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Hammond OS, Bousrez G, Mehler F, Li S, Shimpi MR, Doutch J, Cavalcanti L, Glavatskih S, Antzutkin ON, Rutland MW, Mudring AV. Molecular Architecture Effects on Bulk Nanostructure in Bis(Orthoborate) Ionic Liquids. SMALL (WEINHEIM AN DER BERGSTRASSE, GERMANY) 2023; 19:e2300912. [PMID: 37395635 DOI: 10.1002/smll.202300912] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/01/2023] [Revised: 04/11/2023] [Indexed: 07/04/2023]
Abstract
A series of 19 ionic liquids (ILs) based on phosphonium and imidazolium cations of varying alkyl-chain lengths with the orthoborate anions bis(oxalato)borate [BOB]- , bis(mandelato)borate, [BMB]- and bis(salicylato)borate, [BScB]- , are synthesized and studied using small-angle neutron scattering (SANS). All measured systems display nanostructuring, with 1-methyl-3-n-alkyl imidazolium-orthoborates forming clearly bicontinuous L3 spongelike phases when the alkyl chains are longer than C6 (hexyl). L3 phases are fitted using the Teubner and Strey model, and diffusely-nanostructured systems are primarily fitted using the Ornstein-Zernicke correlation length model. Strongly-nanostructured systems have a strong dependence on the cation, with molecular architecture variation explored to determine the driving forces for self-assembly. The ability to form well-defined complex phases is effectively extinguished in several ways: methylation of the most acidic imidazolium ring proton, replacing the imidazolium 3-methyl group with a longer hydrocarbon chain, substitution of [BOB]- by [BMB]- , or exchanging the imidazolium for phosphonium systems, irrespective of phosphonium architecture. The results suggest there is only a small window of opportunity, in terms of molecular amphiphilicity and cation:anion volume matching, for the formation of stable extensive bicontinuous domains in pure bulk orthoborate-based ILs. Particularly important for self-assembly processes appear to be the ability to form H-bonding networks, which offer additional versatility in imidazolium systems.
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Affiliation(s)
- Oliver S Hammond
- Department of Materials and Environmental Chemistry, Stockholm University, Stockholm, SE-114 18, Sweden
- Department of Biological and Chemical Engineering and iNANO, Aarhus University, Aarhus C, 8000, Denmark
| | - Guillaume Bousrez
- Department of Materials and Environmental Chemistry, Stockholm University, Stockholm, SE-114 18, Sweden
- Department of Biological and Chemical Engineering and iNANO, Aarhus University, Aarhus C, 8000, Denmark
| | - Filip Mehler
- Division of Surface and Corrosion Science, School of Engineering Sciences in Chemistry, Biotechnology and Health, KTH Royal Institute of Technology, Stockholm, SE-100 40, Sweden
| | - Sichao Li
- Division of Surface and Corrosion Science, School of Engineering Sciences in Chemistry, Biotechnology and Health, KTH Royal Institute of Technology, Stockholm, SE-100 40, Sweden
| | - Manishkumar R Shimpi
- Department of Materials and Environmental Chemistry, Stockholm University, Stockholm, SE-114 18, Sweden
- Chemistry of Interfaces, Luleå University of Technology, Luleå, SE-971 87, Sweden
| | - James Doutch
- ISIS Neutron & Muon Source, Science and Technology Facilities Council, Rutherford Appleton Laboratory, Harwell-Oxford, OX11 0QX, UK
| | - Leide Cavalcanti
- ISIS Neutron & Muon Source, Science and Technology Facilities Council, Rutherford Appleton Laboratory, Harwell-Oxford, OX11 0QX, UK
| | - Sergei Glavatskih
- Department of Engineering Design, KTH Royal Institute of Technology, Stockholm, SE-10044, Sweden
- School of Chemistry, University of New South Wales, Sydney, 2052, Australia
- Department of Electromechanical, Systems and Metal Engineering, Ghent University, Ghent, B-9052, Belgium
| | - Oleg N Antzutkin
- Chemistry of Interfaces, Luleå University of Technology, Luleå, SE-971 87, Sweden
| | - Mark W Rutland
- Division of Surface and Corrosion Science, School of Engineering Sciences in Chemistry, Biotechnology and Health, KTH Royal Institute of Technology, Stockholm, SE-100 40, Sweden
- School of Chemistry, University of New South Wales, Sydney, 2052, Australia
