4. For such a thick coating with high coating resistance, a potential perturbation of 20 mV should be employed during the EIS measurement. 5. In fact, for such a thick coating, polarization measurement is inappropriate. Moreover, it is unacceptable that the value of anode and cathode slopes were as high as several hundreds. This is completely wrong. The polarization data should be removed from the text. 6. Much more detailed experimental parameters should be given, such as the XRD and Raman characterization parameters. 7. Moreover, the authors should be illustrated that during the repeated test, whether different specimens were employed. This is mandatory.