Novel bismuth/multi-walled carbon nanotubes-based electrochemical sensor for the determination of neuroprotective drug cilostazol

A very sensitive electrochemical sensor has been developed by modification of glassy carbon electrode (GCE) with nanoparticles of bismuth (III) oxide (Bi₂O₃) and multi-walled carbon nanotubes (MWCNTs). The sensor was applied for the determination of cilostazol, cyclic nucleotide phosphodiesterase inhibitors in pharmaceutical formulation and human plasma. The voltammetric responses were compared with those obtained at bare GCE under optimum conditions. The cyclic and square-wave voltammograms of cilostazol showed 3.3 and 4.9 times enhancement in the oxidation peak current at MWCNTs–Bi₂O₃/GCE as compared to a bare GCE. Bi₂O₃–MWCNTs/GCE showed a linear response for cilostazol in standard solution over the concentration range of 0.8–13 μg mL⁻¹ with the detection limit 0.76 μg mL⁻¹, whereas human plasma over the concentration range 0.8–12.5 μg mL⁻¹ with the detection limit 0.66 μg mL⁻¹.     

Enhancement of the radiation resistance of cerium-containing fluorophosphate glasses through codoping with Sb2O3 and Bi2O3

The growing demand for radiation-resistant optical glasses for space and nuclear radiation applications has attracted significant research interest. However, radiation-resistant fluorophosphate glasses have been poorly studied. In this work, we report on the tailoring and performance of radiation-resistant fluorophosphate glasses that contained cerium through codoping with Sb₂O₃ and Bi₂O₃. The physical properties, optical properties, microstructure, and defects of fluorophosphate glasses were investigated using transmittance measurements, absorption measurements, as well as Raman spectroscopy, X-ray photoelectron spectroscopy (XPS), and electron paramagnetic resonance (EPR) spectroscopy. The results showed that the radiation resistance of all codoped fluorophosphate glasses was better than the undoped cerium-containing fluorophosphate glasses after 10–250 krad(Si) irradiation. Especially in glasses doped with Bi₂O₃, the optical density increment at 385 nm was only 0.1482 after 250 krad(Si) irradiation. The CeO₂ prevented the development of phosphate-related oxygen hole center (POHC) defects, whereas further codoping with Bi₂O₃ suppressed the formation of oxygen hole center (OHC) and POEC defects, reducing the breaking of phosphate chains caused by CeO₂. Bi³⁺ is more likely than Sb³⁺ to change the valence, affecting the transition equilibrium of intrinsic defects and reducing the concentration of defects produced by irradiation. When codoping with Sb₂O₃ and Bi₂O₃, Bi₂O₃ does not enhance radiation resistance owing to the scission effect of Sb₂O₃ on the phosphate chain, which is not conducive to the radiation resistance of glasses. This indicates that the cerium-containing fluorophosphate glasses doped with Bi₂O₃ can effectively suppress the defects caused by irradiation and improve the radiation resistance of the glasses.     

Effect of yttrium-stabilized bismuth bilayer electrolyte thickness on the electrochemical performance of anode-supported solid oxide fuel cells

Lowering operating temperature and optimizing electrolyte thickness, while maintaining the same high efficiencies are the main considerations in fabricating solid oxide fuel cells (SOFCs). In this study, the effect of yttrium-stabilized bismuth bilayer electrolyte thickness on the electrical performance was investigated. The yttrium-stabilized bismuth bilayer electrolyte was coated on the nickel–samarium-doped composite anode/samarium-doped ceria electrolyte substrate with varying bilayer electrolyte thicknesses (1.5, 3.5, 5.5, and 7.5 μm) via dip-coating technique. Electrochemical performance analysis revealed that the bilayer electrolyte with 5.5 μm thickness exhibited high open circuit voltage, current and power densities of 1.068 V, 259.5 mA/cm² and 86 mW/cm², respectively at 600 °C. Moreover, electrochemical impedance spectroscopy analysis also exhibited low total polarization resistance (4.64 Ωcm²) at 600 °C for the single SOFC with 5.5 μm thick yttrium-stabilized bismuth bilayer electrolyte. These findings confirm that the yttrium-stabilized bismuth bilayer electrolyte contributes to oxygen reduction reaction and successfully blocks electronic conduction in Sm_0.2Ce_0.8O_1.9 electrolyte materials. This study has successfully produced an Y_0.25Bi_0.75O_1.5/Sm_0.2Ce_0.8O_1.9 bilayer system with an extremely low total polarization resistance for low-temperature SOFCs.     