- Bioeconomy and Health Department Materials and Surface Design, RISE Research Institutes of Sweden, Stockholm, SE-114 86, Sweden
- Laboratoire de Tribologie et Dynamique des Systèmes, École Centrale de Lyon, Lyon, 69130, France
| | - Anja-Verena Mudring
- Department of Materials and Environmental Chemistry, Stockholm University, Stockholm, SE-114 18, Sweden
- Department of Biological and Chemical Engineering and iNANO, Aarhus University, Aarhus C, 8000, Denmark
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Lu Y, Watanabe S, Sasaki S, Glavatskih S. Lubricity of chelated orthoborate–phosphonium ionic liquids on tetrahedral amorphous carbon and steel surfaces. J Mol Liq 2023. [DOI: 10.1016/j.molliq.2023.121571] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/08/2023]
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Khajeh A, Rahman MH, Liu T, Panwar P, Menezes PL, Martini A. Thermal decomposition of phosphonium salicylate and phosphonium benzoate ionic liquids. J Mol Liq 2022. [DOI: 10.1016/j.molliq.2022.118700] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/24/2023]
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Munavirov B, Black JJ, Shah FU, Leckner J, Rutland MW, Harper JB, Glavatskih S. The effect of anion architecture on the lubrication chemistry of phosphonium orthoborate ionic liquids. Sci Rep 2021; 11:24021. [PMID: 34912003 PMCID: PMC8674318 DOI: 10.1038/s41598-021-02763-5] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/27/2021] [Accepted: 11/23/2021] [Indexed: 11/26/2022] Open
Abstract
Phosphonium ionic liquids with orthoborate anions have been studied in terms of their interfacial film formation, both physisorbed and sacrificial from chemical breakdown, in sheared contacts of varying harshness. The halogen-free anion architecture was varied through (i) the heteronuclear ring size, (ii) the hybridisation of the constituent atoms, and (iii) the addition of aryl functionalities. Time of Flight-Secondary Ion Mass Spectrometry analysis revealed the extent of sacrificial tribofilm formation allowing the relative stability of the ionic liquids under tribological conditions to be determined and their breakdown mechanisms to be compared to simple thermal decomposition. Overall, ionic liquids outperformed reference oils as lubricants; in some cases, sacrificial films were formed (with anion breakdown a necessary precursor to phosphonium cation decomposition) while in other cases, a protective, self-assembly lubricant layer or hybrid film was formed. The salicylate-based anion was the most chemically stable and decomposed only slightly even under the harshest conditions. It was further found that surface topography influenced the degree of breakdown through enhanced material transport and replenishment. This work thus unveils the relationship between ionic liquid composition and structure, and the ensuing inter- and intra-molecular interactions and chemical stability, and demonstrates the intrinsic tuneability of an ionic liquid lubrication technology.
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Affiliation(s)
- Bulat Munavirov
- System and Component Design, KTH Royal Institute of Technology, 100 44, Stockholm, Sweden
| | - Jeffrey J Black
- School of Chemistry, University of New South Wales, UNSW Sydney, Sydney, NSW, 2052, Australia
| | - Faiz Ullah Shah
- Chemistry of Interfaces, Luleå University of Technology, 97 187, Luleå, Sweden
| | - Johan Leckner
- Axel Christiernsson International AB, 44911, Nol, Sweden
| | - Mark W Rutland
- School of Chemistry, University of New South Wales, UNSW Sydney, Sydney, NSW, 2052, Australia.
- Division of Surface and Corrosion Science, KTH Royal Institute of Technology, 100 44, Stockholm, Sweden.
- Surfaces, Processes and Formulation, RISE Research Institutes of Sweden, 100 44, Stockholm, Sweden.
| | - Jason B Harper
- School of Chemistry, University of New South Wales, UNSW Sydney, Sydney, NSW, 2052, Australia.
| | - Sergei Glavatskih
- System and Component Design, KTH Royal Institute of Technology, 100 44, Stockholm, Sweden.
- School of Chemistry, University of New South Wales, UNSW Sydney, Sydney, NSW, 2052, Australia.
