(12) United States Patent (10) Patent No.: US 8,703,523 B1

Dec 5, 2011 — bon active channel may be saturated by the electrolyte in bon active channel based on an applied electrochemical potential, wherein the

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USOO8703523B1 (12) United States Patent (10) Patent No.: US 8,703,523 B1 Biener et al. (45) Date of Patent: Apr. 22, 2014 (54) NANOPOROUS CARBONTUNABLE 7,247.290 B2 7/2007 Lobovsky et al. RESISTOR/TRANSISTOR AND METHODS OF 250 5. R 358, W. et al, – W – eaver, Jr. PRODUCTION THEREOF 7,399.400 B2 7/2008 Soundarrajan et al. (75) Inventors: Juergen Biener, San Leandro, CA (US); (Continued) Theodore F. Baumann, Discovery Bay, CA (US); Subho Dasgupta FOREIGN PATENT DOCUMENTS Eggenstein-Leopoldshafen (DE); Horst EP 2236 824 A2 10, 2010 Hahn, Seeheim-Jugenheim (DE) WO O1,57917 A3 8, 2001 (73) Assignees: Lawrence Livermore National (Continued) Security, LLC., Livermore, CA (US); OTHER PUBLICATIONS Karlsruher Institut fur Technologie (KIT), Eggenstein-Leopoldshafen (DE) Pribat et al., fiLateral alumina templates for carbon nanotubes and semiconductor nanowires synthesis.fl 2005, M. Razeghi and G. J. (*) Notice: Subject to any disclaimer, the term of this Brown, Quantum Sensing and Nanophotonic Devices II, Proeedings patent is extended or adjusted under 35 of SPIE, vol. 5732, pp. 58-67. U.S.C. 154(b) by 15 days. (Continued) (21) Appl. No.: 13/311,468 Primary Examiner Š Caridad Everhart (22) Filed: Dec. 5, 2011 (74) Attorney, Agent, or Firm Š Dominic M. Kotab Related U.S. Application Data (57) ABSTRACT (60) Provisional application No. 61/419,988, filed on Dec. In one embodiment, a tunable resistor/transistor includes a 6, 2010. porous material that is electrically coupled between a source electrode and a drain electrode, wherein the porous material (51) Int. Cl. acts as an active channel, an electrolyte solution Saturating the HOIL 2L/00 (2006.01) active channel, the electrolyte solution being adapted for (52) U.S. Cl. altering an electrical resistance of the active channel based on USPC 438/82:438/49; 257/E21.005 an applied electrochemical potential, wherein the active (58) Field of Classification Search channel comprises nanoporous carbon arranged in a three USPC .. 204/450; 438/82, 49; 257/E21.04, dimensional structure. In another embodiment, a method for 257/E21005 forming the tunable resistor/transistor includes forming a See application file for complete search history. Source electrode, forming a drain electrode, and forming a monolithic nanoporous carbon material that acts as an active (56) References Cited channel and selectively couples the source electrode to the U.S. PATENT DOCUMENTS 4.385,274. A * 5/1983 Shimada et al. . 324f71.6 6,325,909 B1 12/2001 Lietal. 7,091,096 B2 8/2006 Balasubramanian et al. 7,205,699 B1 4/2007 Liu et al. 7,211,854 B2 5, 2007 Bertin et drain electrode electrically. In any embodiment, the electro lyte Solution saturating the nanoporous carbon active channel is adapted for altering an electrical resistance of the nanopo rous carbon active channel based on an applied electrochemi cal potential. 20 Claims, 7 Drawing Sheets

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US 8,703.523 B1 Page 2 (56) References Cited U.S. PATENT DOCUMENTS 7,709,880 B2 5, 2010 Bertin et al. 7,947,371 B2 5/2011 Boussaad et al. 7,973,074 B2 7, 2011 Demadrille et al. 2001/0023986 A1 20O2/O1271.71 A1 2005, OO63244 A1 2005, 0103706 A1 2006, 0021881 A1 2006, OO24871 A1 2006, O138896 A1 2006/0240238 A1 2008.0024902 A1 2008.OO79027 A1 4/2008 Bertin et al. 2009/0021106 A1 1/2009 Baughman et al. 2009,026.9667 A1* 10, 2009 Antonietti et al. 429,2314 2009/0272967 A1 11/2009 Afzali-Ardakani et al. 2009,0278556 A1 11, 2009 Man et al. 20090315631 A1 12, 2009 Ham et al. 2010.0084631 A1 4/2010 Boland et al. 2010. 