The excessive utilization of antibiotics has led to a considerable amount of tetracycline (TC) residues in the water system, giving rise to ecosystem disruption and human health risk. Detecting TC residues through a pragmatic, rapid, and sensitive approach is an imperative need. In this research, a composite fluorescence sensor is combined with the Ti-Fe dual-doped nanoparticles and the sodalite (SOD) structured zeolite. The sensor is assynthesized in a one-pot reaction under the hydrothermal condition, in which the Ti and Fe nanoparticles are uniformly embedded and highly dispersed within the zeolite. With the LOD 0.12 mu M of TC, cyan light can be observed through the sensor. A self-service home testing solution is prepared by mixing a drop of liquid to be tested, milligrams of sensor powders, and several milliliters of ethanol. Under ultraviolet light irradiation, the cyan emission light indicates the presence of TC in the liquid. And the light became stronger with more TC concentration. The sensor demonstrates outstanding stability, repeatability, selectivity, and sensitivity.

Direct glucose alkaline fuel cell (DGAFC) is an efficient energy conversion device that can oxidize the glucose in alkaline electrolytes. The nanosized DGAFC meets well with the desire for non-drug hypoglycemic in the safe treatment of diabetes while a novel catalyst could work in a blood environment. The novel glucose catalyst Cu2O/LTA (Cu2O/Linda A structured zeolite) is designed in the blood sugar environment and as-synthesized in a one-pot reaction under hydrothermal conditions. The Cu2O nanoparticles are generated, dispersed, and restricted in the nanosized opening windows of rigid zeolitic pore channels. The nano-size Cu2O/LTA presents high electrocatalytical activity with a Tafel slope of 125.56 mV dec-1, a current density of 29.39 mA cm-2 and a power density of 411.5 W m-2. The nano-size Cu2O/LTA GCE retains about 98.3 % of its initial current density after the 12-h durability test, which is higher than noble metal glucose catalysts and conventional commercial Pt/C. This excellent glucose oxidation performance is attributed to the synergistic effects of the LTA-structured zeolite nanoscale carrier and the expanded nanoscale Cu2O particles. This work supplies some inspiration for non-drug hypoglycemic with commercially available, easily prepared, non-precious metal nano-catalysts.

Rapid and accurate detection of glutamic acid has always been our focus. Herein, we propose a non-enzymatic electrochemical sensor based on low-cost double transition metal oxides to detect glutamic acid efficiently. In this study, LTA nano-zeolite cages are synthesized by hydrothermal method. To further improve the conductivity, TiO2 and Co metal nanoparticles are combined with nano-zeolite cages with multiple electrocatalytic sites to form TiO2-Co/LTA NPs. Powder X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), energy dispersive X-ray spectroscopy (EDX), scanning electron microscopy (SEM) and high-resolution projection electron microscopy (TEM) were used to characterize the materials before and after adsorption and oxidation of glutamic acid. Cyclic voltammetry (CV), electrochemical impedance spectroscopy (EIS) and differential pulse voltammetry (DPV) were used to test the oxidation and adsorption properties of the modified sensor after adding glutamic acid. Under the optimal pH condition, the sensor detection range is 3.0 x 10(-12)-3.0 x 10(-8) M and the detection limit (LOD) can reach 1.0 x 10(-12) M. In addition, the sensor has good selectivity for glutamic acid, even in the presence of multiple other amino acids. The practical application shows that the sensor can be used to detect glutamic acid in milk, seawater and serum samples with a recovery rate of 90.0 % to 110.0 % and RSD <4 %. We anticipate that this work will provide new ideas for the development of third-generation non-enzymatic sensors for glutamic acid monitoring.

