Electrochemical properties of Na MnFe(CN)6·zH2O synthesized in a Taylor-Couette reactor as a Na-ion battery cathode material

Taylor-Couette reactors allow short reaction times and enable the synthesis of powders with uniform particle size, and thus are suitable for preparing secondary battery cathode materials . Herein, cubic, monoclinic , and rhombohedral Na x MnFe(CN) 6 · z H 2 O samples were prepared in a Taylor-Couette reactor at various drying conditions/temperature and were shown to exhibit structure-dependent electrochemical properties . When cycled at 0.1 C in a potential range of 2.0–4.0 V, cubic-, monoclinic-, and rhombohedral-structured samples exhibited reversible discharge capacities of 89.5, 91.4, and 150.1 mAhh g −1 , respectively. Importantly, the rhombohedral-structured sample not only showed the highest reversible discharge capacity but also exhibited excellent capacity retention (88.03%) after 50 cycles at 0.5 C (300 mA g −1 ), which was ascribed to its extremely low interstitial water content.