0230298 A1 9, 2010 Biener et al. 2010/0261058 A1 10/2010 Lopatin et al. 2010/0261071 A1 10/2010 Lopatin et al. 2010/0268312 A1 10, 2010 Wallace et al. 9, 2001 Mancevski 9/2002 Smalley et al. 3/2005 Bertin et al. 5, 2005 Bennett et al. 2/2006 Soundarrajan et al. 2, 2006 Balasubramanian et al. 6, 2006 Makansi 10/2006 Boussaad et al. 1/2008 Slafer 2010/0310933 A1* 12/2010 Jiang et al. .. 429,188 2011/000208.6 A1 1/2011 Feaver et al. .. 361,502 2011/0068290 A1 3f2011 Haddon et al. 252/62.51 R. 2011/0163296 A1* 7, 2011 Pace et al. .. 257/24 2012/0026643 A1* 2, 2012 Yu et al. 361,5O2 2012/01 15295 A1* 5, 2012 Lin et al. .. 438,268 FOREIGN PATENT DOCUMENTS WO O2/O55769 A1 T 2002 WO 2005/034204 A2 4/2005 WO 2005/084378 A2 9, 2005 WO 2006,138263 A2 12/2006 WO 2007/103832 A2 9, 2007 WO 2007, 11414.0 A1 10, 2007 WO 2009,132894 A1 11, 2009 WO 2010/019942 A2 2, 2010 WO 2010/120813 A2 10/2010 WO 2010/120995 A1 10/2010 WO 2011/005.375 A2 1, 2011 OTHER PUBLICATIONS Rahman et al., fiEnhanced lithium storage in a VO(2)(B)-multiwall carbon nanotube microsheet composite prepared via an in situ hydrothermal process.fl 2010 Elsevier Ltd., Electrochimica Acta, vol. 56, pp. 693-699. 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Janes et al., fiElectrochemical characteristics of nanoporous carbide derived carbon materials in various nonaqueous electrolyte Solu tions.fl 2006 The Electrochemical Society, Inc., Journal of the Elec trochemical Society, vol. 153, No. 1, pp. A113-A116. Arulepp et al., fiThe advanced carbide-derived carbon based Supercapacitor.fl 2006 Elsevier B.V., Journal of Power Sources, vol. 162, pp. 1460-1466. Janes et al., Electrochemical characteristics of nanoporous carbide derived carbon materials in non-aqueous electrolyte solutions, 2004 Elsevier B.V., Electrochemistry Communications, vol. 6, pp. 313 3.18. Jin et al., fiSign-inverted Surface stress-charge response in nanoporous gold.fl 2008 Elsevier B.V., Surface Science, vol. 602, pp. 3588-3594. Jin et al., fiElectrochemical properties of carbon aerogels derived from resorcinol-formaldehyde-aniline for Supercapacitors.fl 2011 Emerald Group Publishing Limited, Pigment & Resin Technology, vol. 40, No. 3, pp. 175-180. Liet al., fiStructure and electrochemical properties of carbon aerogels Synthesized at ambient temperatures as Supercapacitors. 2007 Elsevier B.V., Journal of Non-Crystalline Solids, vol. 354, pp. 19-24. Liu et al., fiCarbon aerogel spheres prepared via alcohol Supercritical drying.fl 2006 Elsevier Ltd., Carbon, vol. 44, pp. 2430-2436. Lowy et al., fiNonobatteries: Decreasing Size Power Sources for Growing Technologies.fl 2008 Bentham Science Publishers Ltd., Recent Patents on Nanotechnology, vol. 2, pp. 208-219. Lust et al., fiInfluence of electrolyte characteristics on the electro chemical parameters of electrical double layer capacitors.fl 2004 Springer-Verlag, J. Solid State Eelctrochem, vol. 8, pp. 488-496. Mulik et al., fiMacroporous Electrically Conducting Carbon Net works by Pyrolysis of Isocyanate-Cross-Linked Resorcinol-Formal dehyde Aerogels.fl 2008 American Chemical Society, Chem. Mater, vol. 20, pp. 6985-6997. Palmre et al., fiElectroactive polymer actuators with carbon aerogel electrodes.fl 2011 The Royal Society of Chemistry, J. Mater. Chem. vol. 21, pp. 2577-2583. Permann et al., fiElectrical double layer characteristics of nanoporous carbon derived from titanium carbide.fl 2005 Elsevier Ltd., Electrochimica Acta, vol. 51, pp. 1274-1281. Bjornbom, Pehr, “Charge/discharge of an electrochemical Supercapacitor electrode pore; non-uniqueness of mathematical models.fl 2006 Elsevier B.V., Electrochemistry Communications, vol. 9, pp. 211-215. Branzoi et al., fiModified Electrodes Obtained by Electrochemical Codeposition of Some Conducting Polymers and Carbon Nanotubes,fl Journal: Revue Roumaine De Chimie 2011, vol. 56, No. 1, pp. 73-84.

