Struct DiffusionLayer 

pub struct DiffusionLayer {
    pub thickness: f64,
    pub diffusivity: f64,
    pub bulk_concentration: f64,
}

Nernst diffusion layer model.

Models mass-transport limitations across a stagnant diffusion layer.

Fields

thickness: f64

Diffusion layer thickness δ (m)

diffusivity: f64

Diffusivity D (m²/s)

bulk_concentration: f64

Bulk concentration C_bulk (mol/m³)

Implementations

impl DiffusionLayer

pub fn new(thickness: f64, d: f64, c_bulk: f64) -> Self

Create a new DiffusionLayer.

pub fn limiting_current(&self, n_electrons: u32, f_const: f64, area: f64) -> f64

Limiting current density.

j_L = n · F · D · C_bulk / δ

Arguments

• n_electrons — number of electrons transferred per mole of reactant
• f_const — Faraday constant (C/mol)
• area — electrode area (m²)

pub fn concentration_at_surface( &self, current_density: f64, n_electrons: u32, f_const: f64, ) -> f64

Concentration at the electrode surface.

C_s = C_bulk − j · δ / (n · F · D)

Arguments

• current_density — current density (A/m²)
• n_electrons — electrons per mole
• f_const — Faraday constant (C/mol)

pub fn diffusion_overpotential( &self, c_surface: f64, _temp: f64, f_over_rt: f64, ) -> f64

Diffusion overpotential.

η_d = (RT/F) · ln(C_s / C_bulk)

Arguments

• c_surface — surface concentration (mol/m³)
• temp — temperature (K) — kept for API symmetry; used implicitly via f_over_rt
• f_over_rt — F / (R·T) (1/V)