The fitting result of EIS depicted in Fig. 5c.

		Pure Mg	CM	SiZr	SiZr-G	SiZr-GH
R s (Ω cm−2)		21.91	0.01	1.489	22.79	25.42
R c1 (Ω cm−2)		158.8	91.47	22.78	1.345 × 104	2.186 × 104
CPE1	F cm−2 s1−n	1.261 × 10−5	7.398 × 10−7	2.427 × 10−8	1.526 × 10−6	5.335 × 10−7
	n	0.9389	0.8097	0.9668	0.773	0.8359
R c2 (Ω cm−2)		—	932.6	2595	4305	8021
CPE2	F cm−2 s1−n	—	1.692 × 10−5	5.467 × 10−6	4.969 × 10−5	8.701 × 10−6
	n	—	0.8492	0.87	0.9146	0.8089
C dl (F cm−2)		4.996 × 10−6	2.941 × 10−3	5.973 × 10−3	7.191 × 108	4.28 × 10−5
R ct (Ω cm−2)		35.72	143.3	380.4	6.168 × 106	5294
Chi-squared		1.86 × 10−3	2.53 × 10−4	9.15 × 10−5	8.41 × 10−4	9.87 × 10−4