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US 8,703.523 B1 Page 3 (56) References Cited OTHER PUBLICATIONS Brogioli et al., fiA prototype cell for extracting energy from a water Salinity difference by means of double layer expansion in nanoporous carbon electrodes.fl 2011 The Royal Society of Chemistry, Energy Environ. Sci., vol. 4, pp. 772-777. Sun et al., fiNew concept of in situ carbide-derived carbon/xerogel nanocomposite materials for electrochemical capacitor, 2011 Elsevier B.V., Materials Letters, vol. 65, pp. 1392-1395. Tonurist et al., fiInfluence of Mesoporous Separator Properties on the Parameters of Electrical Double-Layer Capacitor Single Cells.fl 2009 The Electrochemical Society, Journal of the Electrochemical Society, vol. 156, No. 4, pp. A334-A342. Torop et al., fiFlexible supercapacitor-like actuator with carbide derived carbon electrodes.fl 2011 Elsevier Ltd., Carbon, vol. 49, pp. 3113-3119. Fang et al., fiSurface modification of carbonaceous materials for EDLCs application.fl 2005 Elsevier Ltd., Electrochimica Acta, vol. 50, pp. 3616-3621. Fang et al., fiA novel carbon electrode material for highly improved EDLC performance.fl 2006 American Chemical Society, J. Phys. Chem. B., vol. 110, pp. 7877-7882. Fang et al., fiInfluence of hydrophobisation of carbon surface on electrochemical capacitor performance.fl 2007 Elsevier B.V., Journal of Electroanalytical Chemistry, vol. 609, pp. 99-104. Fischer et al., fiElectroless deposition of nanoscale MnO2 on ultraporous carbon nanoarchitectures: Correlation of evolving pore solid structure and electrochemical performance.fl 2008 The Electro chemical Society, Journal of the Electrochemical Society, vol. 155, No. 3, pp. A246-A252. Gajendran et al., fiPolyaniline-carbon nanotube composites.fl 2008 IUPAC, Pure Appl. Chem., vol. 80, No. 11, pp. 2377-2395. Han et al., fiNovel route to pure and composite fibers of polypyrrole.fl 2006 Wiley Periodicals, Inc., Journal of Applied Polymer Science, vol. 103, pp. 1490-1494. Hinds et al., fiAligned multiwalled carbon nanotube membranes.fl Jan. 2, 2004, Science, vol. 303, pp. 62-65. Honda et al., fiElectrochemical properties of Pt-modified nano-hon eycomb diamond electrodes.fl 2001 Elsevier Science B.V., Journal of Electroanalytical Chemistry, vol. 514, pp. 35-50. Hughes et al., fiThe effect of nanotube loading and dispersion on the three-dimensional nanostructure of carbon nanotube-conducting polymer composite films,fl 2003 Materials Research Society, Mat. Res. Soc. Symp. Proc., vol. 739, pp. 211-216. Itoh et al., fiFuel Cell-related Reaction Activities of Nanoporous Metallic Platinum.fl 2010 Adsorption Science & Technology, vol. 28. No. 1, pp.39-47. Janes et al., fiOrganic carbonate-organic ester-based non-aqueous electrolytes for electrical double layer capacitors.fl 2005 Elsevier B.V., Electrochemistry Communications, vol. 7, pp. 510-514. Janes et al., fiVoltammetric and electrochemical impedance spectros copy studies of the nanoporous carbon 1 M (C2H5)(3)CH3NBF4 electrolyte solution interface.fl 2004 Elsevier B.V., Journal of Electroanalytical Chemistry, vol. 569, pp. 257-269. Janes et al., fiInfluence of solvent nature on the electrochemical characteristics of nanoporous carbon/1 M (C2H5)(3) CH3NBF4 electrolyte solution interface.fl 2004 Elsevier B.V., Surface Science, vol. 560, pp. 145-157. Jang et al., fiElectrochemical capacitor performance of hydrous ruthenium oxide mesoporous carbon composite electrodes.fl 2003 Elsevier Science B.V., Journal of Power Sources, vol. 123, pp. 79-85. Jinet al., “Stable Support based on highly graphitic carbon Xerogel for proton exchange membranefuel cells.fl 2010 Elsevier B.V., Journal of Power Sources, vol. 195, pp. 6323-6328. Kim et al., fiElectrical, magnetic, and optical properties of pi-conju gated polymer nanotubes and