A Hydrogen Peroxide Sensor Based on Pt@Au Nanoparticles Loading to Polyethyleneimine Functionalized Carbon Nanotubes

A facile construction of Ag/MoSe2 composite based non-enzymatic amperometric sensor for hydrogen peroxide

We report an electrochemical non-enzymatic method for hydrogen peroxide (H2O2) detection based on Ag nanoparticle-decorated MoSe2 (Ag/MoSe2-500) hybrid nanostructures. These hybrid nanocomposites are easily prepared by in-situ reduction of Ag+...

Nitrogen-Doped Graphene Oxide Dots-Based "Turn-OFF" H2O2, Au(III), and "Turn-OFF-ON" Hg(II) Sensors as Logic Gates and Molecular Keypad Locks

Fluorescent nitrogen-doped graphene oxide dots (NGODs) have been demonstrated as an on-off nanosensor for the detection of Hg²⁺, Au³⁺, and H₂O₂. As compared to l-cystine, where the luminescence signal recovery results from the detachment of Hg²⁺ from the NGODs, signal recovery through l-ascorbic acid (turn-off-on model) has been attributed to the reduction of Hg²⁺ to Hg⁰. The sustainable recovery of the photoluminescence signal is demonstrated using common citrus fruits containing vitamin C (l-AA), suggesting a promising practical usage of this sensing system. Additionally, the sensitivity of NGOD- and AA-originated signal recovery from the Hg(II)-NGODs mixture has been successfully tested in Hg²⁺ ion-spiked tap water from three different places. Mimic devices were executed and verified on the basis of characteristic spectral changes, and the possible utility of this system in electronic security and memory element devices has also been demonstrated. Considering an easy synthesis process and excellent performance of NGODs, this investigation opens up new opportunities for preparing high-quality fluorescent NGODs to meet the requirements of many applications.

A novel nonenzymatic hydrogen peroxide amperometric sensor based on Pd@CeO2-NH2 nanocomposites modified glassy carbon electrode

Herein, (3-aminopropyl)triethoxysilane functionalized cerium (IV) oxide (CeO₂-NH₂) supported Pd nanoparticles were synthesized. The nanocomposites were characterized using Fourier transform infrared spectroscopy (FTIR), X-ray diffraction (XRD), and High-resolution transmission electron microscopy (HRTEM). The Pd@CeO₂-NH₂ showed better electrocatalytic response to the reduction of H₂O₂ than CeO₂-NH₂. The fabricated sensor exhibited two linear responses to the reduction of H₂O₂. The first one was from 0.001 to 3.276 mM with 0.47 μM of a limit of detection (LOD) (S/N = 3) and excellent sensitivity of 440.72 μA mM^-1 cm^-2 and the second one was from 3.276 to 17.500 mM with the sensitivity of 852.65 μA mM^-1 cm^-2 in the optimum conductions. Also, the sensor exhibited 91% of electrocatalytic activity toward H₂O₂ after having been used for 30 days and the reproducibility was also satisfactory. The sensor response to H₂O₂ was not affected by ascorbic acid, fructose, glycine, dopamine, arginine, mannose, glucose, uric acid, Mg⁺², Ca⁺², and phenylalanine at the studied potential. Also, the fabricated sensor was used to determine H₂O₂ in milk samples. The results show that the constructed sensor can be a promising devise for the determination of H₂O₂ in real samples.