What is your cell (and the RE) ?

dear Ioannis Samaras ,

i am using activated carbon as WE, Ag/AgCl as RE, and platinum sheet as CE, the electrolyte is 1M of KOH.

if i set the time for charge and discharge i can get the charge-discharge curve easily, but when i set it to be controlled by potential this what happens, here the charge curve never reach the set potential cut-off , i dont know why?

How do you preset[1] the (low-high) potentials[2] driven mode ?

1. Find the (low-high) potentials' limits (in this[2] GCD mode) from a (previous, diagnostic) CVL (set).

2. Quot. Oussama Khiter : "... but when i set it to be controlled by potential this what happens, here the charge curve never reach the set potential cut-off , i dont know why?."

dear Ioannis Samaras

sorry what it CVL?

since i am using Activated carbon i use the same potential window from 0 to 1 for CV and GCD as in literature , Could you please tell me how to determine the potential i should set for measurements from LSV?

Dear Oussama Khiter ,

in order to help you finding the (low-high) potentials, can you, please,

a) perform a CV (set[1]) from -1.1V up to 0.9V (WE vs Ag/AgCl),

and

b) show us your results (iv-plots) ?

1. CV rates (1, 10, 100) mV/s.

Dear Ioannis Samaras

here are the CV curves, if you can refer to a resource to determine the (low-high) voltage will be great.

Dear Oussama Khiter,

the ('activated') carbon is not, actually, working as expected, e.g. a SC (WE), and this partially-collateral quasi-Ohmic (parallel) current is, mainly (>>80%), due to the substrate (current collector).

So, you might like to retry/reconsider all about your (insufficient) activation process(es) of this carbon.

dear Ioannis Samaras ,

thank you, below the same sample with a different potential window(0-0,6 V), i performed CV and it showed somehow an EDLC shape, also i measured the ohmic resistance of the graphite sheet and found it 2 ohm. do you suggest any interpretation for this?

Dear Oussama Khiter,

can you:

1) redo the same CV with a different potential window(-0,6:0,3 V) ?

Also,

2) can you measure some EIS ?

Oussama Khiter,

Did you enter two times T1 and T2 when entering the information and before running GCD? The first time is related to the charging time and the second time is related to the discharging time, so most likely you left the second time to zero.

thank you Roghayyeh Hadizadeh ,

when i set T1 and T2 i got the correct graph of GCD, however in this case i sent the GCD to be controlled by potential not by time which means the electrodes takes their time to charge and discharge, i don't know if this is in every potentiosta but i am talking about CH instrument specifically.

thank you sir Ioannis Samaras ,

unfortunately the device is under maintenance and i will perform the suggested measurement soon.