nanowires.fl 2004 World Scientific Publishing Company, Journal of Nonlinear Optical Physics & Mate rials, vol. 13, Nos. 3 & 4, pp. 547-551. Kim et al., fiThe Role of Metallic Fe and Carbon Matrix in Fe(2)O(3)/ Fe/Carbon Nanocomposite for Lithium-Ion Batteries.fl 2010 The Electrochemical Society, Journal of the Electrochemical Society, vol. 157, vol. 4, pp. A412-A417. Li et al., fiPore characteristics and electrochemical performance of ordered mesoporous carbons for electric double-layer capacitors.fl 2006 Elsevier Ltd., Electrochimica Acta, vol. 51, pp. 5715-5720. Liu et al., fiCarbon Xerogels as Pt catalyst Supports for polymer electrolyte membrane fuel-cell applications.fl 2009 Elsevier B.V. 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U.S. Patent Apr. 22, 2014 Sheet 7 Of 7 US 8,703,523 B1 CO – O2 Fon a source electode w 74 For a rail electrode For a monoithic nanoporous carbon materia that acts as an active channel that selectively coupies f{}8 the sofce eectrode to the drai electrode eiectrically FG. 7 😯 Alter an electrica resistance of a nanopogous – 82 carbor active channe by aterig an applied electrochemical potential of an eectrolyte FG. 8

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US 8,703,523 B1 1. NANOPOROUS CARBON TUNABLE RESISTOR/TRANSISTOR AND METHODS OF PRODUCTION THEREOF RELATED APPLICATION This application claims priority to U.S. Provisional Patent Appl. No. 61/419,988, filed Dec. 6, 2010, which is herein incorporated by reference. The United States Government has rights in this invention pursuant to Contract No. DE-AC52-07NA27344 between the United States Department of Energy and Lawrence Liver more National Security, LLC for the operation of Lawrence Livermore National Laboratory. FIELD OF THE INVENTION The present invention relates to an electrochemically con trolled tunable resistor/transistor, and more particularly, to a nanoporous carbon tunable resistor/transistor. BACKGROUND It is known that the resistance of a thin metal film can be reversibly tuned via the application of an external charge in an electrolyte where the Helmholtz double layer is utilized as the gate electrode. In this context, the idea of an electrochemi cally gated all-metal device is related to the well known field-effect transistor (FET), where the electronic transport through a semiconductor channel is controlled by an external gate potential. However, the effect, i.e., the change in resistance (AR/R) is only about 1-2% in the case of a pure metal due to a very large intrinsic carrier density and very short Screening length resulting from the very large intrinsic carrier density. This restricts the selection of the pure metal to materials that are stable in an electrochemical environment, which are inert, noble metals and are extremely expensive and heavy. The size of the Surface charge induced variation during electronic transport in a metallic conducting material increases with an increase in Surface-to-volume ratio. However, most metallic materials with very high Surface-to-volume ratio. Such as de-alloyed metals, are not thermodynamically stable. Any Supply of external energy thus reduces the Surface area and the size of Surface related effects. Accordingly, a material which could be used in these electrochemical environments and remain stable and do not suffer from the deficiencies of inert, noble metals would be very beneficial. SUMMARY In one embodiment, a tunable transistor includes a porous material that is electrically coupled between a source elec trode and a drain electrode, wherein the porous material acts as an active channel, an electrolyte Solution saturating the active channel, the electrolyte solution being adapted for altering an electrical resistance of the active channel based on an applied electrochemical potential, wherein the active channel