Ko, Jesse S. Kim, Hyung-Seok 2024-01-19T21:03:49Z 2024-01-19T21:03:49Z 2021-09-05 2018-12-31 0169-4332 https://pubs.kist.re.kr/handle/201004/120559 Electrochemical energy storage (EES) systems rely on novel materials to meet stringent performance demands in terms of both high energy and high power. Although several new materials have been identified for EES, one method that seeks to amplify material properties has been to modulate morphologies at the nanoscale. This improvement in electrochemical properties is in large part due to the enhancement in surface area and mitigation of solid-state diffusion at the nanoscale domain. By using sodium titanate (Na2Ti3O7) as a model compound, we employ efficient synthetic routes to prepare titanate nanosheets and nanotubes, and assess their charge-storage properties in both Li- and Na-ion non-aqueous electrolytes. Moreover, nanocomposites comprising reduced graphene oxide are constructed to further enhance rate capability. We perform a fundamental electroanalytical treatment of the charge-storage properties for titanate nanosheets and nanotubes and identify the underlying rate-determining mechanisms by kinetic analysis. In both Li- and Na-ion electrolytes, the nanotube-reduced graphene oxide nanocomposite exhibits pseudocapacitive behavior, indicated by broad voltammetric features and sloping charge-discharge voltage profiles under galvanostatic mode. This corresponding charge-storage process supports high capacities of 170 and 80 mAh g(-1) in a Li- and Na-ion system, respectively, based on constant current measurements at a C-rate of 5C. English ELSEVIER SCIENCE BV ELECTROCHEMICAL ENERGY-STORAGE CARBON NANOTUBES NANOSTRUCTURED MATERIALS STRUCTURAL FEATURES MULTILAYER GRAPHENE BATTERY ANODE PERFORMANCE NANOSHEETS INTERCALATION EXFOLIATION Lithium- and sodium-ion storage properties of modulated titanate morphologies in reduced graphene oxide nanocomposites Article 10.1016/j.apsusc.2018.08.087 1 APPLIED SURFACE SCIENCE, v.462, pp.276 - 284 APPLIED SURFACE SCIENCE 462 276 284 scie scopus 000447741800033 2-s2.0-85051630630 Chemistry, Physical Materials Science, Coatings & Films Physics, Applied Physics, Condensed Matter Chemistry Materials Science Physics Article ELECTROCHEMICAL ENERGY-STORAGE CARBON NANOTUBES NANOSTRUCTURED MATERIALS STRUCTURAL FEATURES MULTILAYER GRAPHENE BATTERY ANODE PERFORMANCE NANOSHEETS INTERCALATION EXFOLIATION Electrochemical energy storage Battery Pseudocapacitor Anode Nanotube Nanosheet