ZnFe2O4 ZnO Research Articles

Multi-morphology composite: Particle & petal-shaped ZnFe2O4/flower-shaped ZnO@Porous biomass carbon with excellent broadband microwave absorption performance

Utilizing carbon and magnetic components to construct microwave-absorbing composites with broadband and strong absorption has become a research focus. Improving the structural coupling of these materials to enhance impedance matching and dielectric performance remains a significant obstacle. Particle and petal-shaped ZnFe2O4/flower-shaped ZnO@chestnut shell biomass-carbon composites (ZnFe2O4/ZnO@CBC) were synthesized via a one-step sintering method. The biomass carbon-based material presents a three-dimensional framework structure, while the particle and petal-shaped ZnFe2O4 and flower-shaped ZnO are uniformly distributed on its surface. This distribution significantly improves the dielectric polarization performance and magnetic loss of the material, ultimately leading to good microwave attenuation ability through impedance matching. Taking the addition of 1 g of biomass as an example, the minimum reflection loss (RLmin) of the composite material is −50.43 dB, and the widest effective absorption bandwidth (EAB) reaches 7.13 GHz (10.87–18 GHz). Notably, the EAB of the different composite materials all remains above 6.4 GHz when the biomass addition is adjusted within the range of 1–2.5 g, indicating that they are not sensitive to the amount of biomass used and have good stability in microwave absorption performance. Moreover, the results of the simulation and modeling analyses of the radar cross section (RCS) further validate the efficacy of composite materials in attenuating microwaves. These results offer valuable insights into the stability of bandwidth in materials and the potential application of biomass in wave-absorbing materials. It also shows that the composites are highly promising and reliable candidates for microwave absorption applications due to their high-performance, wide-band, and thin-absorption properties.

ZnO-ZnFe2O4 Catalyst for Hydrogen Production from Methanol Steam Reforming

In this study, ZnFe2O4 and ZnO-ZnFe2O4 catalysts were prepared using the glycine–nitrate process (GNP). The prepared ZnFe2O4 and ZnO-ZnFe2O4 catalyst powders were characterized using a scanning electron microscope, transmission electron microscope, XRD diffraction studies, and selected area diffraction pattern studies. In addition, the specific surface area was measured using a Brunauer–Emmett–Teller specific surface area analysis. The hydrogen reduction in different temperature ranges was analyzed using the H2 temperature-programmed reduction technique. The specific surface area of the ZnFe2O4 was 5.66 m2/g, and the specific surface area of the ZnO-ZnFe2O4 was 8.20 m2/g at a G/N ratio of 1.5 and at a G/N ratio of 1.7, respectively. The specific surface area of the ZnFe2O4 was 6.03 m2/g, and the specific surface area of the ZnO-ZnFe2O4 was 11.67 m2/g. The ZnFe2O4 and ZnO-ZnFe2O4 were found to have the best catalytic effect at 500 °C. In particular, the highest H2 generation rate of the ZnO-ZnFe2O4 (GN = 1.7) at 500 °C was 7745 mL STP min−1 g-cat−1. Moreover, the ZnO-ZnFe2 O4 catalyst demonstrated good H2 selectivity and stability during the process of steam reforming methanol. Therefore, the ZnO-ZnFe2O4 catalyst powder exhibited high catalytic activity due to the good dispersibility of the ZnO, which increased the specific surface area of the catalyst. In the future, the catalyst can be applied to the steam reforming of methanol for industrial purposes.

Concurrent fabrication of ZnO–ZnFe2O4 hybrid nanocomposite for enhancing photocatalytic degradation of organic pollutants and its bacterial inactivation

In this research, we looked at how heterostructure fabrication, phase ratio, and crystalline nature affect the photocatalytic activity of ZnO/ZnFe2O4 nanocomposite for the degradation of Rhodamine B (RhB) dye when exposed to sunlight irradiation. Magnetic ZnO/ZnFe2O4 hybrid nanocomposites were made using a co-precipitation technique. The synthesized hybrid nanocomposite were analyzed using a variety of characterization techniques to understand more about their chemical, crystallinity, and photoactive characteristics. Using UV–Visible spectra, the absorption and photocatalytic efficiency of photocatalysts were investigated. By using XPS and FTIR measurements, the surface composition and functionalization of the produced nanocomposite were observed. The synthesized ZnO/ZnFe2O4 nanocomposites exhibit irregular morphologies, and the average crystallite size is about 30 nm, by the findings of the transmission electron microscope. When exposed to solar light for 90 min, the prepared photocatalysts exceed ZnO nanoparticles in terms of photocatalytic performance by more than 45%. Pseudo-first-order kinetics governs the adsorption of RhB onto nanocomposite surfaces. Finally, the ZnO/ZnFe2O4 nanocomposites were employed for antibacterial treatments against the waterborne pathogens Escherichia coli (E.coli) and Staphylococcus aureus (S.aureus). The outcomes demonstrated that the optimal disinfection efficiency against E. coli and S. aureus germs were 98.6 and 97.4%, respectively, associated with superior cycling durability. Therefore, this work offers a simple and rapid approach to the development of hybrid nanocomposites that could be used to create various photocatalytic and optical materials.

