Due to its abundance and ecological friendliness, alpha-manganese dioxide (α-MnO₂) is recognized as a cost-effective bifunctional electrocatalyst for oxygen reduction reaction (ORR) and oxygen evolution reaction (OER). The α-MnO₂ is widely used in rechargeable zinc-air batteries (ZABs). However, its performance gradually deteriorates upon charge-discharge cycling. Thus, its deactivation mechanisms must be understood to tackle such an issue. Herein, the deactivation mechanisms of MnO₂ are duly investigated via the density functional theory–based analysis, where the MnO₂ electrocatalysts are modeled based on the X-ray diffraction (XRD) profiles of the fresh MnO₂ dominated by the α-MnO₂ (211) and the spent one dominated by the β-MnO₂ (110). Based on the simulated event of ORR, the *OOH species exhibited the strongest chemisorption to all of the surfaces, followed in order by *O and *OH, respectively. Regarding the surface distortion due to the species presented during ORR, it was investigated by the Bader charge and charge density difference analysis. It was found that all surface experienced some degrees of distortion confirmed by the calculated strain value, where the most distorted surface is the deactivated MnO₂, the β-MnO₂ (110). As the MnO₂ phase transformation from α to β during ORR generates a less active surface, the low activity found on β-MnO₂ (110) confirmed by the ORR overpotential (η) derived from its Gibbs free energy diagram is due to the limiting elementary step converting *OOH to *O, which blocks the propagation towards the final product. While the OER performance for the fresh and spent catalysts are similar. Hence, the deactivation of the MnO₂ electrocatalyst occurring during ORR is due to (1) the phase change from α-MnO₂ to β-MnO₂ and (2) the limiting reaction, which leads to the formation of *OOH species rather than the H₂O product. As a design guideline, the prevention of phase transformation is one of the key factors towards high-performance MnO₂-based ORR/OER electrocatalysts.

由于其丰度和生态友好性，α-二氧化锰（α-MnO的₂）是公认的用于氧还原反应（ORR）和析氧反应（OER）具有成本效益的双功能电催化剂。α-MnO的₂被广泛用于可再充电的锌-空气电池（ZABs）。但是，其性能随着充放电循环而逐渐劣化。因此，必须了解其停用机制以解决此类问题。在此，的MnO的停用机制₂通过密度泛函理论为基础的分析，其中所述的MnO都得到适当调查₂电催化剂是基于X射线衍射（XRD）的新鲜的MnO轮廓建模₂由主导α-MnO的₂（211）和用过的一个由β-MnO的主导₂（110）。基于ORR的模拟事件，* OOH物种对所有表面均表现出最强的化学吸附性，依次依次为* O和* OH。关于在ORR期间出现的物质引起的表面变形，通过Bader电荷和电荷密度差分析对其进行了研究。结果发现，所有表面经历了一些失真度由计算出的应变值，其中最扭曲表面是失活的MnO证实₂，β型的MnO ₂（110）。由于MnO的₂从α相转变成β期间ORR产生活性较低的表面，所述低活性上β-MnO的发现₂（110）由其吉布斯自由能图得出的ORR过电势（η）证实是由于将* OOH转换为* O的有限基本步长，从而阻止了向最终产物的传播。虽然新鲜和用过的催化剂的OER性能相似。因此，MnO的失活₂ ORR期间发生的电是由于（1）的相位从α-MnO的变化₂至β-MnO的₂和（2）的限制性反应，这导致* OOH物质的形成，而不是H ₂ O产物。作为设计指南，防止相变是制备高性能MnO ₂基ORR / OER电催化剂的关键因素之一。