Mn2O3 nanoparticle-porous silicon nanocomposite based amperometric sensor for sensitive detection and quantification of Acetaminophen in real samples

Acetaminophen (AcP) commonly known as paracetamol is the most extensively used non-prescribed medication for the treatment of fever and different kinds of pain. Due to the wide range of use, the determination of AcP contents in commercial tablets, residual AcP present in human blood serum, and the presence of AcP in the environment from the unavoidable leakage during the industrial production becomes crucial. Therefore, we proposed an AcP sensor utilizing a novel Mn₂O₃-embedded mesoporous silicon (Mn₂O₃@PSi) nanocomposite fabricated glassy carbon electrode (GCE). Modern characterization techniques including FESEM, TEM, EDXS, XRD, XPS, and FTIR spectroscopy were employed to characterize the fabricated Mn₂O₃@PSi nanocomposite. XRD and XPS analysis confirmed the fruitful development of nanocomposite consisting of PSi, and Mn₂O₃. TEM images revealed that Mn₂O₃ nanoparticles were randomly distributed onto the PSi matrix. In the electrochemical investigations via the most reliable amperometric technique, the Mn₂O₃@PSi/GCE sensor showed excellent sensitivity (0.7948 μAμM^?1cm^?2), a wide LDR (0.3–138.7 μM), and a very low detection limit (LOD ～0.033 μM). The newly developed AcP sensor was further used to check the potential chemical interference using several closely related chemicals, presenting an extreme selectivity towards the AcP detection. The Mn₂O₃@PSi/GCE sensor electrode was also employed to determine the AcP in commercial paracetamol tablets and showed ～100% quantitative recovery. During the AcP determination, the Mn₂O₃@PSi/GCE sensor also displayed excellent reproducibility, repeatability, and stability. It is anticipated that this Mn₂O₃@PSi/GCE assembly will emerge as an efficient route in developing an effective AcP sensor.     

Electrochemical synthesis of bismuth molybdates with controllable composition and their photocatalytic performance

Bismuth molybdate photocatalysts were controllably prepared via an electrochemical approach at room temperature. The composition and optical property of each product were determined according to the NaOH and Na₂MoO₄ quantities in the electrolyte. Pure Bi_3.64Mo_0.36O_6.55 was prepared at a NaOH concentration range of 0.2‐0.8 mol L^?1, whereas the Bi_3.64Mo_0.36O_6.55/Bi₁₄MoO₂₄ composite was obtained in an electrolyte containing 0.4 mol L^?1 NaOH and 0.5 mol L^?1 Na₂MoO₄. The results of rhodamine B degradation under visible light indicated that Bi_3.64Mo_0.36O_6.55 nanoparticles with a size of 10‐50 nm displayed the best photocatalytic efficiency, which was considerably higher than that of composite one and bulk Bi_3.64Mo_0.36O_6.55.     

Effects of Sb2O3 on the microstructure and electrical properties of ZnO–Bi2O3-based varistor ceramics fabricated by two-step solid-state reaction route

In this work, the ZnO–Bi₂O₃–Cr₂O₃–Co₂O₃–MnO₂ varistors doped with different content of Sb₂O₃ were prepared by two-step solid-state reaction route, including a pre-calcining of the mixtures of nanosized ZnO and the other additives at an optimized temperature, followed by a consequent sintering process at different temperatures. Meanwhile, the effects of Sb₂O₃ on the sintering temperature, microstructure and electrical properties of the objective varistors were investigated. It was found the densification temperature went up in a proper range and the content of pyrochlore phase, spinel phase and β-Bi₂O₃ phase increased with the increasing content of Sb₂O₃, while the grain size of ZnO–Bi₂O₃-based varistor reduced. The results demonstrated that at the same sintering temperature, the second particles increased with the increasing amount of Sb₂O₃, which was helpful to control the grain growth, leading to a higher breakdown voltage. However, the decrease of α-Bi₂O₃ phase (melting point of α-Bi₂O₃ phase is 825 °C), which is the main component of the liquid Bi₂O₃ phase in the sample during sintering process, leads to the increase of the sintering temperature of the green pallet. As a result, the ZnO varistor doped with 3.0 mol% Sb₂O₃ sintered at 1000 °C exhibited the highest breakdown voltage of 1863.3 V/mm. By contrast, the ZnO varistor without Sb₂O₃ doping sintered at 900 °C had the optimum nonlinear coefficient of 59.8.     

