Synthesis and efficient electrocatalytic performance of Bi2O3/Dy2O3 nanoflakes

Bi 2 O 3 /Dy 2 O 3 nanoflakes with triclinic Bi 2 O 3 and cubic Dy 2 O 3 phases were synthesized by a hexadecyl trimethyl ammonium bromide (CTAB)-assisted hydrothermal route. The Bi 2 O 3 /Dy 2 O 3 nanoflakes were analyzed by X-ray diffraction, X-ray photoelectron spectroscopy, electron microscopy and electrochemical impedance spectroscopy. The size of the Bi 2 O 3 /Dy 2 O 3 nanoflakes with curled surface is about 2 μm and thickness is about 25 nm. X-ray photoelectron spectroscopy confirms the chemical composition of the Bi 2 O 3 /Dy 2 O 3 nanoflakes. The formation process of the Bi 2 O 3 /Dy 2 O 3 nanoflakes was investigated by controlling the CTAB concentration, reaction temperature and reaction time. The formation of the Bi 2 O 3 /Dy 2 O 3 nanoflakes depends on CTAB. The results of cyclic voltammetry (CV) and electrochemical impedance spectroscopy demonstrate good electro-catalytic activity of the Bi 2 O 3 /Dy 2 O 3 nanoflakes towards L-cysteine with a pair of quasi-reversible CV peaks at +0.01 V and –0.68 V, respectively. Bi 2 O 3 /Dy 2 O 3 nanoflakes modified electrode detects L-cysteine linearly over a concentration ranging from 0.001 to 2 mM with a detection limit of 0.32 μM. The proposed nanocomposites modified electrode possesses good reproducibility and stability which can be used as a promising candidate for L-cysteine detection.