. 2019 Sep 27;10:4394. doi: 10.1038/s41467-019-12277-4

Table 1.

Combination of three different techniques for porosity determination in thin porous layers

Technique	QCM-D/air	QCM-D/hydrodynamic	QCM/viscoelastic	RBS	GISAXS
Equation	ϕ = [1 − (m_p/h_pρ_np)]	ϕ = m_liq/ρ_liqh	ϕ = (1 − ρ_p/ρ_np)	ϕ = (1 − ρ_p/ρ_np)	ϕ = 1 − (α_p/α_np)²
Porosity/%	37.04 ± 1.81	36.60 ± 2.45	37.15 ± 2.18	36.42 ± 2.15	36.83 ± 1.80

The natural parameters of the porous/viscoelastic structure of the alloys captured by each technique are indicated together with equations for the nanoporosity calculation. The determined values of porosity are listed in the bottom line