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Acquiring effective, durable and economical non-precious metal electrocatalysts is crucial for the widespread utilization of fuel cells. In this work, an iron/manganese oxide nanocomposite (Fe-MnO@Fe) is synthesized as a novel electrocatalyst by direct-current arc plasma technology integrating transition metal and transition metal oxide. The Fe-MnO@Fe catalyst demonstrates excellent catalytic performance. By modulating the percentage of transition metal and transition metal oxide in the composite, the largest current density values of methanol and ethanol oxidation of the composite reach 20.18 and 7.83 mA cm-2, respectively. In addition, the composite catalyst exhibits excellent stability and conductivity, and the catalyst greatly reduces the experimental cost relative to the noble metal catalysts, indicating that the composite is a potential fuel cell catalyst candidate and provides an innovative concept for creation non-precious metal catalysts.

For glucose sensors, improved sensitivity, accuracy, stability and convenience have always been desired. A novel sensing platform combining CuxO (x = 1, 2) nanoparticles and LTA-structured zeolite well fulfills these requirements and achieves breakthrough sensing concentration (6.0 x 10(-15) M). In hydrothermal conditions, highly dispersed CuxO nanoparticles are formed and restrined in the nano-opening windows of the zeolite surface pores, ultimately yielding CuxO LTA. These in situ-synthesized CuxO NPs have high catalytic activity, while the zeolite provides a stable and rigid framework. This sensor has good selectivity and sensitivity (1.45 mu A mu M-1 cm(-2)) for the determination of glucose under physiological conditions (pH = 7.4) using the DPV method with a limit of detection (LOD) as low as 6.0 x 10(-15) M. The amperometry method exhibited a fast response time of only 0.1 s under strong alkaline conditions (1.0 M NaOH) and achieved a sensitivity of 6.94 mu A mu M-1 cm(-2) and LOD of 2.0 x 10(-9) M. This advanced hybrid sensor system not only provides a wide range of application environments, but also has important implications for the development of low-cost, stable, fast, and efficient non-enzymatic glucose sensors for noble metals. The theoretical support of density-functional theory (DFT) affirms the interaction between zeolite fine structure and glucose molecules.

Heterostructure engineering has been proposed as a promising approach to construct high-efficiency bifunctional electrocatalyst for overall water splitting. Integrated transition metal and metal oxide heterointerfaces with carbon nanomaterials are designed to facilitate electrocatalytic performance toward overall water splitting. Fe/ MnO heterostructures are fabricated on graphene using a one-step DC arc plasma technology. In this way, increased electrochemically active specific areas, accelerated charge transfer, and proper interfacial electronic structure can be achieved. Benefiting from the synergistic effect of multiple materials, fabricated Fe/MnO/graphene heterointerfaces can make the redistribution of electrons between heterointerfaces, which effectively optimizes adsorption/desorption energy of the reaction intermediates. Fe/MnO/graphene delivers excellent catalytic activity with only 362 mV and 339 mV overpotential to reach current density of 10 mA cm(-2) for OER and HER and exceptional long-term stability in alkaline solution. As electrocatalyst at both the cathode and the anode of an alkaline electrolyzer simultaneously, Fe/MnO/graphene electrocatalyst requires a cell voltage of 1.987 Vat a current density of 10 mA cm(-2) for overall water splitting. Therefore, this work offers a feasible route to construct hierarchically nanohybrids as bifunctional electrocatalysts by combining transition metal and metal oxide with carbon nanomaterials.

We have prepared a highly active and stable copper-doped nickel electrocatalyst. Cu/Ni-doped MFI-type protozeolite layered nanoclusters electrodes have a large electrochemically active surface area (ECSA) and good HER activity, as well as excellent durability. The addition of Cu greatly increases hydrogen evolution reaction (HER) activity under acidic conditions. At the same time, the in situ grown Cu2+1O provides some activity, and in addition, the interface constructed between Cu and Ni further generates sufficient electrochemically active surface area. The activated Cu/Ni-doped MFI-type layered nanoclusters required only a 385 mV overpotential to generate 10 mA cm(-2), demonstrating efficient and stable activity with potential practical applications.

