•Nickel hexacyanoferrate and Ni-Al LDH film was synthesized by an electrodeposition method.•The composition and morphology of the hybrid film can be adjusted by different strategies.•This modified electrode was used for the electroanalysis of AA.•The proposed sensor was found to be linear, sensitive, selective, precise and accurate.Nickel hexacyanoferrate (NiHCF) and Ni-Al layered double hydroxide (LDH) hybrid film was fabricated on the gold electrode by a two-step electrodeposition method. Varying the strategies of electrodeposition of NiHCF, the hybrid films showed different morphology, composition and electrochemical behavior. As a demonstration, the hybrid film fabricated by using the absorbed Ni2+ on Ni-Al LDH modified gold electrode for the next electrodeposition of NiHCF was used for the electroanalysis of ascorbic acid (AA). The analytical performance of the proposed electrode was investigated by cyclic voltammetry and chronamperometry. The linearity range of AA was from 0.1 to 3.5 mM with a detection limit (S/N = 3) of 21 μM. The developed method was found to be linear, sensitive, selective, precise and accurate. The applicability of the method was confirmed by the satisfactory results in real sample analysis.

A strategy is presented for doping graphene into layered double hydroxide films (LDHs) as a means of improving charge transport of the LDH film in a modified glassy carbon electrode. This result in an enhanced electrocatalytic current for dopamine (DA) and a good separation of the potentials of DA, uric acid and ascorbic acid. Under selected conditions, the square wave voltammetric response of the electrode to DA is linear in the concentration range from 1.0 to 199 μM even in the presence of 0.1 mM ascorbic acid, and the detection limit is 0.3 μM at a signal-to-noise ratio of 3. The method was applied to the determination of DA in pharmaceutical injections with satisfactory results.

A nanocomposite based on layered double hydroxides (LDHs) and gold nanoparticles (AuNPs) was prepared via hydrothermal treatment followed by a reduction procedure. The AuNPs were obtained in Mg–Al LDHs, and they maintained good stability. The electrocatalytic activities of AuNPs/LDH-modified glassy carbon electrodes for methanol oxidation in alkaline medium were investigated in detail. Under the same conditions, the modified electrode exhibited higher electrocatalytic activity than both the pure AuNPs-modified electrode and LDH-modified electrode. The role of the AuNPs and LDHs in this composite system was explored by cyclic voltammetry and chronoamperometry, respectively. Further studies demonstrated that the promoting effect of LDHs could be due to its strong adsorption and partly to the discharge of OH− during methanol oxidation. This work indicates that LDHs is expected to be a good supporting material in the development of methanol anode catalysts.

Glassy carbon electrode modified with boron oxide nanoparticles supported on multiwall carbon nanotubes was obtained via a facile approach. The as-prepared modified electrode exhibits excellent electrocatalytic activity toward the redox of glucose in pH 7.0 phosphate buffer solution. The electrochemical response of the modified electrode to glucose shows a linear range of 1.5–260 μM with a correlation coefficient of 0.9986 and the calculated detection limit is 0.8 μM at a signal-to-noise ratio of 3, which makes it useful for developing the electrochemical determination of glucose concentrations without using glucose oxidase at physiological pH.