That is a hard one ! One problem up front is that it is not possible to obtain "standard" conditions for such measurements i.e. preparing a 1 molar solution of dissolved graphite is a bit impossible (without making graphene oxide). The next issue is to write the (and only one) equilibrium equation related to the electrode potential.
For some of the oxidation reactions of graphite it is possible to obtain approximate standard potentials but these are normally around the water oxidation potential or higher (depending on pH and solvent) and not near the open circuit potential you would normally measure on at graphite electrode. The complication is that the water-graphite interaction is very limited (weak) compared to other possible equilibrium reactions e.g. from impurities.
For the temperature dependence of redox potentials; the Nernst equation is a reasonable guideline...
That is a hard one ! One problem up front is that it is not possible to obtain "standard" conditions for such measurements i.e. preparing a 1 molar solution of dissolved graphite is a bit impossible (without making graphene oxide). The next issue is to write the (and only one) equilibrium equation related to the electrode potential.
For some of the oxidation reactions of graphite it is possible to obtain approximate standard potentials but these are normally around the water oxidation potential or higher (depending on pH and solvent) and not near the open circuit potential you would normally measure on at graphite electrode. The complication is that the water-graphite interaction is very limited (weak) compared to other possible equilibrium reactions e.g. from impurities.
For the temperature dependence of redox potentials; the Nernst equation is a reasonable guideline...
Also based on our hands-on experience, the commercially available graphite tends to contain trace amounts of metals, which makes it unstable in most electrolytes. in other words, the open circuit potential of graphite electrode will fluctuate not only with temperature but also with time and solution chemistry.
What if you measure the Nomial Voltage of graphite against, let say, Lithium (a li ion cell). That could be interpreted as a Potential of graphite against Li/Li+, and then see how it vary with temperature.
If it can't be quantified it wouldn't be useful, yet there's no end to the virtues extolled over graphite/graphene but never realized. Will someone with ostensible expertise please answer the question, even with ball-park numbers? Certainly allotropes of carbon fit somewhere in the Pauling table.
I would rather start from first principles using Gibbs energy of formation. Since it is zero for pure elements, hence the standard potential - my guess - would be zero as well. That's why vitreous carbon electrodes can be used as working electrodes.
Things must change when you have heavily functionalized carbon, such as graphene oxide or polyphenols.
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