Fitting results using model V for impedance spectra recorded after 48 h exposure in deaerated 0.05 mol dm⁻³ NaCl solution of titanium samples after anodization at 10 and 30 V at 60 °C for 10 min in DES bath composed of choline dihydrogencitrate salt and oxalic acid.

Sample	R s (Ω cm2)	CPEout-T (Ω−1 cm−2 s−P)	CPEout-P	R out (Ω cm2)	C in (F cm−2)	W o			Goodness of fit (χ2)
						W o-R	W o-T	W o-P
Anodized at 10 V	103	1.52 × 10−4	0.677	880aa	8.99 × 10−6	70 184b	0.169	0.39	7.2 × 10−6
Anodized at 30 V	114	1.32 × 10−5	0.764	826	4.38 × 10−6	25 836	0.059	0.43	1.5 × 10−5

^a21% error for this element.

^b2% error for this element.