Nano-Carbon battery Graphene synthesis Top-down CNT synthesis CVD reactor hydrocarbon gas Catalyst CNTs Chemical Modification COO O NO 2 COO COO COO Bottom-up O O NO NO 2 2 COO COO Nano-Carbons 20 nm Light-emitting Mesoporus carbon-silica Bright white light PL! Energy Storage - + Batteries Na+ Low cost Mg 2+ igh energy density Capacitors igh capacity Mg 2+ 2 Energy Solar 2 generation hn cv CuO 2 2 O Rechargeable Fuel Cell O 2 O-
Synthesis of Nanocarbons Carbon Nanotubes Graphene Chemical Vapor Deposition (CVD) [After CVD] Top-down approach C 4 C 2 4 C 3 O Carbon Source Catalysts Electric Furnace Graphite Graphene SWCNTs Graphene Bottom-up approach T. Inoue, S. Kawasaki, et al. Jpn. J. Appl. Phys. 50, 01AF07 (2011). Thermal CVD Plasma CVD Y. Ishii, S. Kawasaki, et al. Nanoscale 4, 6553 (2012). T. ayakawa, S. Kawasaki, et al. RSC Adv. 6, 22069 (2016). Mesoporous Carbons Ceramics Polymer Ceramics Carbon In addition to the simple carbon nanotubes, N-doped carbon nanotubes can also be prepared. Micelle Polymerization Micelle eat (N 2 flow) Mesopore Y. Ishii, S. Kawasaki, et al. Mater. Express 2, 23 (2012). Y. Ishii, S. Kawasaki, et al. Jpn. J. Appl. Phys. 50, 01AF06 (2011). Y. Ishii, S. Kawasaki, et al. J. Phys. Chem. C 117, 18120 (2013).
Modification of Carbon Nanotubes Encapsulation Edge Structure C 60 Quinones PAs Evaporation Method Open-SWCNTs Sulfur Phosphorous Poly-iodine Vacuumed grass-tube eat-treatment Closed-end Open-end A. Al-zubaidi, S. Kawasaki, et al. Phys. Chem. Chem. Phys. 14, 16055 (2012). Atomic Substitution N N N PhQ Washed with acetone (elimination of excess quinones) Electrochemical Method SWCNT WE RE CE < 1min Activated carbon fiber Filtration PhQ@SWCNTs I@SWCNTs N-doped SWCNT Pyridinic-N Pyrrolic-N Graphitic-N Z. Jang, S. Kawasaki, et al. Mater. Express 4, 331 (2014). Z. Jang, S. Kawasaki, et al. Mater. Express 4, 337 (2014). Surface Functionalization OC OOC O NO2 O. Song, S. Kawasaki, et al. Phys. Chem. Chem. Phys. 15, 5767 (2013). I. Mukhopadhyay, S. Kawasaki, et al. J. Nanosci. Nanotech. 10, 4089 (2010).
Energy Storage Devices Electric double layer capacitor (EDLC) Low capacitance Li-ion battery (LIB) Unsafe igh cost Low capacity Low temperate operation is hard
SWCNT Encapsulation Systems Functional Molecules Nanotube + S quinones P Energy storage I
Activities in Kawasaki s Lab. LIB Next generationlib Post LIB igh capacity anode Organic molecules @SWCNT Graphenes P@SWCNT Improve low temperature property Li-organic cells OM@SWCNT all solid batteries iodine@swcnt Metal-air cells etero-atom doped SWCNTs Dual-SWCNT cells Thin metal SWCNTs Li-S batteries sulfur@swcnts Na-ion batteries P@SWCNT Multi Valent ion batteries PhQ@SWCNT
Inorganic molecules @ SWCNTs P@SWCNTs STEM-EDX map igh resolution TEM Phosphorous atoms encapsulated in SWCNTs P@SWCNTs
Voltage / V ( vs. Li 1.5 Voltage / V ( vs. Li Inorganic 1.5 molecules @ 1.5 SWCNTs 1.5 0.5 0.5 Sodium-ion Battery Bulk P + Carbon Black (Simple Mixture) SWCNTs 0 0 1000 1000 2000 2000 Capacity / Capacity mah g 1 / mah g 1 Voltage / V ( vs. Li 0.5 Voltage / V ( vs. Li Phosphorous 0.5 Electrolyte: 0.5 M NaClO 4 / EC + DEC (1 : 1 v) Note) Measured without binder and conductive additives. 0 0 1000 1000 2000 2000 Capacity / Capacity mah g 1 / mah g 1 P @ SWCNTs (Encapsulation System) 3.0 3.0 C C 3.0 3.0 D D Voltage / V ( vs. Na / Na + ) 2.5 1.5 0.5 Voltage / V ( vs. Na / Na + ) 2.5 1.5 0.5 Reversible capacity is very low Voltage / V ( vs. Na / Na + ) 2.5 1.5 0.5 Voltage / V ( vs. Na / Na + ) 2.5 1.5 0.5 0 0 1000 1000 2000 2000 Capacity / Capacity mah g 1 / mah g 1 0 0 1000 1000 2000 2000 Capacity / Capacity mah g 1 / mah g 1 Y. Ishii, S. Kawasaki, et al. AIP Adv. 6, 035112 (2016). P@SWCNTs electrodes store Na-ion reversibly. (igh reversible capacity)
Organic molecules @ SWCNTs Lithium-ion Battery SWCNTs PhQ Electrolyte: M LiClO 4 / EC + DEC (1 : 1 v) Note) Measured without binder and conductive additives. PhQ + Carbon Black (Simple Mixture) PhQ + SWCNTs (Simple Mixture) PhQ @ SWCNTs (Encapsulation System) Y. Ishii, S. Kawasaki, et al. Phys. Chem. Chem. Phys. 18, 10411 (2016). Cycle performance was dramatically improved by the encapsulation!
Iodine molecules @ SWCNTs Redox Capacitor Conventional EDLC Y. Taniguchi, S. Kawasaki, et al. J. Nanosci. Nanotech. in press. [doi: 10.1166/jnn.2016.13006] Redox capacitor using electrochemical iodine encapsulation reaction of SWCNTs I@SWCNTs Energy density was dramatically increased! (20.7 F/g, 2.4 Wh/kg ---> 67.2 F/g, 7.8 Wh/kg)