ZnO–ZnFe2O4/Fe3O4/Carbon Nanocomposites for Ultrasensitive and Selective Dopamine Detection

Electrochemical detection of submicromolar levels of dopamine (DA) by iron–carbon-based redox mediators requires the synergistic effect of facile Fe2+ ↔ Fe3+ redox chemistry, high DA adsorption capacity, and fast electron-transfer kinetics. Its absence in most reported mediators has led to detection limits that are well above the lower threshold [DA] in healthy humans (i.e., 0.01 μM). Herein, we report a ZnO–ZnFe2O4/Fe3O4/carbon nanocomposite, which possesses the aforementioned synergy and therefore displays impressive sensing capabilities. ZnO–ZnFe2O4/Fe3O4/carbon is synthesized in situ via the carbothermal reduction of Congo red (CR)-decorated ZnO–ZnFe2O4 nanofibers. This synthesis approach allows CR-derived CO(g) to consume the lattice oxygen at the edges of ZnFe2O4 and generate oxygen vacancy (OV)-rich-Fe3O4/ZnO interfaces embedded in mesoporous graphitic carbon. Differences in work function cause interfacial electron transfer from Fe3O4 to ZnO, which improves the Fe2+ ↔ Fe3+ redox chemistry and increases the charge-carrier concentration and electron-transfer rate. Meanwhile, the lattice vacancies and surface polarization increase the surface energy, which improves DA adsorption. Benefiting from these physicochemical advantages, a nafion/ZnO–ZnFe2O4/Fe3O4/carbon-modified glassy carbon electrode (GCE) displays a low detection limit of 1.57 nM, a high sensitivity of 2.7186 AM–1 cm–2, and a rapid response time of 13 s. Crucially, it selectively detects DA in the presence of 100 times more ascorbic acid, uric acid, urea, and potassium chloride and similar levels of serotonin. In addition, it is stable, reproducible, and active in biological fluids. These properties put nafion/ZnO–ZnFe2O4/Fe3O4/carbon/GCE on the same pedestal as the current state-of-the-art and could therefore potentially be used for the practical diagnosis of DA-related diseases in biomedical applications. Therefore, our results demonstrate that the in situ carbothermic synthesis of Fe3O4 from organic-dye-decorated zinc ferrite nanofiber is a useful method for improving its electrocatalytic properties. This knowledge could potentially be applied to the synthesis of an electrocatalyst for other electrochemical applications.

Structure and composition design on ternary CNT@ZnFe2O4@ZnO composite utilized as enhanced microwave absorbing materials

As the increasing requirements on microwave absorber resulting from the complex application environment, composites consisting of multiple components have obvious superiority to the pure materials. In order to achieve excellent absorption performance for composites, both composition and microstructure should be properly designed. In this work, a three-phase composite consisting of conductive CNT, magnetic ZnFe2O4 and dielectric ZnO with coating structure is designed to enhance the microwave absorbing performance. The three-phase CNT@ZnFe2O4@ZnO composites are prepared by a two-step coprecipitation method. The as-prepared composite shows good impedance matching and high attenuation. When the content of ZnFe2O4 is 3 mmol, the composite has a reflection loss of −33.5 dB at 4.4 GHz. The huge interfaces area attributed to both the multi-phase component and multi-layer structure helps to improve the interface polarization, dipole polarization, multiple reflection and scattering. Besides, the synergy of the different loss mechanisms coming from the different materials can also effectively promote the absorption.

