Nanoscale resistive switching behaviour and photoabsorption response from NiO nanoflakes

Hydrothermally grown NiO nanoflakes have been investigated here for their resistive switching (RS) and photoabsorption characteristics. The formation and disruption of the conducting filament (CF) under an applied external electric field leads to bistable resistive switching in the grown NiO nanoflakes. Comprehensive investigations of the I–V behaviour show that the formation and rupturing of the CF depend on the concentration of the metallic Ni. Interestingly, photoabsorption response demonstrates a nearly similar behaviour in UV and visible regions for nanoflakes grown at low reaction time, but an enhanced UV response for the flakes obtained at larger reaction times. These nanoflakes displaying multifunctional properties of photoabsorption and RS behaviour, that can be modulated with reaction time, are attractive for optoelectronic, electrochromic and RS-based memory applications.