Lim, Soo Yeon Lee, Ji Hoon Kim, Sangryun Shin, Jaeho Choi, Wonchang Chung, Kyung Yoon Jung, Dae Soo Choi, Jang Wook 2024-01-20T01:33:35Z 2024-01-20T01:33:35Z 2021-09-01 2017-05 2380-8195 https://pubs.kist.re.kr/handle/201004/122819 We report amorphous iron phosphate with lattice water, namely FePO4. xH(2)O (x similar to 2.39), as a promising sodium-ion battery (SIB) cathode. After carbon coating, micrometer-sized FePO4.xH(2)O exhibits a reversible capacity that is higher than that of its counterpart without lattice water (130.0 vs 50.6 mAhg(-1) at 0.15C rate) along with clearly enhanced rate capability and cyclability. The superior electro-chemical performance of FePO(4.)xH(2)O is attributed to the lattice water that facilitates sodium-ion diffusion via enlarged channel dimensions and the screening of the electrostatic interactions between sodium ions and host anions. The amorphous phase is also advantageous in accommodating the stress created in the host framework during sodium-ion (de)intercalation. The presence of lattice water also protects the oxidation state of Fe from reductive surface carbon coating and slightly lowers the operation voltage via reduced inductive effect. The current study provides a useful insight into how to design SIB electrode materials particularly focusing on facile sodium-ion diffusion. English AMER CHEMICAL SOC CATHODE MATERIAL ELECTROCHEMICAL PROPERTIES RECHARGEABLE BATTERIES POSITIVE-ELECTRODE LITHIUM-INSERTION LAYERED CATHODE CRYSTAL WATER HIGH-ENERGY FEPO4 MAGNESIUM Lattice Water for the Enhanced Performance of Amorphous Iron Phosphate in Sodium-Ion Batteries Article 10.1021/acsenergylett.7b00120 1 ACS ENERGY LETTERS, v.2, no.5, pp.998 - 1004 ACS ENERGY LETTERS 2 5 998 1004 scie scopus 000401500200008 2-s2.0-85033672664 Chemistry, Physical Electrochemistry Energy & Fuels Nanoscience & Nanotechnology Materials Science, Multidisciplinary Chemistry Electrochemistry Energy & Fuels Science & Technology - Other Topics Materials Science Article CATHODE MATERIAL ELECTROCHEMICAL PROPERTIES RECHARGEABLE BATTERIES POSITIVE-ELECTRODE LITHIUM-INSERTION LAYERED CATHODE CRYSTAL WATER HIGH-ENERGY FEPO4 MAGNESIUM