- Department of Electromechanical, Systems and Metal Engineering, Ghent University, 9052, Ghent, Belgium.
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Arkhipova EA, Ivanov AS, Reshetko SS, Aleshin DY, Maslakov KI, Kupreenko SY, Savilov SV. Transport properties of nitrile and carbonate solutions of [P66614][NTf 2] ionic liquid, its thermal degradation and non-isothermal kinetics of decomposition. Phys Chem Chem Phys 2021; 23:23909-23921. [PMID: 34651626 DOI: 10.1039/d1cp03549e] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/15/2023]
Abstract
The electrical conductivity, density and diffusion coefficients of trihexyl(tetradecyl)phosphonium bis(trifluoromethylsulfonyl)amide ([P66614][NTf2]) ionic liquid and its binary solutions in acetonitrile, propionitrile, dimethyl and diethyl carbonates were measured in the temperature range of 293-348 K. The electrical conductivity - ionic liquid mole fraction dependencies for the binary solutions were fitted with the empirical Casteel-Amis equation. The temperature dependencies of electrical conductivity were analyzed using the Arrhenius, Litovitz and Vogel-Fulcher-Tammann approaches. The dependences of the Arrhenius activation energy and pre-exponential factor on the mole fraction of ionic liquid in the solutions were fitted with the empirical equations proposed in the literature. The thermo-gravimetric analysis combined with mass spectrometry demonstrated the high thermal stability of [P66614][NTf2] up to 600 K. At higher temperatures the decomposition of [P66614][NTf2] proceeded via the elimination of alkyl radicals as a result of the nucleophilic attack of reactive intermediates to the [P66614]+ cation with the formation of trialkylphosphines. The activation energies of the thermal destruction of [P66614][NTf2] were calculated using the Kissinger equation and non-linear integral isoconversional model.
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Affiliation(s)
- Ekaterina A Arkhipova
- Department of Chemistry, Lomonosov Moscow State University, 1-3 Leninskiye Gory, Moscow 119991, Russia.
| | - Anton S Ivanov
- Department of Chemistry, Lomonosov Moscow State University, 1-3 Leninskiye Gory, Moscow 119991, Russia.
| | - Sergei S Reshetko
- Department of Chemistry, Lomonosov Moscow State University, 1-3 Leninskiye Gory, Moscow 119991, Russia.
| | - Dmitry Yu Aleshin
- A. N. Nesmeyanov Institute of Organoelement Compounds, Russian Academy of Sciences, Vavilov str., 28, Moscow 119991, Russia
| | - Konstantin I Maslakov
- Department of Chemistry, Lomonosov Moscow State University, 1-3 Leninskiye Gory, Moscow 119991, Russia.
| | - Stepan Yu Kupreenko
- Department of Chemistry, Lomonosov Moscow State University, 1-3 Leninskiye Gory, Moscow 119991, Russia.
| | - Serguei V Savilov
- Department of Chemistry, Lomonosov Moscow State University, 1-3 Leninskiye Gory, Moscow 119991, Russia.
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Shimpi MR, Rohlmann P, Shah FU, Glavatskih S, Antzutkin ON. Transition anionic complex in trihexyl(tetradecyl)phosphonium-bis(oxalato)borate ionic liquid - revisited. Phys Chem Chem Phys 2021; 23:6190-6203. [PMID: 33687391 DOI: 10.1039/d0cp05845a] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
It was found that Li[BOB]·nH2O salts were not readily suitable for the synthesis of high-purity orthoborate-based tetraalkylphosphonium ionic liquids, as exemplified here for trihexyl(tetradecyl)phosphonium bis(oxalato)borate, [P6,6,6,14][BOB]; along with [BOB]-, a metastable transition anionic complex (TAC) of dihydroxy(oxalato)borate with oxalic acid, [B(C2O4)(OH)2·(HOOC-COOH)]-, was also formed and passed into the ionic liquid in the course of the metathesis reaction with trihexyl(tetradecyl)phosphonium chloride. On the contrary, Na[BOB] was found to be a more suitable reagent for the synthesis of this IL, because [BOB]- anions safely passed into the final IL without hydrolysis, when metathesis reactions