PART 1: Proposal Identification
Title of Proposal: Carbon nanofoam for battery and supercapacitor applications
Project Theme Title: Next Generation Battery
Project Subject Title: High Efficient Supercapacitor, High Efficient Material for Electro-Chemical Electrodes
Dmitrii Zherebtcov, Damir Galimov
Affiliation: South Ural State University
Department1: Chair of Physical Chemistry,
Department2: Scientific-Educational Center “Nanotechnology”
Postal Address: pr. Lenina, 76, Chelyabinsk, 454080,
Phone: +7 908 0425307
PART 2: Project Summary
- Announcement of Multi-year Proposal
We propose three year research, and specific plan for this year will be described in this proposal.
- Research Abstracts and Goals
Main goal is development of new method of production of carbon nanofoam as versatile electrode material for electrochemical applications like supercapacitors, battery electrodes, fuel cell electrodes, chemical sensors. Material could also be used in high-frequency electronics having a dielectric constant less than 1.3 at 10MHz (preliminary results).
Another goal is evaluation of the effect of synthesis conditions on the structure and physical properties of the resulting carbon nanofoam.
Microemulsions in ternary systems with surfactants such as “water-oil-surfactant” have a complex bicontinuous morphology and are thermodynamically stable to phase separation of the hydrophobic and hydrophilic microphase.
Microemulsions with polymers obtained through polymerization of the monomer-surfactant-solvent solution are attracting special attention. Thus, using a furfuryl alcohol as a monomer, a nonionic surfactant and the organic solvent we have obtained polymer bicontinuous microemulsions which have been transformed by calcination into carbon nanofoam having a specific surface area 300-1000 m2/g. The source of carbon is a furan polymer capable on calcination to convert into carbon with a high yield of 65 %. Introduction of different concentrations of surfactant and solvent into furfuryl alcohol creates conditions for formation of the various micro- and nanostructures in a solution.
The resulting carbon nanofoam is a unique material, the structure and properties of which can be set and varied widely by synthesis conditions (furfuryl alcohol, nonionic surfactant and organic solvent ratio).
Its special features include a bimodal porosity, centered in the range of 1-20 and 500-3000 nm with a homogeneous pore size distribution and shape (preliminary results). Such nanostructured material has a number of new features: low density, high thermal insulation, high surface area, high specific mechanical strength, high adsorption and permeability to gases and liquids, anomalous dielectric constant, still having electrical conductivity and chemical inertness. Behind supercapacitors, battery electrodes, fuel cell electrodes and chemical sensors the carbon nanofoam able to find use as functional nanomaterial for adsorbents and membranes, catalyst support, material for high-frequency electronics. Developed approach to the synthesis of carbon nanofoam is unique and stays ahead of the world competitors. Mechanisms of formation of polymer in microemulsions, of their thermolysis, and the dependence of the structure and properties of the resulting carbon nanofoam on the composition of the starting solution and the conditions of their processing are still almost unknown.
- One or two keywords that best capture the principal focus of proposed research: carbon nanofoam.
PART 3: Description of Project
- Project Duration (01/09/2015 ~ 31/08/2018)
- Research Objectives
To achieve the main goal it will be performed investigation of the mechanism of formation and thermolysis of the furfural polymer solution.
Resulted carbon nanofoam materials will be carefully analyzed by numerous methods.
The proposed work will validate influence of surfactant and solvent as regulators of, respectively, macro- and nanoporosity of carbon nanofoam. That will be a base for development of new class carbon nanofoams with tunable properties.
- Significance of Research
Currently there is need in electrode material having bimodal porosity, centered in the range of 0.5-5 and 200-5000 nm with a homogeneous pore size distribution and shape. Such nanostructured material should have multiple features: high surface area, high adsorption and permeability to gases and liquids, electrical conductivity, chemical inertness, high specific mechanical strength, low density, low dielectric constant.
Carbon nanofoam is best suited for this application.
Alternative approaches known from literature:
- Substance called carbon nanofoam was obtained in 1999  by laser evaporation of dense glassy carbon target. Thus carbon source was vaporized and then deposited on the substrate surface in a form a porous layer. This material attracted attention due to abnormally high magnetic susceptibility [2-4] and other physical properties. Unfortunately, laser method produces only small amounts of carbon nanofoam, having inhomogeneous morphology and properties. It also technically complicated method.
