论文标题
ZnMN2O4的电化学稳定性：了解Zn-Ion可充电电池容量和降解
Electrochemical stability of ZnMn2O4: Understanding Zn-ion rechargeable battery capacity and degradation
论文作者
论文摘要
我们提出了一个精致的Mn-Zn-H $ _2 $ o Pourbaix图，重点是与Zn/Mno $ _2 $可充电单元相关的参数。它绘制了MNO $ _2 $，Znmn $ _2 $ o $ $ _4 $，Znmn $ _3 $ o $ $ _7 $和mnooh的电化学稳定性边界。该图有助于对在充电/放电期间发生的过程和相位进行的实验观察（包括电荷/放电氧化还原峰的位置以及在可充电水电池中观察到的容量褪色的位置），以进行固定存储。提出的Pourbaix图通过观察到分别在放电和电荷过程中分别观察到电解锰二氧化碳对hetaerolite和chalcophanite的pH依赖性转化来验证。我们的结果可以指导现有水性Zn/MNO $ _2 $可充电细胞的操作条件（潜在范围和pH）的选择，以最大限度地延长其寿命。此外，电化学稳定性边界与操作条件之间的关系可以用作探索未来可充电电池的未来阴极材料的额外设计标准。
We present a refined Mn-Zn-H$_2$O Pourbaix diagram with the emphasis on parameters relevant for the Zn/MnO$_2$ rechargeable cells. It maps out boundaries of electrochemical stability for MnO$_2$, ZnMn$_2$O$_4$, ZnMn$_3$O$_7$, and MnOOH. The diagram helps to rationalize experimental observation on processes and phases occurring during charge/discharge, including the position of charge/discharge redox peaks and capacity fade observed in rechargeable aqueous Zn-ion batteries for stationary storage. The proposed Pourbaix diagram is validated by observing the pH-dependent transformation of electrolytic manganese dioxide to hetaerolite and chalcophanite during discharge and charge, respectively. Our results can guide the selection of operating conditions (the potential range and pH) for existing aqueous Zn/MnO$_2$ rechargeable cells to maximise their longevity. In addition, the relation between electrochemical stability boundaries and operating conditions can be used as an additional design criterion in exploration of future cathode materials for aqueous rechargeable batteries.