were performed using aqueous-free media. Since ultra-pure Na[BOB] is not commercially available, in this work, a preparation protocol for ultra-pure (>99%) Na[BOB] was developed: (i) molar ratios of boric and oxalic acids were optimised to minimise boron-containing impurities, (ii) the Na[BOB] product was thoroughly purified by sequential washing of a fine powder product in hot acetonitrile and ethanol and (iii) characterised using powder X-ray diffraction and solid-state 11B MAS NMR spectroscopy. The physico-chemical properties of the prepared boron-impurity-free IL, i.e., its density, viscosity, electric conductivity, glass-transition temperature and thermal stability, were found to be significantly different from those of the previously reported [P6,6,6,14][BOB], containing ca. 45 mol% of TAC, [B(C2O4)(OH)2·(HOOC-COOH)]-. It was found that a high-purity [P6,6,6,14][BOB] prepared in this work has a considerably lower viscosity, a higher viscosity index and a wider electro-chemical window (ECW) compared to those of the sample of [P6,6,6,14][BOB] with ca. 45 mol% of TAC. Interestingly, [B(C2O4)(OH)2·(HOOC-COOH)]- in the latter sample almost completely transformed into [BOB]- anions upon heating of the IL sample at 413 K for 1 hour, as confirmed using both 11B and 13C NMR. Therefore, in this work, apart from a well-optimised synthetic protocol for boron-impurity-free [P6,6,6,14][BOB], implications of boron-containing transition anionic complexes in tetraalkylphosphonium-orthoborate ILs used in different applications were highlighted.
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Affiliation(s)
- Manishkumar R Shimpi
- Chemistry of Interfaces, Luleå University of Technology, SE-97 187, Luleå, Sweden.
| | - Patrick Rohlmann
- System and Component Design, KTH Royal Institute of Technology, SE-10 044 Stockholm, Sweden
| | - Faiz Ullah Shah
- Chemistry of Interfaces, Luleå University of Technology, SE-97 187, Luleå, Sweden.
| | - Sergei Glavatskih
- System and Component Design, KTH Royal Institute of Technology, SE-10 044 Stockholm, Sweden and School of Chemistry, University of New South Wales, UNSW Sydney NSW 2052, Australia and Department of Electromechanical, Systems and Metal Engineering, Ghent University, B-9052 Ghent, Belgium
| | - Oleg N Antzutkin
- Chemistry of Interfaces, Luleå University of Technology, SE-97 187, Luleå, Sweden. and Department of Physics, Warwick University, CV4 7AL, Covertly, UK
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8
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Wu J, Liu W, Zhu R, Zhu X. On-line separation/analysis of Rhodamine B dye based on a solid-phase extraction high performance liquid chromatography self-designed device. RSC Adv 2021; 11:8255-8263. [PMID: 35423288 PMCID: PMC8695180 DOI: 10.1039/d0ra10771a] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/23/2020] [Accepted: 02/15/2021] [Indexed: 01/13/2023] Open
Abstract
A special self-designed device based on poly-1-vinyl-3-pentylimidazole hexafluorophosphate (PILs-C5) solid-phase extraction and high performance liquid chromatography (HPLC) is proposed as a novel method for the on-line separation and analysis of Rhodamine B (RhB) dye. Single factor experiment design and orthogonal experiment design were used to optimize the experimental parameters, such as pH, the amount of PILs-C5, sample volume, flow rate, eluent type, eluent concentration, eluent volume, and the flow rate of eluent. Under the optimized conditions, the linear range was 0.02-2.4 μg mL-1, with the correlation coefficients (R 2) of 0.997. The limit of detection (LOD) and limit of quantification (LOQ) were 0.004 μg mL-1 and 0.02 μg mL-1, respectively. The extraction capacity was 6.22 mg g-1, and enrichment ratio was 15. The extraction mechanism and the post-treatment method of PILs-C5 were also studied. This method was applied to analyze RhB in a wide variety of real samples with satisfactory results.