- Another carbon materials were prepared in complex way, by impregnating of silica gel with a solution of a polymer with a subsequent thermolysis of polymer into glassy carbon, followed by washing with concentrated hydrofluoric acid . Instead of silica gel it can be used materials such as silica based mesoporous MCM- 41. The morphology of the resulting carbon material in this case is more uniform than material after laser evaporation, however, 1) morphology of the carbon nanofoam is a replica from silica matrix (so, method have less flexible control on morphology); 2) impregnation of silica matrix occurs in a relatively thin layer that limits the size, shape and uniformity of the carbon material, 3) the multistep preparation process is difficult and involve the use of large amounts of toxic hydrofluoric acid.
- Should be mentioned the original method of preparing of nanoporous carbon through synthesis of unique block copolymers [6, 7]. In this method, the structural motif specifies the size and type of block copolymer, e.g., polyisoprene – block – polydimethylaminoethylmethacrylate or polyacrylonitrile – block – polyethyleneoxide – block – polypropyleneoxide. On pyrolysis of the block copolymer, one block decomposes to form carbon residue and the other is completely decomposed into volatile products, creating pores. However, this method requires complex and costly steps of the synthesis of the block copolymer (not commercially available).
Abovementioned approaches leaded by following groups:
- Professor Andrei V. Rode, Australian National University, Australia.
- Professor Yong-Yao Xia, Fudan University, China.
- Professor Ulrich Wiesner, Cornell University, USA.
In 2010-2014 we tested method for synthesis of nanoporous glassy carbon materials (carbon nanofoam) on several samples, including the thermolysis of polymers (furan resins) modified with surfactant and organic solvent. Role of pore generator instead of expensive block copolymer played surfactant and the solvent. The result is a nanoporous solid body. It formed by droplets of foam bonded to each other by bridges into three dimensional grid with macropores of 1-3 microns. That provides fast access into the material of gas molecules and fluids. Such organization of the material gives it a number of new properties: low density, high strength and elasticity, high gas permeability, developed pore surface area, high adsorption capacity. A unique feature of the new materials is the uniform size distribution and shape of micro- and nano-pores.
It was found that ratio of components on synthesis govern the size of these pores, and physical properties of the material.
The ability to produce three-dimensional block of material samples (20x30x30 mm) facilitates its further investigation. In 2011, 3 samples of our materials were sent to the Lappeenranta University of Technology (Finland) to measure their magnetic properties. The results were presented at international conferences [8, 9] and in article .
It is shown that the morphology of new material determines its high elasticity . The ternary phase diagram of related system of furfuryl alcohol -surfactant – water was also reported .
To understand way to get said morphology and related physical properties of carbon nanofoam it is needed to study the mechanism of polymerization in the ternary system furfuryl alcohol -surfactant – triethyleneglycol.
- A. Rode, B. Luther-Davies, E. Gamaly. Ultrafast Ablation with High-Pulse-Rate Lasers. Part II: Experiments on Laser Deposition of Amorphous Carbon Films. Journal of Applied Physics. 1999. vol.85. pp.4222-4230.
- A.V. Rode, R.G. Elliman, E.G. Gamaly, A.I. Veinger, A.G. Christy, S.T. Hyde, B. Luther-Davies. Electronic and magnetic properties of carbon nanofoam produced by high-repetition-rate laser ablation. Applied Surface Science. 2002. vol.197. pp.644-699.
- A. V. Rode, E. G. Gamaly, A. G. Christy, J. G. Fitz Gerald, S. T. Hyde, R. G. Elliman, B. Luther-Davies, A. I. Veinger, J. Androulakis, J. Giapintzakis. Unconventional Magnetism in All-Carbon Nanofoam. Physical Review B: Condensed Matter and Materials. 2004. vol.70. no.5. pp.054407-1-9.
- T. Makarova, F. Palacio (editors). Carbon Based Materials. North-Holland, Elsevier (2006).
