title: One-step hydrothermal synthesis of mesoporous anatase TiO₂ microsphere and interfacial control for enhanced lithium storage performance.
abstract: Mesoporous TiO(2) anatase microspheres consisting of self-assembled nanocrystals have been synthesized by a one-step hydrothermal method at 120 (o)C using titanium-peroxo complex, without a post-calcination process. Transmission and scanning electron microscopic imaging reveal that diamond-shaped nanocrystals as primary particles, which are 20 nm in average width and 50 nm in length and oriented with (101) plane of anatase phase, are aggregated to form a secondary microsphere particle with 0.5-1 μm in diameter. BET analysis data show that the TiO(2) anatase particles possess significantly large surface area of 254 m(2) g(-1) with the pore size of ∼14 nm. Mesoporous TiO(2) anatase anode shows an enhanced lithium storage performance in pyrrolidinium-based ionic liquid electrolyte diluted with ethyl methyl carbonate, delivering 195 - 150 mAhg(-1) at the C/2 rate with 77 % capacity retention and 98-99 % Coulombic efficiencies over 50 cycles despite the absence of surface carbon-coating. AC impedance analysis results reveal that the formation of a stable solid electrolyte interphase (SEI) layer in diluted ionic liquid electrolyte induces the enhanced cycling performance. Control of electrode-electrolyte interfacial compatibility enables the enhancement of cycling performance and the preservation of microstructure. The data contribute to provide cost-efficient synthetic method for the TiO(2) and the interfacial control aspect of performance control for safer batteries.
authors.affiliation: Department of Fine Chemical Engineering & Applied Chemistry, Chungnam National University, Daejeon 305-764, South Korea.
authors.forename: Kyung-Ho
authors.initials: KH
authors.lastname: Lee
authors.forename: Seung-Wan
authors.initials: SW
authors.lastname: Song
mesh_terms: D011211:Electric Power Supplies; D004573:Electrolytes / Q000737:chemistry; D052578:Ionic Liquids / Q000737:chemistry; D008094:Lithium / Q000737:chemistry*; D053768:Metal Nanoparticles / Q000737:chemistry; D008863:Microspheres; D010316:Particle Size; D016062:Porosity; D013696:Temperature; D014025:Titanium / Q000737:chemistry*
chemical_list: D004573:Electrolytes; D052578:Ionic Liquids; C009495:titanium dioxide; D008094:Lithium; D014025:Titanium