Oxide Composites Research Articles

Effect of doping with iron and cations deficiency in the high conductive electrolyte La0.8Sr0.2Ga0.8Mg0.2O3–δ on oxygen exchange kinetics

The oxygen isotope exchange method was used to investigate the kinetics of the interaction between gaseous oxygen and LaGaO3-based oxides in a temperature range of 650 to 850 °C, with an oxygen pressure of 10 mbar. The stable isotopes of 18O/16O were used as labelled ions. The temperature dependencies of the heterogeneous oxygen exchange rate (rH), the oxygen dissociative adsorption rate (ra), the oxygen incorporation rate (ri), and the oxygen diffusion coefficient (D) were determined. A comparative analysis of the rH and D values for La0.8Sr0.2Ga0.8Mg0.2O3–δ was carried out with a view to identifying any similarities or differences when compared with the literature data on oxides with similar compositions. The effect of FeGa′ doping and the creation of an A-sublattice deficiency on the kinetic characteristics were investigated using the (La0.8Sr0.2)0.98Ga0.7Fe0.1Mg0.2O3–δ oxide as a case example. Correlations between the rate-determining step of oxygen exchange and the modification of the oxide composition were identified.

Dicyandiamide Applications Mitigate the Destructive Effects of Graphene Oxide on Microbial Activity, Diversity, and Composition and Nitrous Oxide Emission in Agricultural Soil.

The widespread production and utilization of graphene oxide (GO) raise concerns about its environmental release and potential ecological impacts, particularly in agricultural soil. Effective nitrogen (N) management, especially through nitrification inhibitors like dicyandiamide (DCD), might mitigate the negative effects of GO exposure on soil microbes via N biostimulation. This study quantified changes in soil physicochemical properties, nitrous oxide (N2O) emissions, microbial activity, biomass, and community after treatments with GO and DCD. The GO exposure significantly reduced bacterial 16S rRNA gene abundance and the biomass of major bacterial phyla. It also stimulated pathways linked to human diseases. However, DCD application alleviated the negative effects of GO exposure on soil bacterial biomass. While DCD application significantly reduced soil N2O emission, the GO application tended to hinder the inhibiting performance of DCD. Our findings highlight the hazards of GO exposure to soil microbes and the potential mitigation strategy with soil N management.

Effect of Dietary Short-Chain Fatty Acids on the Immune Status and Disease Resistance of European Seabass Juveniles

(1) Background: This study aimed to evaluate the potential of short-chain fatty acids as functional ingredients to improve the immune status and disease resistance of European seabass (Dicentrarchus labrax) juveniles. (2) Methods: For that purpose, triplicate groups of fish with an initial body weight of 15.2 ± 0.03 g were fed isoproteic (43% crude protein) and isolipidic (18% crude lipids) diets supplemented with sodium acetate (SA), sodium propionate (SP), and sodium butyrate (SB) at two inclusion levels: 0.25% and 0.50%. An unsupplemented diet was used as a control. After 56 days of feeding with the experimental diets, fish were intraperitoneally (i.p.) injected with 100 µL of Vibrio anguillarum (1.2 × 107 Colony Forming Units (CFU)/mL) and mortality was recorded for 3 weeks. At the end of the trial, there were no differences in survival between the treatment groups and the control, but survival was higher in fish fed the diet supplemented with SB 0.50 than SP 0.25 (93.3 vs. 66.7%). Compared to the pre-challenge values, and regardless of diet composition, all hematological parameters (hemoglobin, hematocrit, red blood cells, white blood cells) measured decreased after 4 h of bacterial challenge, except for neutrophils which were increased. Independently of diet composition, lysozyme and nitric oxide decreased at 4 and 24 h post infection. Compared to the control, diets supplemented with SA and SP promoted an up-regulation of both pro- and anti-inflammatory cytokines at 4 h after the challenge, while the diets supplemented with SB promoted an up-regulation of pro- and anti-inflammatory cytokines at 24 h after the challenge. (3) Conclusions: Overall, present results suggest that SA and SP provide a fast response to a bacterial challenge in European sea bass juveniles, while SB provides increased survival.