- H.-Q. Li, R.-L. Liu, D.-Y. Zhao, Y.-Y. Xia. Electrochemical properties of an ordered mesoporous carbon prepared by direct tri-constituent co-assembly. Carbon. 2007. 45(13) 2628-2635
- S.C. Warren, L.C. Messina, L.S. Slaughter, M. Kamperman, Q. Zhou, S.M. Gruner, F.J. DiSalvo, U. Wiesner. Ordered Mesoporous Materials from Metal Nanoparticle-Block Copolymer Self-Assembly. Science. 320. (2008) 1748-1752.
- M. Stefik, H. Sai, K. Sauer, S.M. Gruner, F.J. DiSalvo, U. Wiesner. Three-Component Porous-Carbon-Titania Nanocomposites through Self-Assembly of ABCBA Block Terpolymers with Titania Sols. Macromolecules. 42. 2009. 6682–6687.
- E. Lahderanta, A.V. Lashkul, K.G. Lisunov, A. Pulkkinen, D.A. Zherebtsov, D.M. Galimov, A.N. Titkov. Irreversible Magnetic Properties of Nanocarbon. NANOSMAT Conference. Krakow. 2011. Р.1-22.
- E. Lahderanta, A.V. Lashkul, K.G. Lisunov, D.A. Zherebtsov, D.M. Galimov, A.N. Titkov. Magnetic Properties of Carbon Nanoparticles. International Conference on Functional Materials and Nanotechnologies (FM&NT2012). Riga, University of Latvia. IOP Conf. Series: Materials Science and Engineering, 38. 2012. P.012010.
- E. Lahderanta, A.V. Lashkul, K.G. Lisunov, D.A. Zherebtsov, D.M. Galimov, A.N. Titkov. Irreversible Magnetic properties of Nanocarbon. Journal of Nanoscience and Nanotechnology. V.12(12) 2012. P.9156-9162.
- Д.А. Жеребцов, С.Б. Сапожников, Д.М. Галимов. Эластичный стеклоуглеродный материал с высокой удельной поверхностью. Перспективные материалы. № 6. 2012. С.87-89.
- D.A. Zherebtsov. Properties of Solutions Formed by Water, Furfuryl Alcohol, and Poly(Ethylene Glycol) (10) Isooctyl Phenol Ether. Russian Journal of Applied Chemistry, 2012, Vol. 85, No. 4, pp. 584−588.
- Research Plan and Technical Approach
To get the goal it will be synthesized 27 samples in the system furfuryl alcohol – surfactant – triethyleneglycol (TEG). During the synthesis the properties of solutions will be measured during the polymerization (viscosity, conductivity and size of polymer macromolecules by dynamic light scattering) and subsequent thermolysis (linear shrinkage, electrical conductivity, thermogravimetric analysis and differential scanning calorimetry analysis with the mass spectrometry of emitted gas). Will be examined physical properties of the resulted carbon nanofoam (density, porosity, adsorption properties, the specific surface area, the hardness, compressive strength, electrical conductivity, the structure and morphology by scanning electron microscopy and powder X-ray diffraction).
Preparation of 27 solutions furfuryl alcohol – surfactant – TEG.
Synthesis will be carried out on samples of a ternary diagram, wherein the furfuryl alcohol content will be in the range of 25 to 35 wt. % (that corresponds to the final highly porous carbon nanofoam), and the content of surfactant and solvent will vary from 0 to 75 wt. % (that will reveal the effect of each component on the properties of the solutions, the mechanism of polymerization and the morphology, structure and properties of the resulting carbon nanofoam).
For research it will be used 50 g of solutions that will provide enough material for all further measurements.
The results of measurement of the viscosity, conductivity, refractive index of the solutions will reveal the dependence of these structure-sensitive properties on the composition of the solutions, evaluate the degree of interaction between components.
Measurements of the properties of the solutions will allow to identify region on ternary system in which the interaction is strongest, and in which the characteristics can be expected in the structure in solution and subsequent polymerization mechanism.
After investigating the properties of these solutions it will be added a small amount of hydrochloric acid (catalyzing polymerization) sufficient to polymerize it within 1-2 weeks. To prevent changes in the composition of samples, it will be conducted in a sealed vessels opened periodically for measurements.
