阶梯形貌铁基普鲁士蓝制备及性能

Preparation and Performance of Stepped Surface Iron-based Prussian Blue

采用柠檬酸辅助单一源法水热制备了具有表面从边缘向中心依次凹陷降低形貌的铁基普鲁士蓝(SFePBA)。与典型立方形貌FePBA(C-FePBA)相比,BET测试证明阶梯型特殊形貌使其具有增大一倍的比表面积,EIS测试证明其具有更低的阻抗。不同扫描速率下的循环伏安分析证明其具有赝电容效应,从而具有优异的倍率性能。电流密度由0.1 A/g增大到5 A/g,容量几乎不变,保持率为94%。此外不同电压下的非原位XRD测试证明其具有良好的结构可逆性,循环稳定性优良,在0.6 A/g电流密度下循环1500次后容量保持率为89%。

Iron-based Prussian blue with a stepped morphology(S-FePBA)was prepared by citric acid-assisted single-source hydrothermal method in this paper.Compared with the typical cubic morphology FePBA(C-FePBA),it shows larger specific surface area due to its unique stepped morphology according to the BET test.And the EIS test shows that it has a lower impedance.Cyclic voltammetry analysis at varied scan rates proves that it has a pseudocapacitance effect,which contribute to its good rate performance.When the current density increases from 0.1 A/g to 5 A/g,it shows no obvious capacity fading with 94%capacity retention.In addition,the ex-situ XRD test at different voltages shows that it has good structural reversibility,leading to an excellent cycling stability with capacity retention of 89%over 1500 cycles at 0.6 A/g.