| 초록 |
Co-precipitation processes affect the structural properties of Prussian Blue analogues (PBAs), such as the size, crystallinity, and the amount of interstitial water molecules, which are directly related to the electrochemical properties. Here, we unveil the dependence of electrochemical performance on the crystal properties of copper hexacyanoferrates (CuHCFe). As a result, the synthesized CuHCFe nanoparticles represent a polydisperse size distribution at low and high synthetic temperatures (Ts), benefitting from the nucleation rates. Taking advantage of fewer interstitial water molecules at high Ts, CuHCFe possesses high specific capacities at various current densities from 12 mA g-1 to 1200 mA g-1 rather than that synthesized at low Ts due to its small amount of interstitial water molecules. In addition, cyclic retention of CuHCFe with higher crystallinity synthesized at high Ts was improved (71.2% of initial capacity after 2500 cycles) than that of the counterpart CuHCFe at low Ts (63.0% of initial capacity after 2500 cycles). Our results suggest that high Ts effectively decreases the amount of interstitial water molecules occupying the site where Na-ions are inserted, inducing better electrochemical properties of CuHCFe. |
