▎ 摘　　要

A novel and selective method for the fast determination of trace amounts of Ni(II) ions in water samples is described. Method has been developed for preconcentration of Ni on organic-solution-processable functionalized-nano graphene (SPFGraphene) adsorbent in the pH range 5.0-10.0, prior to its spectrophotometric determination, based on the oxidation of bromopyrogallol red at lambda = 517 nm. This method makes it possible to quantitize Ni in the range of 4.2 x 10(-9) to 2.3 x 10(-5) M, with a detection limit (S/N = 3) of 1.42 x 10(-9) M. This procedure has been successfully applied to determine the ultra trace levels of Ni in the environmental samples, free from the interference of some diverse ions. The precision, expressed as relative standard deviation of three measurements is better than 3.0%.