Dear Rajkiran Shivade , you can find details for making ink and coating on electrode in the supplementary information of any articles on ORR/OER.

You can read the SI part of the following articles

Article Scalable Molten Salt Synthesis of Platinum Alloys Planted in...

Hi you can proceed drop casting on your electrode surface.

Firstly it is necessary to disperse your electrocatalyst in adequate solvent for example water, then you can add nafion as linker and ionic membrane, after that you can drop the ink on your electrode surface and keep dry.

By the way you can modify your electrode surface by electropolymerization if your product is electropolymerizable. You can also do that by electrodiposition.

There is several ways to do that.

Dear Rajkiran Shivade,

you should choose a catalytic ink preparation protocol to meet your standars (some techniques use ethanol or methanol or water and amount of alcochol, others use different amounts of nafion, etc. you should choose wise and always have in mind the metals/materials that compose your catalyst- their solubility, etc.).

Then, you should mix everythink well in ultrasonicator or magnetic stirrer (the instrument used, depends on the preparation protocol) and then you should deposite the appropriate amount of ink onto the rotating disk electrode (later you can use this amount to theoritically calculate the metal loading onto the electrode).

Then, the drying process will follow1) in room temperature, 2) or under thermal raridation, 3) or by using the rotating disk electrode with very small velocity (that ensures uniform drying of the paste onto the electrode surface).

***you can search for papers concerning ORR and OER experiments in three-electrode system, in the experimental procedure chapter the catalytic ink preparation should be mentioned.

how can we calculate theoreticallythe loading of electrocatalyst on the electrode?

is it necessary to dry electrocatalys deposited on the electrocatalyst using oven?

is it possible to put the substrate GC in case of rotating disk electrode in the autolcalve along with the solution and then automatically at the end of reaction the electrocatalyst is deposited on to the GC on rotating disk electrode?

P.S : I have read my papers where Ni FOAM is put in the autocalve for three electrod system