Bio-hydrothermal synthesis of ZnO–ZnFe2O4 nanoparticles using Psidium guajava leaf extract: Role in waste water remediation and plant immunity

Here in, an environmental friendly and chemical free bio-hydrothermal method was developed to synthesize ZnO–ZnFe2O4 nanoparticles (NPs) using Psidium guajava leaf extract. The prepared NPs effectively mediate water remediation process as well as enhance plant immunity. The phase formation, functionality, chemical composition, morphological feature and surface area of the prepared material was analyzed by XRD, XPS, TEM and BET analytical techniques. The average size of the prepared special shaped NPs was found to be 17.8 nm. The synthesized composite material is used for the removal of highly toxic Congo red (CR) and Methylene blue (MB) dyes from water by batch adsorption method. The adsorption processes follow Pseudo-second order kinetics and Langmuir isotherm models. The maximum adsorption capacity was found to be 120.32 mg/g for CR and 90.35 mg/g for MB at the solution pH = 6 and pH = 8 respectively. Strikingly, the fabricated ZnO–ZnFe2O4 NPs enhance the plant immune response and promote plant growth, potentially by preventing transpirational water loss. Specifically, the protein levels of key immune responsive genes including BAK1, FLS2, PR1, MPK3 and MPK6 were elevated for the plants treated with NPs as compared with the control plants.

Magnetic and optical properties of synthesized ZnO–ZnFe2O4 nanocomposites via calcined Zn–Fe layered double hydroxide

Abstract In this article, Zn–Fe layered double hydroxide (Zn–Fe–CO3–LDH) precursors with 1, 2, 3, and 4 values of Zn2+/Fe3+ molar ratio were prepared by coprecipitation method at pH = 8. ZnO/ZnFe2O4 nanocomposite was obtained as the calcination process of LDH precursors. Herein, we explore a prospective strategy to synthesize the zinc ferrite nanostructure by the calcination of Zn–Fe–CO3–LDH precursors. Powder X-ray diffraction (PXRD) exhibited two phases (ZnO and ZnFe2O4). Hall method has been used to calculate the grain size of ZnFe2O4 and was obtained between 19 nm and 32 nm. Magnetic measurements of the ZnFe2O4 phase after the subtraction of the paramagnetic contribution from the whole hysteresis loop of ZnO/ZnFe2O4 nanocomposite were investigated using VSM. The high coercivity values of ZnFe2O4 nanoparticles (~2600 Oe) and low values of the anisotropy constant (0.0004–0.0796) J/m3 were observed which were useful for high-density storage devices application. The values of the optical band gap of the ZnFe2O4 phase were obtained above the bulk value (2.18–2.33 eV) due to the nanosized ZnFe2O4 nature. The Urbach tail energy of ZnFe2O4 nanoparticles was found between 160.3 and 194.1 meV which indicated high localized defect levels in the forbidden band gap of prepared samples. The refractive index relation with photon energy showed normal dispersion behavior for samples at the range below 1.8 eV and anomalous dispersion behavior at the range above 1.8 eV. The values of normal dispersion parameters were calculated in this work for ZnFe2O4 nanostructure as new results which were candidate material in telecommunication applications. All these parameters, in general, increased with the increasing of the Zn2+/Fe3+ molar ratio.

Coral-like ZnFe2O4–ZnO mesoporous heterojunction architectures: synthesis and enhanced sensing properties for triethylamine

A unique coral-like ZnFe2O4–ZnO heterojunction architecture based sensor has been synthesized and shows excellent sensing performance for TEA with a particularly fast response time of 0.9 s.

Nanoheterostructures of ZnO Nanorods Decorated with ZnFe2O4 Nanoparticles by a Simple Solution Process

Background: Nanoheterostructures of ZnFe2O4–ZnO is a potential functional material synthesized by various complicated synthesis processes. However, most of the processes are not at all cost effective because these generally require high-temperature treatment as well as long reaction time and complicated experimental procedure. Thus, a simple, low cost and highly efficient synthesis process is still highly required. Objective: The aim of the present study is to synthesize ZnFe2O4–ZnO nanoheterostructures by a simple solution process vis-à-vis to characterize the structural and optical properties of the sample. Methods: Nanoheterostructures of ZnFe2O4 decorated on ZnO nanorods (ZFZO) have been synthesized by two-step low-temperature solution process in the presence of hydrazine hydrate. Results: X-ray diffraction study showed the presence of hexagonal ZnO and cubic ZnFe2O4 spinel. Transmission electron microscopic analysis confirmed the formation of nanoheterostructures of ZnFe2O4 decorated on ZnO nanorods. The optical property of the sample was characterized by UVVisible spectroscopy. Moreover, the oxidation states of the elements were examined by X-ray photoelectron spectral studies. A probable formation mechanism of the nanoheterostructures was drawn. Conclusion: This simple solution based synthesis process is found to be an easy and cost- effective synthesis strategy as realized from the characterizations of structural and functional properties of the synthesized samples of ZnFe2O4–ZnO nanoheterostructures.