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Affiliation(s)
- Jun Wu
- College of Chemistry & Chemical Engineering, Yangzhou University Yangzhou 225002 PR China
| | - Wei Liu
- College of Chemistry & Chemical Engineering, Yangzhou University Yangzhou 225002 PR China
| | - Rui Zhu
- College of Guangling, Yangzhou University Yangzhou 225002 PR China
| | - Xiashi Zhu
- College of Chemistry & Chemical Engineering, Yangzhou University Yangzhou 225002 PR China
- College of Guangling, Yangzhou University Yangzhou 225002 PR China
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9
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Ionic liquids for regulating biocatalytic process: Achievements and perspectives. Biotechnol Adv 2021; 51:107702. [PMID: 33515671 DOI: 10.1016/j.biotechadv.2021.107702] [Citation(s) in RCA: 25] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/05/2020] [Revised: 12/26/2020] [Accepted: 01/15/2021] [Indexed: 12/26/2022]
Abstract
Biocatalysis has found enormous applications in sorts of fields as an alternative to chemical catalysis. In the pursue of green and sustainable chemistry, ionic liquids (ILs) have been considered as promising reaction media for biocatalysis, owing to their unique characteristics, such as nonvolatility, inflammability and tunable properties as regards polarity and water miscibility behavior, compared to organic solvents. In recent years, great developments have been achieved in respects to biocatalysis in ILs, especially for preparing various chemicals. This review tends to give illustrative examples with a focus on representative chemicals production by biocatalyst in ILs and elucidate the possible mechanism in such systems. It also discusses how to regulate the catalytic efficiency from several aspects and finally provides an outlook on the opportunities to broaden biocatalysis in ILs.
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Kontham V, Padmaja KV, Madhu D. Synthesis of ricinoleate anion based ionic liquids and their application as green lubricating oil additives. JOURNAL OF SAUDI CHEMICAL SOCIETY 2020. [DOI: 10.1016/j.jscs.2020.08.003] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
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11
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Wang YL, Li B, Sarman S, Mocci F, Lu ZY, Yuan J, Laaksonen A, Fayer MD. Microstructural and Dynamical Heterogeneities in Ionic Liquids. Chem Rev 2020; 120:5798-5877. [PMID: 32292036 PMCID: PMC7349628 DOI: 10.1021/acs.chemrev.9b00693] [Citation(s) in RCA: 192] [Impact Index Per Article: 48.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/29/2019] [Indexed: 12/11/2022]
Abstract
Ionic liquids (ILs) are a special category of molten salts solely composed of ions with varied molecular symmetry and charge delocalization. The versatility in combining varied cation-anion moieties and in functionalizing ions with different atoms and molecular groups contributes to their peculiar interactions ranging from weak isotropic associations to strong, specific, and anisotropic forces. A delicate interplay among intra- and intermolecular interactions facilitates the formation of heterogeneous microstructures and liquid morphologies, which further contributes to their striking dynamical properties. Microstructural and dynamical heterogeneities of ILs lead to their multifaceted properties described by an inherent designer feature, which makes ILs important candidates for novel solvents, electrolytes, and functional materials in academia and industrial applications. Due to a massive number of combinations of ion pairs with ion species having distinct molecular structures and IL mixtures containing varied molecular solvents, a comprehensive understanding of their hierarchical structural and dynamical quantities is of great significance for a rational selection of ILs with appropriate properties and thereafter advancing their macroscopic functionalities in applications. In this review, we comprehensively trace recent advances in understanding delicate interplay of strong and weak interactions that underpin their complex phase behaviors with a particular emphasis on understanding heterogeneous microstructures and dynamics of ILs in bulk liquids, in mixtures with cosolvents, and in interfacial regions.