Measurements of viscosity, conductivity as well as measurements of size of the macromolecules in the polymer suspension by dynamic light scattering will be carried out at intervals of a few hours (at the initial period of polymerization) to several days (at a final period of polymerization) until the formation of the polymer gel. As in the previous step, results of measurement of viscosity and conductivity of the solution during the polymerization reaction will reveal structure-sensitive properties dependence on the composition of the solutions. The results of measuring the size of macromolecules give additional opportunity to highlight the contributions to the change in viscosity and electrical conductivity of different phenomena: the growth length of the macromolecules, water and furfuryl alcohol concentration change, formation of microemulsion (microphase separation), cross-linking of the polymer molecules. On the series of two solutions it will be investigated NMR spectra to determine the kinetics of furfuryl alcohol spending. Thus, processes of catalytic polymerization in ternary solutions will be disclosed.
Next step of polymerization will be completed by heating samples at 50, 100, 150 °C for 2 days.
After completion of the polymerization it will be carried out thermolysis of samples in an oxygen-free samples atmosphere by slow heating to 900 °C. To study thermolysis of the polymer it will be additionally prepared sample solution filled and polymerized in the original glass cell with carbon electrodes, allowing during the slow heating to 900 ° C continuously measure the conductivity of the sample. This will resolve the steps of elimination of volatile thermolysis product (H2O, CO2), and crosslinking of the polymer chains. For a detailed study on the thermolysis of 2 samples will be held simultaneous thermal analysis (thermogravimetry and differential scanning calorimetry) with the analysis of the mass spectrum of gases evolved. Measurements will be carried out under argon atmosphere and provide thermal effects on thermolysis and mass loss, as well as the composition of the volatile components released from the sample. In combination with conductivity measurement of the sample during heating it will allow to understand the mechanism of thermolysis.
After heat treatment it will be obtained 27 carbon nanofoam samples. Measurement of linear shrinkage upon thermolysis of the polymer will assess the strength of spatial grid of polymer drops during syneresis. This quantity is associated with the pore size of the droplets and the polymer, as well as their strength. Droplet size will be measured after the formation of carbon nanofoam by scanning electron microscopy, so the impact of droplet strength can be assessed from linear shrinkage.
27 samples of carbon nanofoam will be cut into rectangular plates 10x10x3 mm. Their physical properties (density, porosity, adsorption properties, the specific surface area, microhardness, compressive strength, conductivity, dielectric constant) as well as the structure and morphology by electron microscopy and powder X-ray diffraction to be investigated. All these properties are structure-sensitive and will confirm each other.
Say, pycnometric density is associated with open and closed porosity and open porosity – with adsorption properties and surface area. Their measurement will be confirmed by electron microscopic observation of the size of droplets and pores.
The compressive strength is related to the size of the droplets of the carbon nanofoam, and to their structure. Microhardness is closely related with the strength, confirming its data, as well as the degree of homogeneity of carbon nanofoam.
Carbon nanofoam can include both – fragments of the graphene sheet (high strength and anisotropy) and fragments of the amorphous material with sp2 and sp3- hybridization of the carbon atoms (with isotropic mechanical properties). Ordering of graphene planes along the bridges connecting nanofoam drops significantly increases the strength of the material. Dielectric properties, conductivity, strength of graphenic and isotropic areas vary greatly, so the measured values will depend on the number of such areas and their orientation. Measurement will allow to resolve the contribution from both types of carbon and the dominance of one of them in the samples. In addition, powder X-ray structure analysis will reveal the presence or absence of graphite (in the case of multilayer graphene sheets). This conclusion will allow to understand the mechanism of synthesis and to recognize the influence of surfactant and solvent, respectively, as regulators of the formation of macro- and nanoporosity in carbon nanofoam.
Combining in a mathematical model composition and properties of 27 solutions by polymerization parameters and by properties of the resulting carbon nanofoam. This will allow to build a three-dimensional response surface of properties upon the composition of the initial three-component solutions. Knowledge of dependence of properties of carbon nanofoam upon the composition of the initial three-component solutions will allow creating materials with predetermined properties.
Writing of the final report and plan for the next year (synthesis of carbon nanofoam with a different solvent in three-component solution).
Month 1. 27 solutions furfuryl alcohol – surfactant – TEG, 50 g each. The results of measurement of the viscosity, conductivity, refractive index of the solutions.
Month 2. The results of measurement of viscosity, conductivity as well as measurements of size of the macromolecules in the polymer suspension by dynamic light scattering of 27 solutions.
