Influence of surface properties and concentration of NiO nanoparticles towards the decoloration of textile dye reactive black 5

Abstract NiO nanoparticles (NPs) were synthesized at various quantities via a thermal decomposition route and analyzed using topographical and optical properties. The average size of NiO NPs is estimated to be between 100 nm and 50 nm, with an average surface roughness of 5.42 nm ± 12.62 nm. Image J analysis suggests that the regularity ratio (R) is between 0.12 % and 0.35 %. NiO NPs with a Ni concentration of 1 mM were able to eliminate 83 % of Reactive Black five during 60 min. Furthermore, when NiO NPs were synthesized at a temperature of 200 °C and at a higher concentration (1 M), they demonstrated excellent adsorption towards the decolorization of RB-5 (RB-5) and obeys pseudo zero order kinetics with values of −0.0106 h −1 , −0.0095 h −1 and −0.0021 h −1 .