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Affiliation(s)
- Yong-Lei Wang
- Department
of Materials and Environmental Chemistry, Arrhenius Laboratory, Stockholm University, SE-106 91 Stockholm, Sweden
| | - Bin Li
- School
of Chemical Engineering and Technology, Sun Yat-sen University, Zhuhai 519082, P. R. China
| | - Sten Sarman
- Department
of Materials and Environmental Chemistry, Arrhenius Laboratory, Stockholm University, SE-106 91 Stockholm, Sweden
| | - Francesca Mocci
- Department
of Chemical and Geological Sciences, University
of Cagliari, I-09042 Monserrato, Italy
| | - Zhong-Yuan Lu
- State
Key Laboratory of Supramolecular Structure and Materials, Institute
of Theoretical Chemistry, Jilin University, Changchun 130021, P. R. China
| | - Jiayin Yuan
- Department
of Materials and Environmental Chemistry, Arrhenius Laboratory, Stockholm University, SE-106 91 Stockholm, Sweden
| | - Aatto Laaksonen
- Department
of Materials and Environmental Chemistry, Arrhenius Laboratory, Stockholm University, SE-106 91 Stockholm, Sweden
- State
Key Laboratory of Materials-Oriented and Chemical Engineering, Nanjing Tech University, Nanjing 210009, P. R. China
- Centre of
Advanced Research in Bionanoconjugates and Biopolymers, Petru Poni Institute of Macromolecular Chemistry Aleea Grigore Ghica-Voda, 41A, 700487 Iasi, Romania
- Department
of Engineering Sciences and Mathematics, Division of Energy Science, Luleå University of Technology, SE-97187 Luleå, Sweden
| | - Michael D. Fayer
- Department
of Chemistry, Stanford University, Stanford, California 94305, United States
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12
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Rezaeian M, Izadyar M, Housaindokht MR. Thermal decomposition mechanisms of some amino acid ionic liquids: Molecular approach. J Mol Liq 2020. [DOI: 10.1016/j.molliq.2020.112505] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
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13
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Cai M, Yu Q, Liu W, Zhou F. Ionic liquid lubricants: when chemistry meets tribology. Chem Soc Rev 2020; 49:7753-7818. [PMID: 33135717 DOI: 10.1039/d0cs00126k] [Citation(s) in RCA: 70] [Impact Index Per Article: 17.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
Ionic liquids (ILs) have emerged as potential lubricants in 2001. Subsequently, there has been tremendous research interest in ILs from the tribology society since their discovery as novel synthetic lubricating materials. This also expands the research area of ILs. Consistent with the requirement of searching for alternative and eco-friendly lubricants, IL lubrication will experience further development in the coming years. Herein, we review the research progress of IL lubricants. Generally, the tribological properties of IL lubricants as lubricating oils, additives and thin films are reviewed in detail and their lubrication mechanisms discussed. Considering their actual applications, the flexible design of ILs allows the synthesis of task-specific and tribologically interesting ILs to overcome the drawbacks of the application of ILs, such as high cost, poor compatibility with traditional oils, thermal oxidization and corrosion. Nowadays, increasing research is focused on halogen-free ILs, green ILs, synthesis-free ILs and functional ILs. In addition to their macroscopic properties, the nanoscopic performance of ILs on a small scale and in small gaps is also important in revealing their tribological mechanisms. It has been shown that when sliding surfaces are compressed, in comparison with a less polar molecular lubricant, ion pairs resist "squeeze out" due to the strong interaction between the ions of ILs and oppositely charged surfaces, resulting in a film that remains in place at higher shear forces. Thus, the lubricity of ILs can be externally controlled in situ by applying electric potentials. In summary, ILs demonstrate sufficient design versatility as a type of model lubricant for meeting the requirements of mechanical engineering. Accordingly, their perspectives and future development are discussed in this review.
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Affiliation(s)
- Meirong Cai
- State Key Laboratory of Solid Lubrication, Lanzhou Institute of Chemical Physics, Chinese Academy of Sciences, Lanzhou 730000, China.
| | - Qiangliang Yu
- State Key Laboratory of Solid Lubrication, Lanzhou Institute of Chemical Physics, Chinese Academy of Sciences, Lanzhou 730000, China.
| | - Weimin Liu
- State Key Laboratory of Solid Lubrication, Lanzhou Institute of Chemical Physics, Chinese Academy of Sciences, Lanzhou 730000, China. and State Key Laboratory of Solidification Processing, College of Materials Science and Technology, Northwestern Polytechnical University, 127 YouyiXi Road, Xi an 710072, China
| | - Feng Zhou
- State Key Laboratory of Solid Lubrication, Lanzhou Institute of Chemical Physics, Chinese Academy of Sciences, Lanzhou 730000, China.
