Galvanic Replacement 2D — Hollow Nanobox Cross-Section

Reaction Conditions

Au³⁺ concentration 1.0 mM

Temperature 60 °C

ΔE° (Au³⁺/Au − Ag⁺/Ag) 0.94 V

Live Kinetics

Rate constant k0.00

Dissolution prob. / tick0%

Live Reaction State

Ag remaining

100.0%

Au deposited

Ag : Au consumed

— : 1

Interior void

0.0%

Electron bank (3e⁻ reduce one Au³⁺) 0/3

How it works

Galvanic replacement is a redox reaction between a sacrificial metal template and a more noble metal salt in solution. A silver nanocube is more easily oxidised than gold(III), so electrons flow from the silver surface to Au³⁺ ions:

Half-reactions:
  3 × ( Ag(s) → Ag⁺(aq) + e⁻ )     E° = +0.80 V
      Au³⁺(aq) + 3e⁻ → Au(s)        E° = +1.50 V
Overall:
  3 Ag(s) + Au³⁺(aq) → Au(s) + 3 Ag⁺(aq)   ΔE° = +0.70 V (favourable)

Every atom of gold deposited requires exactly three silver atoms to dissolve, because Au³⁺ needs three electrons and each Ag atom only donates one. The simulator enforces this literally: dissolving a surface Ag atom deposits one electron in a bank, and only when the bank fills to 3 is an Au atom placed on the shell.

This view is a 2D cross-section of the same lattice model as the full 3D nanocube: a square grid of Ag sites reacts under an identical cellular-automaton rule (only surface-exposed atoms can dissolve; 4 in-plane neighbours instead of 6), so the corner/edge-first hollowing and 3:1 stoichiometry are exactly preserved — the geometry is thinner, the chemistry is not. The kinetics chart on the right plots Ag remaining and Au deposited live so the effect of each slider is visible as a curve, not just a final snapshot.

Au³⁺ concentration — sets how many oxidant ions are available per step; higher concentration speeds up dissolution (rate ∝ [Au³⁺]).
Temperature — scales the rate through an Arrhenius factor exp(−Eₐ/RT) normalised to 60 °C, just as real electrochemical kinetics do.
ΔE° — the driving-force gap between the two half-reactions; a bigger gap makes every collision more likely to actually transfer charge. (The balanced half-reactions above give ΔE°=+0.70 V at standard conditions — the slider lets you explore how a shifted potential gap, e.g. from a different capping ligand, would change the rate.)

Drag the lattice view to pan, scroll/pinch to zoom — the "Fit view" button re-centres it.

Ag template Au shell (deposited) Vacant / void

drag to pan · scroll to zoom

Ag remaining % Au deposited (scaled)