The design and synthesis of novel electrode catalysts is an applicable strategy to improve the performance of direct methanol fuel cells (DMFCs). The catalyst is composed of mo- lybdenum disulfide as the shell and nickel silicide-doped sodalite (MoS2/NiSi@SOD) as the core. A series of characterization results indicate that NiSi is highly dispersed in the nanosized SOD cage on the surface of the SOD zeolite at the crystal faces of (011), (102), and (201). A thin conductive protective cover is formed by MoS2 on the surface of the zeolite. By the cyclic voltammetry (CV), the catalyst performs a maximum current density of 46.9 mA cm-2 (1250.1 A gNi-1) with 10 M methanol while no remarkable catalyst poisoning and catalyst deactivation are observed. It is revealed that MoS2/NiSi@SOD under high catalysis activity protects the Ni from the drain in the alkaline electrolyte, leading to a broad application prospect as a noble-metals-free DMFC catalyst.(c) 2023 Hydrogen Energy Publications LLC. Published by Elsevier Ltd. All rights reserved.

The recognition for D and L-Cysteine (Cys) broke through to 0.008 pM by the electrochemistry catalyst Cu Sodalite (SOD) zeolite without enzymes or noble metals. The SOD structured zeolite supplied nanosized SOD cages which are highly consistent with the spatial configuration of cysteine. And the applied electric field magnified the subtle differences in binding energy between D and L-Cys through the highly active Cu catalyst. Under electrochemical aspects, these results manifest themselves as distinguishable current peaks and potential intervals. Unlike the related literature, the sharp and sensitive current peak created by Cu catalyst is set as baseline with the absence of cysteine. With the continually increasing concentration of D or L-Cys, L-Cys shifts to the positive potential, and D-Cys shifts to the negative potential. The result reveals good reproducibility and high specificity that the catalyst is insensitive to other amino acids. The novel catalyst is featured by low cost and high stability, besides higher activity than enzymes.

One of the important factors determining the expansion of the application domain of direct methanol fuel cell (DMFC) is its energy density. The bismuth-nickel doped LTA zeolite was as-synthesized in hydrothermal condition and applied into the electrochemistry catalysis of methanol oxidation reaction (MOR) with high performance in the methanol concen-tration ranging from 0.5 M to 35 M without observed catalyst poisoning. A trace amount of Bi and Ni atoms are highly dispersed on the opening window of the zeolitic surface by the electrochemical rearrangement process. The surface of the LTA structure zeolite is a good carrier for the metal cations with Na cations which could be replaced in hydrothermal crystalline process while the inner direct pores provide a channel for CO gas to escape and prevent catalyst poisoning in electrochemistry progress. Through the comparative study with the Bi doped LTA, Ni doped LTA and the commercial Pt/C catalyst, the Bi and Ni doped LTA reveals higher performance in monatomic catalytic efficiency and electrochemical stability. And through the mutual interaction of diatomic, the doped zeolite material highly improves the energy density of methanol fuel cells and reduces the cost of the cells con-cerning the absence of noble metals.(c) 2022 Hydrogen Energy Publications LLC. Published by Elsevier Ltd. All rights reserved.

A noble metal-free Na Al Si doped libethenite nanoparticle clusters were obtained by applying the method of hydrothermal synthesis. The Linear Sweep Voltammetry (LSV) curve of this nanoparticle cluster electrode shows that there is no noble metal in the hydrogen evolution reaction (HER), and it still exhibits good catalytic activity. The catalytic activity of the libethenite nanoparticle cluster is further enhanced after reduction by the amperometric i-t curve method (A i-t C). The electrochemical performance and catalytic mechanism were investigated by the cyclic voltammetry (CV) method. The characterization analysis by XRD, SEM, TEM, EDS, and XPS found that the catalyst was isomorphous with the natural mineral libethenite, but different from the minerals with Cu and P as the main components in nature when the crystal synthesized under hydrothermal conditions was doped. The heterogenous libethenite nanoparticle cluster framework is replaced by more additional Na, Al, and Si elements. Cu and P elements in the libethenite nanoparticle cluster structure are connected through the mineral framework and uniformly distributed in the crystal structure. This structure increases the electrochemical activity of its HER. Due to the interaction of Cu and P, the catalyst exhibits good catalytic performance for HER under acidic conditions. The reduction by the electrochemical i-t curve reduces the consumption of Cu and enhances the stability of the mineral framework.