Application of composite persulfate oxidation to remediate weathered lubricating oil-contaminated soils: Batch and pilot-scale studies

In this study, two novel composite persulfate (PS) oxidants [base pulverized NaOH composite persulfate (BPS) and metal (iron and manganese) composite persulfate (MPS)] were developed. The feasibility, mechanisms, and optimal conditions for remediating weathered lubricating oil (WLO)-contaminated soils using composite PS oxidants were evaluated. BPS was prepared by blending PS and NaOH powders (molar ratio = 1:0.3), while MPS was prepared by mixing PS, FeCl2, and KMnO4 at a molar ratio of 1:0.3:0.05 for PS:Fe:Mn. The oxidation of rhodamine B (RhB) dye using BPS and MPS followed second-order kinetics. MPS process was more effective in organic oxidation, likely due to its electron transfer mechanism. The generation of •SO4- in the BPS process required activation by •OH, potentially leading to more efficient and stable •SO4- generation and subsequent organic chemical oxidation. Radical analyses revealed that •SO4- was present in the pH range of 3–12, with the strongest •OH signal at pH 7–9. Employing hybrid BPS and MPS for WLO-contaminated soil remediation could achieve optimal TPH removal efficiency due to the combined generation of •OH (high reactivity) and •SO4- (stable characteristics). The addition of BPS helped neutralize acidified soils and maintained a higher soil pH (around 6.1). The multi-stage oxidation using the hybrid composite PS oxidants (MPS + BPS) at a 1:1 ratio (w/w) achieved 84 % TPH removal (initial TPH = 7721 mg/kg) after three oxidation stages (5 % w/w oxidant dosage). The composite oxidation process offers a more reactive oxidation potential with an extended oxidant life without causing a substantial pH drop.

Construction of a Bifunctional Nanoelectrode for Intracellular Natural Product Delivery and Monitoring Anticancer Efficiency in Single Cells.

Natural products play a significant role in new drug discovery and anticancer therapy, making the evaluation of their anticancer efficiency crucial for clinical application. However, delivering natural products to single cells and in situ monitoring of induced signaling molecule fluctuation to evaluate anticancer efficiency remain significant challenges. Hence, we proposed a universal and straightforward strategy to construct a bifunctional nanoelectrode that integrates drug loading and monitoring of signal molecule fluctuations at the single-cell level. Platinum (Pt) nanoparticles/reduced graphene oxide (rGO) composites were first electrochemically deposited on the carbon fiber nanoelectrode (CFNE@Pt/rGO) to serve as electrocatalytic materials for the monitoring of natural-product-induced reactive oxygen species (ROS) generation. The GO/natural product complex, formed by π-π stacking and hydrophobic interactions, was further electrochemically reduced on the surface of CFNE@Pt/rGO to enable the CFNE drug-loading function. Using this bifunctional functional nanoelectrode, a series of natural products (such as capsaicin, curcumin, and chrysin) were delivered into single cancer cells, and their anticancer efficiency was evaluated by measuring ROS generation. The results showed that intracellular ROS production induced by chrysin was 1.5-fold greater than that of curcumin and 2.1-fold greater than that of capsaicin. This work proposes an effective tool to evaluate the anticancer efficiency of various natural products. Additionally, this nanotool can be expanded to monitor the fluctuation of other biomolecules (such as RNS, GSH, NADH, etc.) by replacing Pt nanoparticles with other electrocatalytic materials, which is significant for comprehensively exploring the anticancer efficiency of new drugs and for the clinical treatment of various diseases.

Green Synthesis of Clay/rGO Composite for Sensitive Detection of Para Nitrophenol in the Environment

AbstractNitrophenols (e. g., para nitrophenol), although they have beneficial properties, their residuals are injurious to the environment owing to their high lethal potential for many categories of nature (e. g. animals, humans, plants, etc.), which require their monitoring. In this paper, a new Clay/green reduced graphene oxide composite (Clay/rGO) was efficaciously synthesized and utilized as an excellent modifier for carbon paste electrode (CPE) for the electro‐analytical determination of paranitrophenol (PNØ). The electrochemical futures and reduction of PNØ at the surface of the as‐prepared Clay/rGO˧CPE have been executed using DPV differential pulse voltammetry (DPV), cyclic voltammetry (CV) and electrochemical impedance spectroscopy (EIS). The use of the EIS provided that the Clay/rGO˧CPE facilitate the electron exchange process. By using the DPV technique in phosphate buffer (PB) under biological pH (7) (PB_7) the prepared monitor exhibited an excellent linearity relationship in the concentration ranges from 1.0 to 1000.0 μM with a detection limit (DL=3×σ/P) of 0.16 μM and a quantification limit of (QL=10×σ/P) of 0.54 μM. The Clay/rGO˧CPE offered high selectivity and a satisfactory concert in the electroanalytical sensing of PNØ in wastewater sample.

