Rational Design of Prussian Blue Analogues for Ultralong and Wide-Temperature-Range Sodium-Ion Batteries
Zhongxin Jing, Lingtong Kong, Muhammad Mamoor, Lu Wang, Bo Zhang, Bin Wang, Yanjun Zhai, Fengbo Wang, Guangmeng Qu, Yueyue Kong, Dedong Wang, Liqiang Xu
Abstract
Architecting Prussian blue analogue (PBA) cathodes with optimized synergistic bimetallic reaction centers is a paradigmatic strategy for devising high-energy sodium-ion batteries (SIBs); however, these cathodes usually suffer from fast capacity fading and sluggish reaction kinetics. To alleviate the above problems, herein, a series of early transition metal (ETM)–late transition metal (LTM)-based PBA (Fe-VO, Fe-TiO, Fe-ZrO, Co-VO, and Fe-Co-VO) cathode materials have been conveniently fabricated via an “acid-assisted synthesis” strategy. As a paradigm, the FeVO-PBA (FV) delivers a superb rate capability (148.9 and 56.1 mAh/g under 0.5 and 100 C, respectively), remarkable cycling stability over 30,000 cycles, high energy density (259.7 Wh/kg for the full cell), and a wide operation-temperature range (−60–80 °C). In situ / ex situ techniques and density functional theory calculations reveal the quasi-zero-strain and multielectron redox mechanisms of the FeVO-PBA cathode during cycling, supporting its higher specific capacity and stable cycling. It is considered that the d–d electron compensation effect between Fe and V enhanced the reversibility and kinetics of redox reactions and simultaneously improved the electronic conductivity and structural stability of the FeVO-PBA cathode. This work may pave a new way for the rational design of high-performance cathode materials with bimetallic reaction centers for SIBs.