The sensitive Sb probe has been anchored in the LTA (Linde Type A) zeolite to form a bifunctional sensor for the electrochemical detection and recycling of sulfadiazine (SDZ) in seawater. Under Amperometric i-t Curve (A i-t C) method, SDZ is quantitatively adsorbed on the Sb LTA zeolite electrode from seawater by adjusting the reduction time and potential. Under differential pulse voltammetry (DPV) method, a characteristic peak is observed at ca. 0.80 V whose intensity can indicate the SDZ concentration on the novel modified electrode. Also, SDZ can be selectively released to phosphate-buffered saline (PBS) in the potential range of 0.80-0.95 V. The electrochemical mechanism of the reversible recovery reaction is carefully studied by the cyclic voltammetry (CV) method and confirmed by the X-ray Photoelectron Spectroscopy (XPS) analysis results related to the interaction between the electrode material and SDZ before and after electrochemical process. Sb doped on LTA zeolite presented a cubic phase from SEM images, and there are some SDZ particles accumulated and adsorbed on the surface of the crystal from TEM images. Theoretical calculation results reveal that SDZ is stable in the electrochemical adsorption and desorption process due to the interaction between the SDZ molecules and the 8 -ring opening windows of LTA zeolite framework. The transfer efficiency of SDZ could reach 9.62 mu g / 100 s or 0.430 g / 1 g based on the mass of Sb probe. The multifunctional sensor suggests a novel strategy for the electrochemically controlled detection and recovery toward antibiotic sulfadiazine.

Acetaminophen (AP) is a commonly used drug that has been detected in groundwater systems in many countries, and has received much attention from researchers in recent years due to its potential environmental impact. In this research, uniformly distributed boron nitride quantum dots (BNQDs) were prepared by a simple ultrasound-solvothermal method. Electrochemical luminescence (ECL) spectroscopy confirmed that BNQDs can act as an effective coreactant to create excellent efficiency in amplifying the ECL intensity of ruthenium-based ECL system. Based on the excited state of Ru bpy 3 2 + ∗ and the energy transfer quenching of AP oxidation products in the luminescent system, an AP concentration-quenched drug sensor was successfully constructed. For this sensor, a wide linear dynamic range and low detection limits (5.0 × 10−7−1.0 × 10−5 mol/L and 4.8 × 10−9 mol/L, respectively) were achieved. This ECL drug sensor has excellent performance in the accurate determination of AP content, relieving the stress of the previous AP detection process, and has good reproducibility and recovery in actual sample measurements.

The accurate and rapid detection for the nucleoside reverse transcriptase inhibitor lamivudine (LAM, 3TC) in cellular systems is always a challenge in the clinic application. Here, a sensitive Cu and Ni nano cluster sensor for LAM is generated under hydrothermal conditions.The Cu and Ni atoms are highly dispersed and aggregated in the nanosized opening pore windows of the synthesized LTA zeolite, through the diatomic synergistic contribution of Cu and Ni and the enrichment of zeolitic channel pores. Using differential pulse voltammetry (DPV), the detection limit (LOD) of LAM at the potential (− 0.15 V) can reach 0.001 pM and the linear range is 0.002 pM–0.002 μM. Since the nano cluster is separated and restricted by the nanosized windows of the zeolite framework, the sensor provides high stability, good recovery (92.5–109