Month 3. NMR spectra of series of two solutions to determine the kinetics of furfuryl alcohol spending. The results of polymerization kinetics. 27 completely polymerized samples.
Month 4. 27 samples after thermolysis at 900 °C. Results of conductivity measurement during the slow heating to 900 ° C.
Month 5. Results of simultaneous thermal analysis with the analysis of the mass spectrum of gases evolved of 2 samples.
Month 6. Results of linear shrinkage upon thermolysis of the polymer of 27 samples.
Month 7. 27 samples of carbon nanofoam cut into rectangular plates 10x10x3 mm. Results of measurement of structure and morphology by electron microscopy and powder X-ray diffraction of 27 samples of carbon nanofoam.
Month 8. Results of measurement of physical properties (microhardness, compressive strength, conductivity, dielectric constant) of 27 samples of carbon nanofoam.
Month 9. Results of measurement of physical properties (density, porosity, adsorption properties, the specific surface area) of 27 samples of carbon nanofoam.
Month 10. Table and mathematical models of properties of 27 solutions as function of its composition. Table and mathematical models of properties of 27 carbon nanofoam samples as function of starting solution composition.
Month 11. Application on patent with Samsung on novel method for production of carbon nanofoam.
Month 12. Final report and plan for the next year (synthesis of carbon nanofoam with a different solvent in three-component solution).
- Expected Outcomes and Results
- 27 samples of carbon nanofoam having new structure. Prototype samples will be prepared as plates 10x10x3 mm or bigger.
- Laboratory approved method for obtaining of carbon nanofoam. Method description.
- Dependence of the structure and morphology of carbon nanofoam on the conditions of its synthesis. Table and mathematical models.
- Dependence of the physical properties of carbon nanofoam on the conditions of its synthesis. Table and mathematical models.
PART 4: Budget
- Total Budget: CHF 100,000
Direct expenses CHF 90,000
Indirect costs (overhead) CHF 10,000
23 International publications:
- A. Zherebtsov, D.M. Galimov, V.V. Dyachuk, G.G. Mikhailov, D.A. Uchaev, and S.A. Sergeeva. One-Pot Synthesis of Anatase/Carbon Nanocomposite. J. Nanoelectron. Optoelectron. V.8 (2013) P.221-222.
- A. Zherebtsov, V.P. Sirkeli, F.J. DiSalvo, E. Lahderanta, K. Xu, A.V. Lashkul, R. Laiho, A.Yu. Bobylev, Z.L. Liu, D.A. Vinnik, D.M. Galimov, V.V. Dyachuk, V.G. Zakharov. Photoluminescence of flux grown GaN crystals. J. Nanoelectron. Optoelectron. V.8 (2013) P. 285-291.
- Krivtsov I.V., Ilkaeva M.V., Avdin V.V., Zherebtsov D.A.
Properties and segregation stability of the composite silica-zirconia xerogels prepared via “acidic” and “basic” precipitation routes.
Journal of Non-Crystalline Solids. V.362. (2013) 95-100.
- Pesin L.A., Morilova V.M., Zherebtsov D.A., Evsyukov S.E.
Kinetics of PVDF film degradation under electron bombardment.
Polymer Degradation and Stability. V.98. (2013) 666-670.
- Zhang, D.A. Zherebtsov, F.J. DiSalvo, R. Niewa. Na5[CN2]2[CN], (Li,Na)5[CN2]2[CN], and K2[CN2]: carbodiimides from high-pressure synthesis. Z. Anorg. Allg. Chemie. V.638 (2012) 2111-2116.
- V. Avdin, I.V. Krivtsov, V.V. Dyachuk, D.A. Zherebtsov. Thermal behavior of the composite xerogels of zirconium oxyhydroxide and silicic acid. J. Therm. Anal. Calorim. (2012) V.109. No.1. P1261-1265.
- Vinnik, D. Zherebtsov, S. Archugov, M. Bischoff, R. Niewa. Crystal Growth and Characterization of Alexandrite. Crystal Growth & Design. 2012. V.12, 3954−3956.
- Bräunling, O. Pecher, D.M. Trots, A. Senyshyn, D.A. Zherebtsov, F. Haarmann, R. Niewa. Synthesis, Crystal Structure and Lithium Motion of Li8SeN2 and Li8TeN2. Z. Anorg. Allg. Chem. 636. (2010) 936–946.
