If you are looking for capacitance information from CV you need to either be using a surface mode acquisition or an analog ramp, and not all systems have one of those options. Default CV settings from a digital potentiostat will be digital staircase with the sampling done near the end of the step, and that will not collect most of the capacitive current.

Perhaps you could provide some more information. Is there anything else in your working electrode besides ZIF-8 and binder? What sort of mass of active material are you using?

If ZIF-8 is an insulating MOF (?) then enhancing the conductivity of your electrode might be necessary to get more capacitance.

Hi Jacob,

Thank you very much for your consideration and reply,

I am using a VMP3 VSP Bio Logic instrument, is it ok?

Hi Michael,

Thanks for reply

I am just using a mixture of ZIF-8 and Nafion(which is a conductive binder) and I believe that the mass of my MOF on the working electrode is 1.44mg, the problem is that I can not find any reported number for capacitance of pure ZIF-8 in the literature to compare my numbers with.my current numbers indicate that my specific capacitance is 340 mF/g and my areal capacitance is 0.63 mf/cm^2.

To provide you with more clarification ZIF-8 like other MOFs is not a good electrical conductor but I am going to improve its conductivity using some methods, but in order to just show that I have improved the capacitance, first I need to take some control tests with the pristine ZIF-8. but I do not know whether or not my numbers are reliable.(?)

I'm not sure if [your] system has an analog scan generator (it may be an option) but I don't think it can do the surface mode acquisition. You would have to contact them directly, but I suspect you are not capturing the capacitive current.

To Jacob,

Thanks.So you think that my numbers are small too?

Well, it seems low, but I don't know enough about the material to really say. I do know that, while CV can be very good for getting capacitance, if you don't have the correct setup, it won't work, and you're better off with EIS or galvanostatic charge/discharge.