In Situ Synthesis of a Bi2Te3-Nanosheet/Reduced-Graphene-Oxide Nanocomposite for Non-Enzymatic Electrochemical Dopamine Sensing

Abstract

Dopamine is a neurotransmitter that helps cells to transmit pulsed chemicals. Therefore, dopamine detection is crucial from the viewpoint of human health. Dopamine determination is typically achieved via chromatography, fluorescence, electrochemiluminescence, colorimetry, and enzyme-linked methods. However, most of these methods employ specific biological enzymes or involve complex detection processes. Therefore, non-enzymatic electrochemical sensors are attracting attention owing to their high sensitivity, speed, and simplicity. In this study, a simple one-step fabrication of a Bi2Te3-nanosheet/reduced-graphene-oxide (BT/rGO) nanocomposite was achieved using a hydrothermal method to modify electrodes for electrochemical dopamine detection. The combination of the BT nanosheets with the rGO surface was investigated by X-ray diffraction, X-ray photoelectron spectroscopy, field-emission scanning electron microscopy, transmission electron microscopy, Raman spectroscopy, and Fourier-transform infrared spectroscopy. Electrochemical impedance spectroscopy, cyclic voltammetry, and differential pulse voltammetry were performed to analyze the electrochemical-dopamine-detection characteristics of the BT/rGO nanocomposite. The BT/rGO-modified electrode exhibited higher catalytic activity for electrocatalytic oxidation of 100 µM dopamine (94.91 µA, 0.24 V) than that of the BT-modified (4.55 µA, 0.26 V), rGO-modified (13.24 µA, 0.23 V), and bare glassy carbon electrode (2.86 µA, 0.35 V); this was attributed to the synergistic effect of the electron transfer promoted by the highly conductive rGO and the large specific surface area/high charge-carrier mobility of the two-dimensional BT nanosheets. The BT/rGO-modified electrode showed a detection limit of 0.06 µM for dopamine in a linear range of 10–1000 µM. Additionally, it exhibited satisfactory reproducibility, stability, selectivity, and acceptable recovery in real samples.

Ultraviolet-Induced Gas Sensing Performance of Ag/WO3/rGO Nanocomposites for H2S Gas Sensors

“…The D-band is a result of the disorder of carbon materials caused by the presence of sp 3 -hybridized C atoms in the grain boundary and defects. On the other hand, the G-band is attributed to the E 2g vibration of sp 2 carbon atoms. , These bands of WO 3 and rGO are also found in the WO 3 /rGO nanocomposite but slightly shifted toward lower wavenumbers, confirming the successful preparation of the WO 3 /rGO nanocomposite.…”

“…On the other hand, the G-band is attributed to the E 2g vibration of sp 2 carbon atoms. 33,34 These bands of WO 3 and rGO are also found in the WO 3 /rGO nanocomposite but slightly shifted toward lower wavenumbers, confirming the successful preparation of the WO 3 /rGO nanocomposite.…”

Synthesis of Layer‐By‐Layer Decorated Graphene Oxide with Bismuth Telluride Nanoparticles‐modified Dendrimer: Application for Nonylphenol Removal from Aqueous Solutions

“…The intensity of GO-Bi 2 Te 3 decreased, which agrees with the results reported in the Refs. [36,37] As presented in Figure 4c, the characteristic stretching peaks of CÀ N and NÀ H were observed at around 1647 and 1443 cm À 1 , respectively. [38] These peaks are related to 5-ASA.…”

Nanozyme‐Enhanced Electrochemical Biosensors: Mechanisms and Applications

“…The realm of DA detection currently unfurls through the lenses of colorimetry, fluorescence, and liquid chromatography, yet these methodologies traverse an uneven terrain marked by low sensitivity, lackluster selectivity, and the murmur of signal interference. [ 119 ] Inspired by the electroactivity of DA, the pathways for electrochemical detection of DA have been extensively explored. Within this unfolding tableau, Jiang et al.…”