- Niewa, D.A. Zherebtsov. Comment on the Paper: Synthesis and Electrochemical Study of Antifluorite-type Phases in the Li-M-N-O (M = Ti, V) Systems. Z. Anorg. Allg. Chem. V.632(3) (2006) 387-388.
- Niewa, D.A. Zherebtsov. New phases in the lithiumnitridovanadate system – the solid solution Li7-2xMgx[VN4] with 0 < x < 1. Z. Anorg. Allg. Chemie (2004) 630(2) 229-233.
- Niewa, D.A. Zherebtsov, W. Schnelle, F.R. Wagner. Metal-Metal Bonding in ScTaN2. A New Compound in the System ScN-TaN. Inorganic Chemistry (2004) 43(20) 6188-6194.
- Niewa, D.A. Zherebtsov, M. Kirchner, M. Schmidt, W. Schnelle. New Ways to High-Quality Bulk Scandium Nitride. Chem. Mater., 2004, 16 (25), pp 5445–5451.
- Niewa, D.A. Zherebtsov, P. Hoehn. Crystal structure of tristrontium tetranitridochromate(VI), Sr3[CrN4]. Z. Kristallogr. NCS (2003) 218(2) 163.
- Niewa, D.A. Zherebtsov, Z. Hu. Polymorphism of Heptalithium Nitridovanadate(V) Li7[VN4]. Inorg. Chemistry (2003) 42(8) 2538-2544.
- Niewa, D.A. Zherebtsov, S. Leoni. Li3[ScN2]: The first nitridoscandate(III)-tetrahedral Sc coordination and unusual MX2 framework. Chemistry-A European Journal (2003) 9(17) 4255-4259.
- Niewa, D.A. Zherebtsov, R. Kniep. Zur Polymorphie von Li7[VN4]. Z. Anorg. Allg. Chem. 628(9-10) (2002) 2202.
- Niewa, D.A. Zherebtsov, H. Borrmann, R. Kniep. Preparation and Crystal Structure of Li4[TaN3]. Z. Anorg. Allg. Chem. 628 (2002) 2505-2508.
- Niewa, D.A. Zherebtsov. Redetermination of the crystal Structure of tetralithium nitride hydride, Li4NH. Z. Kristallogr. NCS 217 (2002) 317.
- A. Zherebtsov, L.G. Akselrud, R. Niewa. Crystal Structure of Dicalcium Trinitridomonovanadate (V), Ca2[VN3]. Z. Kristallogr. NCS (2002) 217(4) 469.
- A. Jerebtsov, G.G. Mikhailov, S.V. Sverdina. Phase diagram of the system: Al2O3-ZrO2. Ceramics International. V.26 N8. 2000 PP. 821-823.
- A. Jerebtsov, G.G. Mikhailov. Phase diagram of CaO–Al2O3 system. Ceramics International. V.27 N1. 2001 PP. 25-28.
- A. Jerebtsov, G.G. Mikhailov, S.V. Sverdina.Phase diagram of the system: ZrO2–Cr2O3. Ceramics International. V.27 N3. 2001 PP. 247-250.
- Lahderanta, A.V. Lashkul, K.G. Lisunov, D.A. Zherebtsov, D.M. Galimov, A.N. Titkov. Irreversible Magnetic properties of Nanocarbon. Journal of Nanoscience and Nanotechnology. 2012. V.12 P.9156-9162.
5 Russian patents on invention:
- Russian Patent 2444550. Priority: 4.05.2009. Method for titanium dioxide production. A. Zherebtsov, A.M. Kolmogortsev, A.S. Serikov, V.V. Viktorov.
- Russian Patent 2154297. Priority: 14.05.1999. Method for automatic regulation of furnace temperature. A. Zherebtsov, G.G. Mikhailov.
- Russian Patent 2164681. Priority: 29.06.1999. Measuring cell for differential thermal analysis unit. A. Zherebtsov, G.G. Mikhailov.
- Russian Patent 2477766. Priority: 22.09.2011. Gallium nitride single crystal growth method. A. Zherebtsov.
- Russian application for a patent for invention. Priority: 05.11.2013. The method of production for nanoporous carbon material. A. Zherebtsov, D.M. Galimov, S.B. Sapozhnikov.
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