Background: Sulfadiazine (SDZ) is a broad-spectrum antibiotic widely used in aquaculture and animal husbandry and it is easy to remain in the water system to damage the human body. Therefore, detection and removal of sulfadiazine in water systems become critical. Nowadays, catalysts and visible light are used to degrade sulfadiazine into smaller molecules containing N and S to reduce toxicity. However, these small molecules are easily released into water and the atmosphere to be the acid rain. Therefore, it is urgent to design a sensor with the ability to detect and remove SDZ at the same time. (96) Results: We designed a novel composite catalyst sensor (Sb6O13@LTA GCE) with the ability to simultaneously monitor and remove sulfadiazine. The catalyst is generated by introducing SbCl5 into the reactive gel of LTA (Linde Type A) structure zeolite. In the hydrothermal reaction, the corrosive SbCl5 is transferred into nanosized Sb6O13 nanoparticle which is highly dispersed in the opening nano-scaled windows of the zeolite through redox and self-assembled progress. In the selected electrochemical overpotential range, the Sb6O13@LTA composited modified electrode could complete adsorption and desorption of SDZ through the electron transfer from Sb3+ to Sb5+. As the catalyst is in high stability, the only loss in the whole process of recovering SDZ is a small amount of electric energy. The extra-low detection limit and the removal efficiency of Sb6O13@LTA GCE have been achieved 4.0 pM and 19.3 mg/20 mg (136) Significance: The prepared novel sensor has low detection limit, high removal efficiency and high selectivity for sulfadiazine. The Sb6O13@LTA GCE sensor, which is low-cost and has a simple preparation method, exhibits good reproducibility in both seawater and cell fluid. This provides the possibility for wide application in detecting and removing SDZ in water system. (53).

Hydrogen peroxide (H2O2) is widely developed in various fields such as industry, biochemistry, and the environment. A titanium dioxide-doped Linde Type-A (TiO2 LTA) zeolite has been hydrothermally prepared and used as an electrochemical catalyst for the detection of H2O2. The morphology and structure of the TiO2 LTA zeolite were analyzed through a series of characterization tests. Results indicated that the TiO2 was partly and highly dispersed on the zeolitic surface, which improved the catalytic site. Moreover, the zeolite showed good adsorption and adsorbed more H2O2 molecules, improving the sensitivity of detection. H2O2 was measured accurately through the square wave voltammetry (SWV) by the TiO2-doped LTA modified electrode (TiO2 LTA/ GCE). The electrode had the characteristics of a wide detection range, good stability, and good repeatability, with a detection limit (LOD) of 10 nM, linear range of 78.0 nM-19.9 mu M and 96.6-3848.8 mu M. In addition, the sensor has been successfully used for analysis in tap water and cell fluid, which has the potential to become a candidate material for environmental and biological sensing applications.

CuxS derivatives perform high activity in MOR (methanol oxidation reaction) through the co-operation of Cu and S. In order to further improve their performance, the composition and structure are regulated through the co-growth process of copper sulfide heterojunction and SOD (sodalite code) zeolite framework. Under the hydrothermal condition, the intro-duced Cu-0 and Cu+ ions are clustered on the zeolitic surface and inner cages. The S2- anions are selectively located at the zeolite cage to balance the framework charge arisen from the incorporation of Cu+. In the electrochemical process, the optimized Cu2S/SOD zeolite electrode reveals an extra high efficiency of 8847 A g(-1) at an extra low overpotential of 0.374 V with an excellent resistance to catalyst poisoning in high concentration of methanol. This work opens up a new method for the design and industrial application of non-precious metal electrocatalysts with high energy density based on porous zeolite materials. (c) 2023 Hydrogen Energy Publications LLC. Published by Elsevier Ltd. All rights reserved.

The LTA zeolite was coated on the GCE surface. RA was selectively adsorbed on the electrode and reacted on its surface, enhancing the electrochemical signal during the progress of DPV. The DPV results showed a good detection limit and recovery.

To improve the performance of the direct methanol fuel cells (DMFCs), the atomically embedded synergetic dualmetal catalyst nanosized ferrous oxide & molybdenum disulfide @ sodalite structural zeolite (FeO&MoS2@SOD) is designed and generated through self-assemble process under hydrothermal condition. The FeO&MoS2@SOD is characterized by SEM, XRD, TEM, EDX and XPS to reveal its morphology, composition, fine structure, element distribution and element valence, respectively. Its performance in the electrochemical methanol oxidation re-action (MOR) is investigated by EIS, CV and A i-t C with the current density of 24.33 mA cm-2 or 144 mA mg-1, and the power density of 33.99 mW cm-2. The excellent behavior of the obtained catalyst could be ascribed to the synergic effect of the highly dispersed FeO and MoS2 nanoparticles on the surface of the zeolite.