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Rohlmann P, Munavirov B, Furó I, Antzutkin O, Rutland MW, Glavatskih S. Non-halogenated Ionic Liquid Dramatically Enhances Tribological Performance of Biodegradable Oils. Front Chem 2019; 7:98. [PMID: 30891442 PMCID: PMC6413702 DOI: 10.3389/fchem.2019.00098] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/08/2018] [Accepted: 02/05/2019] [Indexed: 11/13/2022] Open
Abstract
It is demonstrated that a phosphonium orthoborate ionic liquid may serve as a wear reducing additive in biodegradable oils at steel-steel surfaces in the boundary lubrication regime. Tribological tests were performed in a ball-on-three plate configuration. A set of surface characterization techniques—SEM/EDS, FIB and white light interferometry were used to characterize surfaces following the tribotests and to observe the formation of any tribofilms. 11B NMR was used to follow changes in the composition of the ionic-liquid-oil blends and to identify boron-containing decomposition products after the tribotests. The ionic liquid reduces the wear of steel surfaces by up to 92% compared to the neat oil at 90°C; it is shown that the reduction in wear can be correlated with the formation of boron enriched patches in the boundary films.
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Affiliation(s)
- Patrick Rohlmann
- Machine Design, KTH Royal Institute of Technology, Stockholm, Sweden
| | - Bulat Munavirov
- Machine Design, KTH Royal Institute of Technology, Stockholm, Sweden
| | - István Furó
- Department of Chemistry, KTH Royal Institute of Technology, Stockholm, Sweden
| | - Oleg Antzutkin
- Chemistry of Interfaces, Luleå University of Technology, Luleå, Sweden
| | - Mark William Rutland
- Department of Chemistry, KTH Royal Institute of Technology, Stockholm, Sweden.,Surfaces, Processes and Formulation, RISE Research Institutes of Sweden, Stockholm, Sweden
| | - Sergei Glavatskih
- Machine Design, KTH Royal Institute of Technology, Stockholm, Sweden.,Department of Electrical Energy, Metals, Mechanical Constructions and Systems, Ghent University, Ghent, Belgium
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Filippov A, Azancheev N, Gibaydullin A, Bhattacharyya S, Antzutkin ON, Shah FU. Dynamic properties of imidazolium orthoborate ionic liquids mixed with polyethylene glycol studied by NMR diffusometry and impedance spectroscopy. MAGNETIC RESONANCE IN CHEMISTRY : MRC 2018; 56:113-119. [PMID: 28752526 DOI: 10.1002/mrc.4636] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/01/2017] [Accepted: 07/21/2017] [Indexed: 06/07/2023]
Abstract
We used 1 H pulsed field gradient nuclear magnetic resonance to study the self-diffusion of polyethylene glycol (PEG) with average molecular mass of 200 and ions in mixtures of PEG with imidazolium bis(mandelato)borate (BMB) and imidazolium bis(oxalato)borate ionic liquids (ILs). The IL was mixed with PEG in the concentration range of 0-100 wt%. Within the temperature range of 295 to 353 K, the diffusion coefficient of BMB is slower than that of the imidazolium cation. The diffusion coefficients of PEG, as well as the imidazolium cation and BMB anions, differ under all experimental conditions tested. This demonstrates that the IL in the mixture is present in at least a partially dissociated state. Generally, increasing the concentration of PEG leads to an increase in the diffusion coefficients of PEG and both the ions and decreases their activation energy for diffusion. Nuclear magnetic resonance chemical shift alteration analysis showed that the presence of PEG changes the chemical shifts of both ions but in different directions. Impedance spectroscopy was used to measure the ionic conductivity of the ILs mixed with PEG. Copyright © 2017 John Wiley & Sons, Ltd.
