Physical Transformation AtlasPTA
Constraint · constraint:nernst-potential-bound

Nernst / Gibbs free-energy bound

Electrical work from a reaction cannot exceed its Gibbs free energy change.

Atlas record: 4 claims reference this constraint — 4 established.

Explorerelations · sources · cite

W_electrical ≤ −ΔG = nFE_cell

4claims0enumerated routes0routes with complete-composition evidence0candidate routes not searched3cited sources

Relations

bounded by · 4
Galvanic (redox) reaction—bounded by→Nernst / Gibbs free-energy boundestablished
Fuel-cell electro-oxidation—bounded by→Nernst / Gibbs free-energy boundestablished
  • 1.23 V reversible potential for H₂/O₂ at 25 °C
Concentration cell effect—bounded by→Nernst / Gibbs free-energy boundestablished
  • E = (RT/zF)·ln(a₁/a₂) per cell — 59 mV per decade of activity ratio at 25 °C — sets the reversible work per unit charge
Photoelectrochemical effect—bounded by→Nernst / Gibbs free-energy boundestablished
  • 1.23 V minimum for water splitting

Cited sources · 3

  1. [1]
    A. J. Bard, L. R. Faulkner. Electrochemical Methods: Fundamentals and Applications (2nd ed.) (2001)
    Wiley · book, no DOI · record
  2. [2]
    A. Fujishima, K. Honda. Electrochemical photolysis of water at a semiconductor electrode (1972)
    Nature 238, 37–38 · doi:10.1038/238037a0 · crossref ✓ 2026-09-19 · record
  3. [3]
    M. Grätzel. Photoelectrochemical cells (2001)
    Nature 414, 338–344 · doi:10.1038/35104607 · crossref ✓ 2026-09-19 · record

Cite this entity

Physical Transformation Atlas (2026). entity constraint:nernst-potential-bound: Nernst / Gibbs free-energy bound. Dataset revision rbfbfcbb70e57 (hash of the canonical data). https://physical-transformation-atlas.wldud5192.workers.dev/e/constraint/nernst-potential-bound

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