Nanocrystal‐Assembled Porous Na3MgTi(PO4)3 Aggregates as Highly Stable Anode for Aqueous Sodium‐Ion Batteries. Issue 52 (29th August 2017)

• Record Type: Journal Article
• Authors: Zhang, Fang; Li, Wanfeng; Xiang, Xingde; Sun, Molong
• Is Part Of: Chemistry. Volume 23:Issue 52(2017)
• Page Start: 12944
• Page End: 12948
• Publication Date: 2017-08-29
• Subjects: anode material -- aqueous batteries -- electrochemical properties -- porous nanostructure; Chemistry -- Periodicals; 540
• DOI: 10.1002/chem.201703044
• Languages: English
• ISSNs: 0947-6539

Abstract

Abstract: Aqueous sodium‐ion batteries (SIBs) represent a class of green electrochemical technology for large‐scale storage of sustainable energies such as wind power and solar radiation, owing to their low cost, environmental friendliness, and reliable safety. However, there is still lack of available anode materials for aqueous SIBs. Herein, nanocrystal‐assembled porous Na3 MgTi(PO4 )3 aggregates are reported as novel anode material for aqueous SIBs. The crystal structure, morphological features, and electrochemical properties have been analyzed with X‐ray diffraction, scanning electron microscopy, transition electron microscopy, cyclic voltammetry, and charge/discharge measurements. As revealed, the material possesses a porous nanostructure composed of 5 nm nanocrystals and mesoporous channels. During Na‐insertion/extraction, it undergoes a one‐step single‐phase reaction mechanism through reversible electrochemistry of the Ti 4+ /Ti 3+ redox couple, showing a rechargeable capacity of 54 mAh g −1 and an average working potential of −0.63 V (vs. Ag/AgCl) at 0.2 C. More importantly, good rate capacity (33 mAh g −1 at 4 C) and excellent cycling performance (94.2 % capacity retention after 100 cycles at 0.5 C) are achieved due to the unique porous nanostructure and robust compositional framework. The finding in this work would create new opportunities for design of low‐cost, long‐cycling aqueous SIBs. Abstract : Titanic power : Aqueous sodium‐ion batteries (SIBs) represent a class of green electrochemical technology for large‐scale storage of sustainable energies such as wind power and solar radiation. Nanocrystal‐assembled porous Na3 MgTi(PO4 )3 aggregates can serve as novel anode material for aqueous SIBs, showing a reversible capacity of 54 mAh g −1, a reasonable working potential of −0.63 V (vs. Ag/AgCl) and a high capacity retention of 94.2 % after 100 cycles (0.5 C).