Table 1.

Summary of prepared samples.

Sample	Substrate	ELD Bath Immersion Time (s)
Ni	Ni layer	30, 60, 90, 120, 150
NiO	NiO layer	90
Si-n	n-type c-Si	30, 90, 180
Si-p	p-type c-Si	30, 90, 180
NiO NWLs	NiO nanowalls	30, 90