Investigations on the electrodeposition behaviors of Bi0.5Sb1.5Te3 thin film from nitric acid baths

The electrochemical reduction process of Bi³⁺, HTeO₂⁺, Sb^III and their mixtures in nitric acid medium was investigated by means of cyclic voltammetry (CV) and electrochemical impedance spectroscopy (EIS) measurements. The reduction products electrodeposited at various potentials were examined using X-ray diffraction (XRD) and energy dispersive spectroscopy (EDS). The results show that cathodic process in the nitric acid solution containing Bi³⁺, HTeO₂⁺ and Sb^III involves the following reduction reactions in different polarizing potential ranges: In low polarizing potential ranges, Te⁰ is formed firstly on the electrode surface through the electrochemical reduction of HTeO₂⁺; with the negative shift of the cathodic polarizing potential, the reduction reaction of Bi³⁺ with Te⁰ to form Bi₂Te₃ takes place; when the cathodic polarizing potential is negative enough, Bi³⁺ and Sb^III react with Te⁰ to form Bi_0.5Sb_1.5Te₃. The results indicate that Bi_0.5Sb_1.5Te₃ films can be fabricated by controlling the electrodepositing potential in a proper high potential ranges.     

Improved electrochemical activity of Bi0.5Sr0.5FeO3-δ–Ce0.9Gd0.1O1.95composite cathode electrocatalyst for solid oxide fuel cells

Developing MIEC materials with high electrocatalytic performance for the ORR and good thermal/chemical/structural stability is of paramount importance to the success of solid oxide fuel cells (SOFCs). In this work, high-activity Bi_0.5Sr_0.5FeO_3-δ-xCe_0.9Gd_0.1O_1.95 (BSFO-xGDC, x = 10, 20, 30 and 40 wt%) oxygen electrodes are synthesized, and confirmed by XRD, SEM and EIS, respectively. The crystal structure, microstructure, electrochemical property and performance stability of the promising BSFO-xGDC composite cathodes are systematically evaluated. It is found that introducing GDC nanoparticles can obviously improve the electrochemical property of the porous composite electrode. Among all these composite cathodes, BSFO-30GDC composite cathode shows the best ORR activity. The peak power density of anode supported single cells employing BSFO-30GDC composite cathode reaches 709 mW cm^?2 and the electrode polarization resistance (R_p) of the BSFO-30GDC is about 0.14 Ω cm² at 700 °C. The analysis of the oxygen reduction kinetic indicates that the major electrochemical process of the GDC-decorated composite cathode is oxygen adsorption-dissociation. These preliminary results demonstrated that BSFO-30GDC is a prospective composite cathode catalyst for SOFCs because of its outstanding ORR activity.     

The effect of antimony trioxide on poly (vinyl alcohol)-lithium perchlorate based polymer electrolytes

A new type of inorganic filler antimony trioxide (Sb₂O₃) is used to prepare composite polymer electrolytes based on poly (vinyl alcohol) (PVA) and lithium perchlorate (LiClO₄) by solution casting technique. The incorporation of Sb₂O₃ enhances the ionic conductivity at ambient temperature and exhibits the highest ionic conductivity value of 9.51×10^?5 S cm^?1 upon the addition of 6 wt% Sb₂O₃. Thermogravimetric analyses (TGA) reveal that the second weight loss is reduced. This shows the improvement in thermal stability of electrolyte film upon addition of Sb₂O₃. Differential scanning calorimetry (DSC) analyses show that the glass transition temperature (T_g) value decreases with incorporation of Sb₂O₃. X-ray diffraction (XRD) studies show that the addition of Sb₂O₃ decreases the degree of crystallinity whereas scanning electron microscope (SEM) studies reveal the surface morphology of the prepared composite polymer electrolytes.     

The effect of Sb2O3 on the properties of micro-arc oxidation coatings on magnesium alloys

