Nano-composite LiMnPO4 as new insertion electrode for electrochemical supercapacitors
| Autor: | R. Anslin Star, Ajit R. Kulkarni, S.R.S. Prabaharan, M.S. Michael |
|---|---|
| Jazyk: | angličtina |
| Rok vydání: | 2015 |
| Předmět: |
Cathode Material
Li-Ion Capacitors Working electrode Materials science Rechargeable Lithium Batteries Performance Meso-Porous Carbon General Physics and Astronomy chemistry.chemical_element Storage Nanotechnology Electrolyte Aqueous-Electrolyte Electrochemistry Reference electrode Mn Supercapacitors General Materials Science Supercapacitor Aqueous solution Limnpo4 Electrochemical Ex-Situ Carbon Coating Fe Lixmpo4 M Carbon Chemical engineering chemistry Electrode |
| Zdroj: | IndraStra Global. |
| ISSN: | 2381-3652 |
| Popis: | Nano-composite olivine LiMnPO4 (nC-LMP) was found to exhibit facile pseudo-capacitive characteristics in aqueous as well as non-aqueous electrolytes. We demonstrated employing nC-LMP as positive electrode in hybrid electrochemical capacitors namely Li-Ion hybrid capacitors (LIC). Adapting a simple CVD technique, nano-crystallites of LiMnPO4 were coated with carbon monolayers of similar to 2 nm thick to circumvent its poor intrinsic electronic conductivity. The novelty is that the single crystallites were intimately covered with carbon ring and networked to the neighboring crystallites via the continuous carbon wire-like connectivity as revealed from HRTEM analysis. Single electrode faradic capacitance of 3025 Fg(-1) (versus standard calomel reference electrode) was deduced for carbon coated LMP, the highest reported hitherto in Li+ aqueous electrolytes. Employing nC-LMP as working electrode versus an activated carbon (AC), we obtained a high specific energy of 28.8 Wh kg(-1) with appreciable stability in aqueous electrolytes whereas in nonaqueous electrolyte there is an obvious increase in energy density (35 Wh kg(-1)) due to wider potential window. That is, a full cell version of LIC, AC vertical bar Li+vertical bar LMP, was fabricated and demonstrated its facile cycling characteristics via removal/insertion of Li+ within nC-LMP (positive electrode) and the electrosorption of Li+ into mesoporous carbon (AC) (negative electrode). Such cells ensured a typical battery-like charging and EDLC-like discharging characteristics of LIC type electrochemical capacitors (ECs) which are desired to enhance safety and energy densities. (C) 2015 Elsevier B.V. All rights reserved. |
| Databáze: | OpenAIRE |
| Externí odkaz: |
|