Mineral Composition and Distribution of Silt and Oxides in Shatt Al-Arab Deposits, Basra, Iraq

Understanding the mineral composition and distribution of river deposits is crucial for environmental management, resource utilization, and geological studies. This study aims to investigate the mineral composition and distribution of silt and oxides in the deposits of the Shatt al-Arab River, specifically in the Faw area of Basra Governorate. Samples were collected from depths of 0-30, 30-60, and 60-90 cm. The silt fraction (2-53 micrometers) was isolated, and mineral analysis was conducted using XRD and a point-counting device. Morphological characteristics were determined using a polarized light microscope. XRD analysis revealed the presence of minerals such as quartz, calcite, dolomite, smectite, kaolinite, chlorite, illite, hematite, magnetite, and albite at varying depths. Polarized light microscopy identified additional minerals within light and heavy fractions. The study found a dominance of monocrystalline quartz and opaque minerals, with magnetite being more prevalent than hematite across all depths and a high correlation coefficient with depth (0.96). Depth-specific variations in mineral composition suggest the need for further research in different locations and at greater depths. These findings provide insights into sedimentary processes and potential resource utilization in the region, making this study significant for regional geological and environmental research. Future research should focus on the temporal changes in mineral composition and their impact on sediment dynamics to enhance the understanding of regional geological history and resource management.

Revealing Microstructure and Enduring Properties of Settled Barite Extracted from an Offshore Well Two Decades Later: Well Abandonment and Slot Recovery

Summary Barite settling in the annulus behind the casing is an undesired yet common occurrence during the life of a well. Over time, the drilling fluid left in the annulus settles, leaving behind solidified barite that can hinder slot recovery and plug and abandonment (P&A) operations by impeding the cut and pull process. During a P&A operation, Equinor acquired settled barite samples from a North Sea well where the casing was held back by these weighting agents, introducing overpull and prolonging the cut and pull operation. A laboratory analysis program that included determination of the particle-size distribution (PSD), electrokinetic potential of particles (zeta potential), crystallography [X-ray diffraction (XRD)], chemical composition [X-ray fluorescence (XRF)], thermogravimetric analysis (TGA), and microstructure [scanning electron microscopy (SEM), energy-dispersive X-ray spectroscopy (EDS), and quantitative evaluation of materials by scanning electron microscopy (QEMSCAN)] was carried out on these settled barite samples to understand their properties. The results of this study provided valuable insights into the composition and characteristics of the settled material in the annulus. The solidified barite within the annular space exhibited no signs of chemical reactions. XRD analysis confirmed the barite to be the sole predominant solid in the solidified material, aligning with expectations. However, additional analytical techniques, including XRF, QEMSCAN, and EDS, detected interconnections between barite particles, primarily facilitated by iron or quartz particles. Additionally, trace amounts of calcite, iron oxide, and mixed compositions involving Si, S, Fe, Ba, O, and Cl were identified within the solidified material. SEM results indicated that the particles exhibited strong compaction characteristics but lacked cementation, retaining some porosity. Notably, the absence of bentonite or other clays was consistently observed in all analyses. This study highlights the process of solidification observed in settled barite, suggesting that factors other than chemical reactions may be responsible for this phenomenon. The potential mechanisms contributing to solidification include physical aggregation, compaction, and alterations in surface charge under downhole conditions. This enhanced understanding of the solidification process will contribute to the development of solutions for efficient casing removal and even the usage of settled barite as a barrier material.

Thermally Stable Pt Clusters Anchored on Mg–Al–Ti Composite Metal Oxide for Efficient Cycloalkane Dehydrogenation

Thermally Stable Pt Clusters Anchored on Mg–Al–Ti Composite Metal Oxide for Efficient Cycloalkane Dehydrogenation

K+ doped graphitic carbon nitride modified layered double oxide nanocomposite towards high-efficiency CO2 adsorption at intermediate temperature