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Affiliation(s)
- Andrei Filippov
- Chemistry of Interfaces, Luleå University of Technology, Luleå, SE-91187, Sweden
- Physics of Molecular Systems, Institute of Physics, Kazan Federal University, Kazan, 420008, Russia
| | - Nail Azancheev
- Physics of Molecular Systems, Institute of Physics, Kazan Federal University, Kazan, 420008, Russia
| | - Amal Gibaydullin
- Physics of Molecular Systems, Institute of Physics, Kazan Federal University, Kazan, 420008, Russia
| | | | - Oleg N Antzutkin
- Chemistry of Interfaces, Luleå University of Technology, Luleå, SE-91187, Sweden
| | - Faiz Ullah Shah
- Chemistry of Interfaces, Luleå University of Technology, Luleå, SE-91187, Sweden
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16
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Wang YL, Golets M, Li B, Sarman S, Laaksonen A. Interfacial Structures of Trihexyltetradecylphosphonium-bis(mandelato)borate Ionic Liquid Confined between Gold Electrodes. ACS APPLIED MATERIALS & INTERFACES 2017; 9:4976-4987. [PMID: 28099800 DOI: 10.1021/acsami.6b14429] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/06/2023]
Abstract
Atomistic molecular dynamics simulations have been performed to study microscopic the interfacial ionic structures, molecular arrangements, and orientational preferences of trihexyltetradecylphosphonium-bis(mandelato)borate ([P6,6,6,14][BMB]) ionic liquid confined between neutral and charged gold electrodes. It was found that both [P6,6,6,14] cations and [BMB] anions are coabsorbed onto neutral electrodes at different temperatures. The hexyl and tetradecyl chains in [P6,6,6,14] cations lie preferentially flat on neutral electrodes. The oxalato and phenyl rings in [BMB] anions are characterized by alternative parallel-perpendicular orientations in the mixed innermost ionic layer adjacent to neutral electrodes. An increase in temperature has a marginal effect on the interfacial ionic structures and molecular orientations of [P6,6,6,14][BMB] ionic species in a confined environment. Electrifying gold electrodes leads to peculiar changes in the interfacial ionic structures and molecular orientational arrangements of [P6,6,6,14] cations and [BMB] anions in negatively and positively charged gold electrodes, respectively. As surface charge density increases (but lower than 20 μC/cm2), the layer thickness of the mixed innermost interfacial layer gradually increases due to a consecutive accumulation of [P6,6,6,14] cations and [BMB] anions at negatively and positively charged electrodes, respectively, before the formation of distinct cationic and anionic innermost layers. Meanwhile, the molecular orientations of two oxalato rings in the same [BMB] anions change gradually from a parallel-perpendicular feature to being partially characterized by a tilted arrangement at an angle of 45° from the electrodes and finally to a dominant parallel coordination pattern along positively charged electrodes. Distinctive interfacial distribution patterns are also observed accordingly for phenyl rings that are directly connected to neighboring oxalato rings in [BMB] anions.
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Affiliation(s)
- Yong-Lei Wang
- Department of Materials and Environmental Chemistry, Arrhenius Laboratory, Stockholm University , SE-106 91 Stockholm, Sweden
| | - Mikhail Golets
- Department of Materials and Environmental Chemistry, Arrhenius Laboratory, Stockholm University , SE-106 91 Stockholm, Sweden
| | - Bin Li
- Theoretical Chemistry, Chemical Center, Lund University , P.O. Box 124, SE-221 00 Lund, Sweden
| | - Sten Sarman
- Department of Materials and Environmental Chemistry, Arrhenius Laboratory, Stockholm University , SE-106 91 Stockholm, Sweden
| | - Aatto Laaksonen
- Department of Materials and Environmental Chemistry, Arrhenius Laboratory, Stockholm University , SE-106 91 Stockholm, Sweden
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17
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Gusain R, Bakshi PS, Panda S, Sharma OP, Gardas R, Khatri OP. Physicochemical and tribophysical properties of trioctylalkylammonium bis(salicylato)borate (N888n-BScB) ionic liquids: effect of alkyl chain length. Phys Chem Chem Phys 2017; 19:6433-6442. [DOI: 10.1039/c6cp05990b] [Citation(s) in RCA: 40] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
Abstract
The alkyl chain length in trioctylalkylammonium bis(salicylato)borate ionic liquids plays an important role in controlling the viscosity, friction and wear characteristics.
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Affiliation(s)
- Rashi Gusain
- Chemical Science Division
- CSIR-Indian Institute of Petroleum
- Dehradun – 248005
- India
| | - Paramjeet S. Bakshi
- Chemical Science Division
- CSIR-Indian Institute of Petroleum
- Dehradun – 248005
- India
| | - Somenath Panda
- Department of Chemistry
- Indian Institute of Technology Madras
- Chennai – 600036
- India
| | - Om P. Sharma
- Chemical Science Division
- CSIR-Indian Institute of Petroleum
- Dehradun – 248005
- India
| | - Ramesh Gardas
- Department of Chemistry
- Indian Institute of Technology Madras
- Chennai – 600036
- India
| | - Om P. Khatri
- Chemical Science Division
- CSIR-Indian Institute of Petroleum
- Dehradun – 248005
- India
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