Absolute half-cell entropy

Heat sources in proton exchange membrane (PEM) fuel cells

“…(22) and (20)) leads to the following analytical expressions for the enthalpy and the entropy of H 3 O + solvation (Eqs. (23) and (24), respectively),…”

“…According to the authors, the half-reaction of hydrogen oxidation can be endothermic [25][26][27] (Q a reac < 0) or exothermic [23,24] (Q a reac > 0). A particular attention should be given to the conditions in which these results were obtained: on the one hand, some authors characterized the whole half-reaction of hydrogen oxidation [23,27] or oxygen reduction [25]. On the other hand, others measured the entropy of hydrogen adsorption on Pt/C electrodes [26].…”

Effect of the corrugated bipolar plate design on the self‐humidification of a high power density PEMFC stack for UAVs

“…We shall note that our choice of half-reaction entropies differs from the one recommended in review [107]. The latter is based on older works [108][109][110] that were found incongruous in more recent studies [84,[111][112][113].…”

Meaning and Measurability of Single‐Ion Activities, the Thermodynamic Foundations of pH, and the Gibbs Free Energy for the Transfer of Ions between Dissimilar Materials

“…[ 32 ] Bartmess proposed another approach for defining the standard state of gas-phase electrons and protons that is similar in some respects but different is specific details. [ 33 ] These ideas, together with the method presented herein for determining single-ion activity coefficients, earlier work on partial molar entropies of electrons in metals,[ 34 , 35 ] partial molar entropies of ions in solution,[ 35 ] thermodynamics of work function measurements,[ 36 ] and absolute half-cell entropies[ 37 ] lays the basis for a more complete theory of charged particle thermodynamics that would unify the thermodynamics of gas-phase ion processes with ion-solvation thermodynamics and thermodynamics of ions in condensed phases into a more generalized system of electrochemistry and acid–base chemistry.…”