As a novel medium-temperature CO2 adsorbent, K+ doped and graphitic carbon nitride modified layered double oxide composite (xK/CN-LDO, x = 15, 20, and 25 wt%) were prepared via in-situ synthesis and impregnation methods. Their adsorption performance was evaluated by thermal gravimetric analyzer. g-C3N4-modified LDO (CN-LDO) exhibited a CO2 adsorption capacity of 0.46 mmol/g, 1.39 times higher than the 0.33 mmol/g observed for LDO. This enhancement was attributed to the increased specific surface area and the exposure of additional extractable sites. Further doping with K significantly enhanced the adsorption uptake of xK/CN-LDO. Notably, 20 K/CN-LDO achieved the highest CO2 adsorption uptake of 0.82 mmol/g, representing a 2.48-fold increase compared to LDO. This further enhancement can be ascribed to K's ability to alter the distribution of chemical adsorption sites, thereby providing an optimal number of basic sites. In-situ DRIFTS analysis revealed that CO2 predominantly existed in the form of carbonate species, while adsorption kinetics studies show that the dominant mechanism is chemical adsorption, with external diffusion being the primary adsorption process. Furthermore, 20 K/CN-LDO exhibited significantly higher regeneration efficiency of 72.4 % after 10 cycles, showcasing its promising practical prospects for application in the SEWGS process.

Novel composite of nano zinc oxide and nano propolis as antibiotic for antibiotic-resistant bacteria: a promising approach

This study proposes an innovative approach to combat the escalating threat of antibiotic resistance in bacteria by introducing a novel ZnO-propolis nanocomposite (ZnO-P NCs). The overuse of antibiotics, particularly during events like the COVID-19 pandemic, has intensified bacterial resistance, necessitating innovative solutions. The study employs a cost-effective and controllable biosynthesis method to produce ZnO nanoparticles (ZnO-NPs), with propolis extract crucially contributing to the reduction and stabilization of Zn2+ ions. A biodegradable nano-propolis matrix is then created by incorporating ZnO-NPs, forming the ZnO-P NCs. Structural stability is confirmed through FT-IR and Zeta potential analysis, while nanoscale properties are validated via TEM, SEM, and XRD analyses. The antimicrobial efficacy of various substances, including propolis, nano propolis, ethanolic propolis extract, ZnO-NPs, and ZnO-P NCs, is assessed against Gram-negative and Gram-positive bacteria, alongside a comparison with 28 antibiotics. Among the bacteria tested, Pseudomonas aeruginosa PAO1 ATCC15692 was more sensitive (40 mm) to the biosynthesized nanocomposite ZnO-P NCs than to ZnO-NPs (38 mm) and nanopropolis (32 mm), while Escherichia coli was resistant to nanopropolis (0 mm) than to ZnO-NPs (31 mm), and ZnO-P NCs (34 mm). The study reveals a synergy effect when combining propolis with green-synthesized ZnO-NPs in the form of ZnO-P NCs, significantly improving their efficiency against all tested bacteria, including antibiotic-resistant strains like E. coli. The nanocomposite outperforms other materials and antibiotics, demonstrating remarkable antibacterial effectiveness. SEM imaging confirms the disruption of bacterial cell membranes by ZnO-NPs and ZnO-P NCs. The study emphasizes the potential applications of ZnO-NPs integrated into biodegradable materials and underscores the significance of the zinc oxide-propolis nanocomposite in countering antimicrobial resistance. Overall, this research offers a comprehensive solution to combat multidrug-resistant bacteria, opening avenues for novel approaches in infection control.

Efficient cascade reactions involving esterification, hydrogen transfer, and lactonization for biomass conversion using MOF/Metal oxide composites as heterogeneous catalysts

Development of heterogeneous catalysts with both Brønsted and Lewis acid properties has proved to be promising and useful because they offer an efficient way to cascade reactions. In this study, we present the synthesis pathway and efficacy evaluation of new composites which combined by sulfonic acid functional group modified TiO2 and MIL-101, analyzing their structure-performance correlation as heterogeneous catalysts in cascade reactions involving esterification, hydrogen transfer, and lactonization. These composites possess an open porous structure (MOF and porous TiO2), as well as active sites including Lewis acid (unsaturated coordination metal), Lewis base (Ti-OH), and Brønsted acid (-SO3H). The role of these active sites and the synergies between them were investigated through the esterification of levulinic acid and the direct synthesis of γ-valerolactone from levulinic acid and furfural under cascade reactions. The composites exhibit a 100% ethyl levulinate (EL) yield at 120°C for 6 hours, with γ-valerolactone yields reaching up to 94.5% (160 °C, 9 h) and 89.5% (160 °C, 16 h) from levulinic acid and furfural, respectively. This synergistic effect of Lewis acid/base and Brønsted acid ensures efficient esterification. The presence of a sulfonic acid group promotes the lactonization reaction, while the Meerwein-Ponndorf-Verley reduction is facilitated by the dual Cr sites located adjacent to each other in the secondary building unit of MIL-101(Cr). Moreover, the double-porous structure of porous TiO2 and MIL-101(Cr) effectively guarantees the efficient mass transfer of reactants and intermediates, leading to enhanced synergistic effects that promote more efficient reaction conversion.

