Cu₂O/MXene/rGO Ternary Nanocomposites as Sensing Electrodes for Nonenzymatic Glucose Sensors

Abstract

Fine-tuning of the morphology from two-dimensional (2D) to three-dimensional (3D) nanostructures by structural engineering leads to improved biosensing. Herein, a 3D assembly of MXene and rGO nanosheets was synthesized by a hydrothermal process, and then, a naturally abundant and promising biosensing catalyst of Cu2O was added by a coprecipitation method to prepare a 3D ternary composite (MXene graphene aerogel–Cu2O composite). The prepared ternary nanocomposite was characterized by X-ray diffraction, field emission scanning electron microscopy (FE-SEM), Raman spectroscopy, and Brunauer–Emmett–Teller (BET). It exhibited a low crystallite size, spherical-shaped Cu2O, and a large surface area with a porous structure. Further, a sensing electrode was fabricated by the drop-casting method, and then, a chronoamperometric (CA) study was performed to understand the sensing performance of the 3D ternary composite. The fabricated electrode showed sensitivities of 264.52 and 137.95 μA cm–2 mM–1 compared to 2D composites (126.6 μA cm–2 mM–1) with two wide linear ranges of 0.1–14 and 15–40 mM, respectively. The electrode also gave a low detection limit and good stability, selectivity, and reproducibility, thus making it suitable for the determination of glucose levels in human serum samples. These findings reveal that the 3D network of MXene and rGO nanosheets assists in effective charge transfer and promotes the sensing activity of nonenzymatic glucose sensors.

Diabetes Management by Fourth-Generation Glucose Sensors Based on Lemon-Extract-Supported CuO Nanoporous Materials

“…Upon close examination of lower concentrations of glucose and considering that current noise is 0.1 µA cm −2 , a LOD was achieved for 0.01 µM at a signal-to-noise ratio (S/N) of 3. This LOD is on par with those reported for other NEGS techniques (refer to Table 1) [6,[23][24][25][26][27][28][29][30][31]. The presence of multiple substances, such as ascorbic acid (AA), uric acid (UA), dopamine (DPE), cysteine (Cys), and other carbohydrates like fructose (Fru) or galactose, might possibly impact the detection selectivity for determining glucose, especially at higher levels of glucose.…”

“…At a tested potential of −0.53 V vs. Ag/AgCl, the sensor retained approximately 97% of its original current response when exposed to 0.1 mM glucose when immersed in 0.1 M NaOH aqueous solution, indicating the electrode's impressive durability. Porous CuO 0.65 2900 2.5 0.14 [28] CuO@CNTFs 0.6 ~3000 13 mM 1.4 [29] CuO/Ag/NiO 0.65 2895.3 0.001-5.50 mM 0.1 [6] Mesoporous copper (I) oxide nanoparticles -733 1 to 9 mM 0.05 [30] Cu 2 O/MXene graphene aerogel (3D) composite -264.5 0.1 mM-40 mM 1.1 [31] CuO@lemon-extract GCE 0.53 3293 0.01-0.20 µM 0.01 This Work…”

MXene-Embedded Porous Carbon-Based Cu2O Nanocomposites for Non-Enzymatic Glucose Sensors

“…The formed precipitate was allowed to cool to room temperature and centrifuged. The settled precipitate was further washed in ethanol and dried in an oven for 12 h at 50 °C. ,− Similarly, bare Cu 2 O and AC-Cu 2 O composites were prepared without M-AC and with AC, respectively.…”

An ultra-sensitive dopamine electrochemical sensor based on PVP/rGO-MWCNT composites

“…Reduced graphene oxide (rGO) has the advantages of high speci c surface area, excellent electrical conductivity, and good mechanical stability, which makes it a research hotspot in the eld of sensing [18][19][20] . Nonetheless, the surface activity of rGO is weak, leading to the occurrence of accumulation and agglomeration due to the strong van der Waals force between the lamellae.…”