our results demonstrate that a single ethanol molecule is able to form two interactions with the mineral surface (both Ca-O and O-H), resulting in a highly ordered, stable adsorption layer. In contrast, a single water molecule can only form one or other of these interactions and is thus less well bound, resulting in a more unstable adsorption layer. Consequently, when competitive adsorption is considered, ethanol dominates the adsorption layer that forms even when the starting configuration consists of a complete monolayer of water at the surface. The computational results are in good agreement with the results from atomic force microscopy experiments where it is observed that a layer of ethanol remains attached to the calcite surface, decreasing its ability to interact with water and for growth at the {1014} surface to occur. This observation, and its corresponding molecular explanation, may give some insight into the ability to control crystal form using mixtures of different organic solvents.
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Affiliation(s)
- D J Cooke
- Department of Chemical and Biological Sciences, University of Huddersfield, United Kingdom.
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