Mechanism of Anodic Dissolution of Tungsten in Sulfate–Fluoride Solutions

Thin passive films on tungsten play an important role during the surface levelling of the metal for various applications and during the initial stages of electrochemical synthesis of thick, nanoporous layers that perform well as photo-absorbers and photo-catalysts for light-assisted water splitting. In the present work, the passivation of tungsten featuring metal dissolution and thin oxide film formation is studied by a combination of in situ electrochemical (voltammetry and impedance spectroscopy) and spectro-electrochemical methods coupled with ex situ surface oxide characterization by XPS. Voltametric and impedance data are successfully reproduced by a kinetic model featuring oxide growth and dissolution coupled with the recombination of point defects, as well as a multistep tungsten dissolution reaction at the oxide/electrolyte interface. The model is in good agreement with the spectro-electrochemical data on soluble oxidation products and the surface chemical composition of the passive oxide.

Experimental, simulation, and theoretical investigations of gamma and neutron shielding characteristics for reinforced with boron carbide and titanium oxide composites

This study investigates the radiation shielding properties of composites containing polyester resin, boron carbide and titanium oxide in varying proportions. The radiation transmittance of the produced composites was measured using radioactive sources 241Am, 137Cs, 133Ba, 60Co, and 22Na across a photon energy range of 59.5 keV–1332.5 keV. To analyze radiation permeability, experimental geometry was simulated using Monte Carlo-based computer codes Monte Carlo N-Particle (MCNP), Particle and Heavy Ion Transport code System (PHITS) and FLUktuierende KAskade or Fluctuating Cascade (FLUKA), and the experimental data were compared with simulation results and theoretical data obtained from WINXCOM. The findings demonstrated a high degree of consistency between experimental, simulation, and theoretical results. Notably, the BCTiO50 sample, which included a 50% addition of TiO2, emerged as the most effective in photon radiation shielding. In addition to gamma shielding, the neutron shielding properties of the produced composites were evaluated using the FLUKA code, revealing that the BCTiO0 sample, with the highest percentage of boron, provided the best neutron shielding. This analysis included composites with decreasing boron carbide content by 10%, 20%, 30%, 40%, and 50% by weight, each replaced with titanium oxide, showcasing the potential applications of these polymer composites in radiation shielding.

Improvement on the onset voltage for electroluminescent devices based in a SiOx/SiOy bilayer obtained by sputtering

Abstract This work is focused on the composition, optical and electroluminescent properties of silicon rich oxide (SiOx, x < 2) films monolayers and bilayers (SiOx/SiOy) deposited by Sputtering with silicon excess between 6.2 to 10.7 at.% were deposited on p-type (100) silicon substrates. As-deposited SiOx films emit a broad photoluminescence (PL) band where the maximum peak shifts from 420 to 540 nm as the Si-excess increases from 6.2 to 10.7 at.%, respectively. The PL intensity strongly increases and the main PL peak shifts to the red region when the SiOx films are thermally annealed. The PL emission band was dependent on silicon excess and the presence of Si-O bonds defects working as emission centers. MOS-like devices were fabricated (N+ polysilicon was used as top contact and aluminum as bottom contact) to study the EL of SiOx monolayers and SiOx/SiOy bilayers. It was found that the required voltage to obtain EL was reduced when SiOx/SiOy bilayers were used in light emitting capacitors (BLECs) as compared to those with SiOx monolayers.

