“…Particularly, metallic nano-oxides have attracted considerable attention because of their some significant applications [6][7][8], for example, electrodes made of transition-metal oxides nanoparticles (NPs) demonstrate excellent electrochemical performance [9]. Nickel (II) oxide, one of the relatively few transition metal oxides that tends to be p-type, shows great promise as candidates applied on magnetic material [10], catalytic [11], sensitive material for chemoresistive or optical gas sensors [12][13], optical amplifier and tunable laser [14].…”