comprises nanoporous carbon arranged in a three dimensional structure. In another embodiment, a method for forming a tunable transistor includes forming a source electrode, forming a drain electrode, and forming a monolithic nanoporous carbon material that acts as an active channel and selectively couples the source electrode to the drain electrode electrically. According to another embodiment, a method for tuning a tunable resistor/transistor includes altering an electrical resis 10 15 25 30 35 40 45 50 55 60 65 2 tance of a nanoporous carbon active channel by altering an applied electrochemical potential of an electrolyte, wherein the electrolyte Saturates the nanoporous carbon active chan nel, and the nanoporous carbon active channel is selectively coupled to a source electrode and a drain electrode electri cally. In yet another embodiment, a tunable resistor/transistor includes a nanoporous carbon active channel electrically coupled between a source electrode and a drain electrode, the nanoporous carbon active channel having a monolithic three dimensional structure Such as a carbon aerogel, and an elec trolyte solution saturating the nanoporous carbonactive chan nel, the electrolyte solution being adapted for altering an electrical resistance of the nanoporous carbon active channel based on an applied electrochemical potential, wherein the carbon aerogel is doped with an element selected from nitro gen, oxygen, fluorine, and boron, the carbon aerogel has a surface area of greater than about 3000 m/g, the electrolyte Solution is an ionic liquid including at least one of 1-Ethyl 3-methylimidazolium tetiafluoroborate (EMIMBF), 1-Bu tyl-3-methylimidazolium hexafluorophosphate (BMIMPF), and trioctylmethylammonium bis(trifluoromethyl-sulfonyl) imide or an aqueous or nonaqueous electrolyte Solution including at least one of LiF, NaF. KF, KOH, KC1, HSO, HCIO, LiCIO, NaClO4. EtNPF, Et NBF, Bt. NPF, and Bt.NBF. Other aspects and embodiments of the present invention will become apparent from the following detailed descrip tion, which, when taken in conjunction with the drawings, illustrate by way of example the principles of the invention. BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 shows morphology characteristic of a carbon aero gel, according to one embodiment. FIG. 2 shows an experimental setup that includes a minia turized electrochemical cell, according to one embodiment. FIGS. 3A-3B show cyclovoltammograms obtained from activated carbon aerogels with different Surface areas, according to one embodiment. FIGS. 4A-4C show changes in resistance of a carbon aero gel working electrode while the electrochemical potential of the carbon aerogel working electrode is periodically changed in an aqueous electrolyte, according to various embodiments. FIGS. 5A and 5B show pulse current charging and dis charging of a carbon aerogel. Over time, and the correspond ing change in resistance, respectively. FIG. 6 shows a tunable resistor/transistor, according to one embodiment. FIG. 7 is a flow diagram of a method according to one embodiment. FIG. 8 is a flow diagram of a method according to one embodiment. DETAILED DESCRIPTION The following description is made for the purpose of illus trating the general principles of the present invention and is not meant to limit the inventive concepts claimed herein. Further, particular features described herein can be used in combination with other described features in each of the various possible combinations and permutations. Unless otherwise specifically defined herein, all terms are to be given their broadest possible interpretation including meanings implied from the specification as well as meanings understood by those skilled in the art and/or as defined in dictionaries, treatises, etc.

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