Coatings incorporated with Sb₂O₃ were obtained on AZ31B magnesium alloy during micro-arc oxidation (MAO) by adding Sb₂O₃ (0, 2, 4, 6, 8 g/L) into the electrolyte. The voltage of MAO process, microstructure, element distribution, thickness, phase analysis, microhardness, adhesion, and corrosion behavior of the coatings were, respectively, investigated. The results showed that the addition of different concentrations of Sb₂O₃ caused the voltage variation, which resulted in the changes in microstructure, element distribution, and phase composition of coatings, and further led to the improvement of coatings properties. It was found that the addition of Sb₂O₃ could effectively decrease the breakdown voltage, and made the voltage of micro-arc oxidation stage change. Moreover, the presence of Sb₂O₃ influenced surface morphologies of the coatings. Additionally, with the increase in Sb₂O₃, the microhardness of coatings was 155.2, 199.78, 277.34, 267.53, and 127.93 HV, respectively; these were higher than substrate (68.5 HV). Moreover, the addition of Sb₂O₃ effectively improved adhesion. As the Sb₂O₃ increased, the corrosion rate was 2.19 × 10⁻⁴, 9.09 × 10⁻⁵, 4.10 × 10⁻⁵, 2.52 × 10⁻⁴, and 2.96 × 10⁻⁴ mm/a, respectively, and the corrosion resistance increased first and then decreased with the increase in Sb₂O₃. In sum, the optimal Sb₂O₃ concentration was 4 g/L.     

Electrochemical synthesis of belt-like polyaniline network on p-phenylenediamine functionalized glassy carbon electrode and its use for the direct electrochemistry of horse heart cytochrome c

Three-dimension (3D) belt-like polyaniline (PAN) network has been prepared via electrochemical polymerization of aniline on p-phenylenediamine (PDA) functionalized glassy carbon electrode (GCE) using a three-step electrochemical deposition procedure. PDA was covalently binded on GCE via the formation of carbon-nitrogen bond between amine cation radical and the aromatic moiety of GCE surface using electrochemical oxidation procedure. X-ray photo-electron spectroscopy (XPS) and cyclic voltammetry have been performed to characterize the attachment of PDA on GCE. The images of scanning electron microscope (SEM) show that the 3D belt-like PAN network is uniform. The width and thickness of the PAN belt varies in the range of 1.5-5.5 μm and 0.1-0.8 μm, respectively. The distance between the belt-contacts ranges from 2.5 to 15 μm. The 3D belt-like PAN network modified GCE (PAN-PDA/GCE) exhibits an improved electro-activity of PAN at an extended pH up to 7.0. The PAN-PDA/GCE not only immobilizes but also leads to a direct electrochemical behavior of cytochrome c (Cyt c). The immobilized Cyt c maintains its activity, showing a surface-controlled electrode process with the electron-transfer rate constant (k_s) of 14.8 s⁻¹ and electron-transfer coefficient (α) of 0.48, and could be used for the electrocatalytic reduction of hydrogen peroxide (H₂O₂).     

Tin antimony oxide @graphene as a novel anode material for lithium ion batteries

Bimetal oxides have attracted much attention due to their unique characteristics caused by the synergistic effect of bimetallic elements, such as adjustable operating voltage and improved electronic conductivity. Here, a novel bimetal oxide Sn_0.918Sb_0.109O₂@graphene (TAO@G) was synthesized via hydrothermal method, and applied as anode material for lithium ion batteries. Compared with SnO₂, the addition of Sb to form a bimetallic oxide Sn_0.918Sb_0.109O₂ can shorten the band gap width, which is proved by DFT calculation. The narrower band gap width can speed up the lithium ions transport and improve the electrochemical performances of TAO@G. TAO@G is a structure in which graphene supports nano-sized TAO particles, and it is conducive to the electrons transport and can improve its electrochemical performances. TAO@G achieved a high initial reversible discharge specific capacity of 1176.3 mA h g^?1 at 0.1 A g^?1 and a good capacity of 648.1 mA h g^?1 at 0.5 A g^?1 after 365 cycles. Results confirm that TAO@G is a novel prospective anode material for LIBs.     

Effect of ZnBi2O4 and Bi2O3 addition on the densification,microstructure, and varistor properties of ZnO varistors

In this study, 1 wt% Bi₂O₃ (1B), 1 wt% ZnBi₂O₄ (1BZ), and a composite (a mixture of 1 wt% Bi₂O₃ and various amounts (1-4 wt%) of ZnBi₂O₄ ,1B1BZ-1B4BZ) were added to ZnO varistors to investigate the effects of additives on the densification, microstructure, and varistor performance. The results showed that the addition of ZnBi₂O₄ can lower the densification temperature to about 850^oC. When the additive was changed from 1 wt% Bi₂O₃ to 1 wt% ZnBi₂O₄, the α value increased from 42 to 54, the breakdown voltage increased from 775 V/mm to 1011 V/mm, and the leakage current decreased to 0.11 μA. Additions of ZnBi₂O₄ and transition metal cations as donor dopants for the ZnO varistors promote oxygen chemisorption at grain boundaries, resulting in greater α value and lower leakage currents. This suggests the addition of ZnBi₂O₄ can effectively promote densification and improve the varistor properties of ZnO varistors.     

