LAUSR

Abstract The novel 3D hierarchical porous wool-ball-like NiO-loaded AlOOH hybrid (NiO/AlOOH-WB) was successfully fabricated through a facile hydrothermal approach followed in-situ growth of NiO nanoparticles (NPs) on AlOOH-WB support. Due to NiO NPs incorporated onto 3D AlOOH-WB surface, which not only increased electroactive area of the electrode but also showed the improved electron transfer rate examined by cyclic voltammetry (CV) and impedance analysis (EIS). NiO/AlOOH-WB/GCE displayed excellent electrochemical performance toward the simultaneous detection of thallium (Tl+), lead (Pb2+) and copper (Cu2+) ions. More importantly, compared with nano AlOOH wire clusters (WC) and nano leafs (LF), 3D hierarchical architecture AlOOH-WB showed excellent electrochemical activity toward targets due to the desirable structural properties. As-fabricated NiO/AlOOH-WB/GCE electrode revealed a higher selectivity and sensitivity towards Tl+, Pb2+ and Cu2+ with a low detection limit (S/N = 3) of 0.028, 0.025 and 0.030 μg/L and a broad linear range (0.1–100.0 μg/L). Furthermore, the fabricated sensor exhibited good stability, satisfactory reproducibility and good application prospect for the electrochemical detection of toxic metal ions individually and simultaneously.