Hello, I am researching the electrodeposition of Co and Cu multilayers on gold-plated silicon wafers. During the deposition I observed that the current reading was positive instead of negative. I understand electrodeposition is a reduction reaction and should correspond with a negative current. Can anyone help with more info on this and figure out what i am probably doing wrong. Thank you!
Chaitanya Kumar
I am using a three-electrode setup. The gold plated wafer is my working electrode (cathode), platinum mesh is my counter electrode (anode), and Ag/AgCl is a reference electrode. I am also using the Ch Instrument 760D series as a potentiostat, and I have confirmed the electrode connections severally with the manual. However i haven't been able to figure out why i am reading a positive current.
Some potentiostats display negative current as positive. Try to measure the real potential difference/current using a digital voltmeter.
Chaitanya Kumar
Thanks for the information, I was usually using -0.5V for Cu deposition and -1.0V for Co deposition; however I could see deposition. Anyway, I have managed to rectify the issue now.
Thank you once again.
Andrzej Lasia
Thanks for the insight. I ended up rectifying the issue. So I started by testing the electrodes of the potentiostat to confirm that i was injecting -0.5V for Cu and -1.0V for Co depositions. Apparently, there was a setting in the software that had set the Current polarity to " Cathodic Positive." So this setting was making all my current values Positive even though they were negative. So i just changed the current polarity to " Anodic Positive" and this rectified the issue and started displaying the expected negative current.
Basically reduced state (species) of the material is considered as deposited material, so please identify your reduced species and corresponding current, and use as deposition current.