On the synthesis and formability of high-entropy oxides

This paper reports on a straightforward and general solution-based synthesis method for high-entropy oxides (HEOs) of different types and compositions. The flexibility and simplicity of this method are hoped to drive development of new HEOs and study of their properties and applications. Thirteen HEOs with rock salt, fluorite, spinel, and perovskite structures were synthesized using a Pechini-type synthesis at temperatures significantly lower than those necessary in solid-state synthesis (400–900 °C). Metal nitrates, nitrites, chlorides, and even water-sensitive alkoxides were used as the metal precursors with the present method. The HEOs were characterized using powder X-ray diffraction, scanning electron microscopy, and energy-dispersive X-ray spectroscopy. Relaxation of cation size and charge rules and formability of HEOs are also discussed. The present results indicate that the classical criteria for material stability do not readily translate to high-entropy systems. For example, the well-known criteria for Goldschmidt and octahedral tolerance factors established for ordinary perovskites do not seem to describe formability of perovskite HEOs well. The discussed relaxation of cation size and charge rules will contribute to the understanding of HEO systems and development of new HEO phases.

Preparation of nano SnO2-Sb2O3 composite electrode by cathodic deposition for the elimination of phenol by Sonoelectrochemical oxidation

Abstract The preparation of composite metal oxide to attain high efficiency in removing phenol from wastewater has a great concern. In the present study, the focus would be on adopting antimony-tin oxide coating onto graphite substrates instead of titanium; besides the effect of SbCl3 concentration on the SnO2-Sb2O3 composite would be examined. The performance of this composite electrode as the working electrode in the removal of phenol by sonoelectrochemical oxidation will be studied. The antimony-tin dioxide composite electrode was prepared by cathodic deposition with SnCl2 . 2H2O solution in a mixture of HNO3 and NaNO3, with different concentrations of SbCl3. The SnO2-Sb2O3 deposit layer’s structure and morphology were examined and the 4 g/l SbCl3 gave the more crystallized with nanoscale electrodeposition. The highest removal of phenol was 100% at a temperature of 30 oC, with a current density (CD) of 25 mA/cm2.

Study on Improving Efficiency of Perovskite Solar Cells Through Controlling Humidity Conditions and Nickel Oxide Composition

Study on Improving Efficiency of Perovskite Solar Cells Through Controlling Humidity Conditions and Nickel Oxide Composition

Efficient three-dimensional electrochemical degradation of alizarin red by CeO2−MnO2/NF particle electrode synergized with ozone

In this study, nickel foam-loaded Mn and Ce bimetallic oxide composites were successfully synthesized as particle electrodes by a hydrothermal method and synergized with ozone for the efficient degradation of alizarin red (AR), a typical anthraquinone dye. The effects of common factors on the degradation rate of alizarin red were investigated. The optimal experimental conditions were derived as applied voltage = 3.5 V, initial pH = 5.5, NaCl concentration of 4.5 g/L, and initial dye concentration of 20 mg/L. The particle electrode had a high cyclic stability after five cycles. The active sites of the dye molecular structure were analyzed in combination with the Fukui function, and the degradation pathway of alizarin red was proposed on this basis. By comparing the degradation effect of alizarin red under three different systems of O3, 3DER and 3DER-O3, it was confirmed that the three-dimensional electrode has a good synergistic effect in conjunction with ozone. Finally, the degradation mechanism of alizarin red under the CeO2−MnO2/NF synergistic ozone system was derived, in which the single linear oxygen (1O2) played a major role in the degradation process.

Discrimination of VOCs with e-nose consisting of a single MEMS sensor using lightweight deep learning model based on SqueezeNet

The detection of volatile organic compounds (VOCs) has numerous applications in environmental monitoring and biomedicine. Metal oxide semiconductor (MOS) gas sensors are widely used in gas detection due to their simple structure, low fabrication cost, and fast response speed. However, MOS gas sensors have broad-spectrum responsiveness to VOCs, making selectivity a challenge. The most commonly used method to obtain selectivity is the E-nose system consisting of multiple sensors. However, the size of E-noses has increased due to the number of sensors with high power consumption and complicated signal processing. In recent years, deep learning has flourished, allowing for accurate discrimination of VOCs and concentration prediction using E-nose consisting of a single sensor. This method significantly reduces power consumption and facilitates portable applications. In this work, we synthesize SnO2-ZnO composite oxide and fabricate a E-nose consisting of a single MEMS gas sensor. The response performance of the E-nose to VOCs is stable with a high output signal-noise ratio (SNR). We design a lightweight deep learning model based on SqueezeNet and train it using transfer learning. Linear regression is used to predict the concentration of VOCs. Our work achieves accurate identification and low-error concentration prediction of VOCs, which is valuable for subsequent portable VOC detection systems.