Synergetic tuning of electrical/thermal transport via dual-doping in Bi0.96−xMgxPb0.06CuSeO

The layered oxyselenides BiCuSeO was recently discovered as potential thermoelectric. Our result reveals that the substitute for atom Bi³⁺ by Pb²⁺ & Mg²⁺ in (Bi₂O₂)²⁻ play an important role in electrical transport properties. The maximum electrical conductivity obtained is 460 Scm⁻¹ for Bi_0.84Mg_0.10Pb_0.06CuSeO at RT, highly above the 15 Sm⁻¹ for BiCuSeO. In synergy with low thermal conductivity (0.6-0.4 Wm⁻¹ K⁻¹) and large thermopower (300-500 μVK⁻¹), the highest ZT is achieved about 0.80 at 873 K for Bi_0.88Mg_0.06Pb_0.06CuSeO.     

Improvement of Medical Applicability of Hydroxyapatite/Antimonous Oxide/Graphene Oxide Mixed Systems for Biomedical Application

This study supports the binary and ternary merging tactic, this methodology is useful in the creation of new features that lacked in the parent constituents. Ra develops to reach its peak of 4.25 nm upon HAP/Sb₂O₃/GO which is shadowed by HAP/Sb₂O₃ with 3.87 nm. EDX technique offers quantitative, and qualitative elemental composition of the studied composite, where C, O, P, Ca, and Sb elements records 17.14, 66, 8.7, 7.57, and0.58%, respectively. Consequently, the composition is pure. Also, The BET technique’s resultant surface area is 39.49 for HAP/Sb₂O₃, and 50.76 m²/g for HAP/Sb₂O₃/GO. Additionally, The (HAP/GO, and HAP/Sb₂O₃/GO) ceramic composites microhardness was 3.2?±?0.2 GPa for binary composite, and 3.5?±?0.3 GPa for ternary composite. Thus, GO nano-materials enhance mechanical behavior. Applicably, the merging of the three components in one ternary nanocomposite presents the highest viability with 98.4?±?0.8%, besides the highest antibacterial performance by 15.2?±?0.4 mm for Escherichia coli and 16.1?±?0.5 mm for Staphylococcus aureus.

     

Microstructure and electrical properties of 3-0 type composite of Na0.5Bi2.5Nb2O9-based bismuth-layered piezoceramics

The microstructure and electrical properties of 3-0 type composite of Na_0.5Bi_2.5Nb₂O₉-based bismuth layered piezoceramics modified by Al₂O₃ addition are investigated. The darker and plate-like grains, locating at the grain boundaries, are confirmed to be pure α-Al₂O₃ by high resolution transmission electron microscope, not a Bi₂AlNbO₇ pyrochlore phase. This 3-0 type Na_0.5Bi_2.5Nb₂O₉-Al₂O₃ composite piezoceramics have a large piezoelectric constant d₃₃ of 15.2pC/N with good temperature stability up to 600 °C, and good ferroelectric properties with a relatively large remnant polarization of ~11.6 μC/cm². These demonstrate that designing a 3-0 type composite structure would be an effective approach to tailor the microstructure and improve the electrical properties of bismuth layered piezoceremics for their potential applications at temperature up to 600 °C.     

An experimental study and WinXCom calculations on X-ray photon characteristics of Bi2O3- and Sb2O3-added waste soda-lime-silica glass

Radiation is used in a variety of different fields, and thus protection from its hazardous effects become a popular subject for researchers. For this purpose, in the present study, waste soda-lime-silica glasses as SiO₂–Na₂O–CaO–Bi₂O₃ and SiO₂–Na₂O–CaO–Sb₂O₃ were investigated for X-rays photon characteristics in the energies of 0.01–0.1 MeV via WinXCom program, and the results were compared with the experimental findings obtained at 0.04 MeV. Waste packaging glass was evaluated by adding varying amounts (0.005, 0.05, and 0.5 percentages) of Bi₂O₃ and Sb₂O₃. Seven different glass batches were prepared by following the procedures of precisely weighing the relevant amounts to obtain 10 g specimen in total, homogeneously mixing the respective contents, and thoroughly melting in an Au–Pt crucible via conventional electrical furnace at 1250 °C for 4 h. The linear attenuation coefficient (LAC) for glass specimens were experienced at 0.04 MeV, and it was found out that increasing contents of both oxides increased the LAC implying that a decrease in X-ray transmission occurred. From the point of WinXCom calculations, the LAC and mass attenuation coefficient (MAC) increased while half value layer (HVL) and mean free path (MFP) thicknesses decreased as the oxide substances increased in the glass specimens. That is, Sb₂O₃ addition provided higher X-rays attenuation characteristics in comparison to Bi₂O₃ additive. Further, the experimental data at 0.04 MeV were compared with WinXCom calculations, and it was figured out that the data were parallel for each other, but the correlation coefficient (R²) was found as 0.15 which means that the values were in loose agreement.     

Middle-low temperature sintering and piezoelectric properties of CuO and Bi2O3 doped PMS-PZT based ceramics for ultrasonic motors

A ternary solid-solution piezoelectric ceramic of rare-earth oxides modified 0.03 Pb(Mn_1/3Sb_2/3)O₃-0.97 Pb(Zr_0.505Ti_0.495)O₃ + x wt.% CuO + y wt.% Bi₂O₃ (PMS-PZT + x wt.% CuO + y wt. % Bi₂O₃) (x, y = 0–0.2) was successfully prepared via a transient-liquid-phase sintering. Both Cu²⁺ and Bi³⁺ were believed to replace the A-site Pb ions and to evidently induce the lattice shrinkage and the distortion decrease. However, the addition of only a small amount of CuO was found to effectively reduce the sintering temperature, sustain good piezoelectric properties and predominant transgranular fracture modes, but obviously increase the average grain size and high-field dielectric loss. Further experimental results indicate that the grain growth of the ceramics was inhibited effectively and the high-field dielectric loss was reduced through CuO and Bi₂O₃ co-doping. The 0.05 wt% CuO and 0.15 wt% Bi₂O₃ co-doped PMS-PZT ceramics sintered at 1050 °C exhibit excellent dielectric and piezoelectric properties of d₃₃ = 410 pC/N, k_p = 0.62, Q_m = 1478, ε_r = 1550, tan δ = 0.8% (400 V/mm) and T_c = 330 °C. The experimental results can provide a solid fundament for multilayer piezoelectric actuating devices.     

One-step microwave-assisted synthesis of Sb2O3/reduced graphene oxide composites as advanced anode materials for sodium-ion batteries

Sb₂O₃/reduced graphene oxide (RGO) composites were prepared through a facile microwave-assisted reduction of graphite oxide in SbCl₃ precursor solution, and investigated as anode material for sodium-ion batteries (SIBs). The experimental results show that a maximum specific capacity of 503 mA h g⁻¹ is achieved after 50 galvanostatic charge/discharge cycles at a current density of 100 mA g⁻¹ by optimizing the RGO content in the composites and an excellent rate performance is also obtained due to the synergistic effect between Sb₂O₃ and RGO. The high capacity, superior rate capability and excellent cycling performance of Sb₂O₃/RGO composites demonstrate their excellent sodium-ion storage ability and show their great potential as electrode materials for SIBs.     

One-pot green hydrothermal synthesis of bio-derived nitrogen-doped carbon sheets embedded with zirconia nanoparticles for electrochemical sensing of methyl parathion

We report a simple, economical and green one-pot hydrothermal strategy to synthesize the bio-derived nitrogen-doped carbon sheets (ONCSs) embedded with zirconia nanoparticles (ZrO₂NPs) with orange juice as carbon source and solvent. The ONCSs-ZrO₂NPs composite was further applied in the decoration of glassy carbon electrode (GCE) for electrochemical sensing of methyl parathion. The orange juice-derived ONCSs with graphene-like micromorphology showed good electrical conductivity, large specific surface area, and nitrogen functional groups. They could accelerate the electron transport, provide sufficient electrolyte-electrode interface, and improve the surface wettability, thus forming a suitable microenvironment for the redox reaction of MP. The embedded ZrO₂NPs in graphene-like ONCSs possessed a strong affinity toward the phosphorus groups on MP molecules, which could promote the preconcentration of MP in the interface of the fabricated sensor and electrolyte. Benefitting from the synergistic effect of ONCSs and ZrO₂NPs/GCE, the ONCSs-ZrO₂NPs/GCE sensor exhibited excellent peak current response towards MP with a linear detection range of 0.01–15 μg mL⁻¹ and a low detection limit of 0.115 ng mL⁻¹. Furthermore, the ONCSs-ZrO₂NPs/GCE sensor presented good capability to investigate the MP levels in romaine and kiwifruit juices with satisfactory recoveries. This work provides a novel and green one-step approach in the development of carbon-based composite materials for high-performance MP electrochemical sensors.