A stable novel nanostructure of ZnFe2O4 based nanocomposite for improved photoelectrocatalytic and photocatalytic activities

A nonagon ZnO–ZnFe2O4 nanocomposite was synthesized using high-energy ball milling followed by post-annealing with an initial mixture of high purity magnetite (Fe3O4) and zincite (ZnO) powders. The effects of the process parameters on the structural, optical, photocatalytic, and photoelectrocatalytic activities were investigated. X-ray diffraction analysis was used to confirm the presence cubic spinel ZnFe2O4 and hexagonal ZnO crystal phases. The lowest optical bandgap observed was 1.83 eV, which decreased due to post-annealing. The photocatalytic activity of the 800 °C post-annealed nanocomposite exhibited the highest degradation percentage of 96% over 180 min under visible light, with a degradation rate constant of 1.5 min−1. Furthermore, the optimized sample showed no substantial decrease in photocatalytic activity after five cycles of the repeated catalysis experiment. In electrochemical studies, when compared to the other post-annealed samples, the 800 °C post-annealed nanocomposite showed the highest water splitting activity with the lowest charge-transfer resistance of 75 Ω, photocurrent density of 4.3 × 10−5 Acm−2, exchange current density of 4.19 log JA−1 cm−2, and Tafel slopes of 74.1 mVdec−1. In dual activities, the performance of the 800 °C post-annealed nanocomposite was noticed to be enhanced. This nanocomposite has potential industrial applications as a cost-effective catalyst.

Electrospun ZnFe2O4-based nanofiber composites with enhanced supercapacitive properties

Herein, we are reporting a facile method to synthesis ZnFe2O4-based nanofibers (ZnFe2O4, ZnO–ZnFe2O4 and Fe2O3–ZnFe2O4) via the electrospinning technique using zinc acetonate and ferric acetonate as the metal oxide precursor and polyvinyl pyrrolidone (PVP) as the polymer. The as-prepared electrospun nanofiber composites were calcined at 500°C to obtain crystalline porous nanofibers. The effect of different compositions on the morphology of each sample as well as their electrochemical properties when employed as electrode materials was studied. The results show that the as-prepared electrodes exhibited excellent performance with their specific capacitances calculated from the CV curves as 590, 490 and 450Fg−1 for Fe2O3–ZnFe2O4, ZnO–ZnFe2O4 and ZnFe2O4 respectively at a scan rate of 5mVs−1. Excellent stability of the electrodes was also observed even after 3000 cycles. The results obtained suggest these electrode materials might be promising candidates for supercapacitor application.

Visible light photocatalytic activities of ZnFe2O4/ZnO nanoparticles for the degradation of organic pollutants

ZnFe2O4/ZnO nanoparticles have been synthesized by co-precipitation method using polyvinyl alcohol (PVA) as surfactant. The phase formation of synthesized products was systematically investigated from powder X-ray diffraction. Cubic ZnFe2O4 and hexagonal ZnO were identified in accordance with different molar concentrations of Fe3+ ions. The morphology and functionality were analyzed using field emission scanning electron microscopy (FESEM), transmission electron microscopy (TEM) and Fourier transform infrared (FTIR) spectroscopy. The optical properties and change in the band gap from UV to visible region upon increasing molar concentration of Fe3+ ions were analyzed from diffuse reflectance spectra (DRS). Superparamagnetic property was observed for synthesized ZnFe2O4/ZnO nanoparticles using vibrating sample magnetometer (VSM). The methylene blue and methyl orange were taken as model dyes to illustrate the photocatalytic activity of synthesized products under visible light irradiation. Maximum degradation of 99% for methyl orange (MO) was achieved by the use of 13 nm sized ZnFe2O4/ZnO nanoparticles as catalyst and a minutely less activity was observed for the methylene blue (MB) degradation (98%), when the photocatalytic processes were carried out for 5 h and 6 h, respectively.

Physical synthesis methodology and enhanced gas sensing and photoelectrochemical performance of 1D serrated zinc oxide-zinc ferrite nanocomposites.

sWe successfully prepared one-dimensional ZnO–ZnFe2O4 (ZFO) heterostructures for acetone gas-sensing and photoelectrochemical applications, by using sputter deposition of ZFO crystallites on ZnO nanostructure templates. The nanoscale ZFO crystallites were homogeneously coated on the surfaces of the ZnO nanostructures. Electron microscope images revealed that the ZnO–ZFO heterostructures exhibited a serrated surface morphology. Coating the ZnO nanostructures with a ZFO aggregated layer appreciably enhanced their acetone gas-sensing capability at 250 °C in comparison with pure ZnO nanostructures. The presence of many depleted nanoscale ZFO crystallites, the rugged surface of the heterostructures, and electron depletion at the ZnO/ZFO interface might contribute to the enhanced acetone gas-sensing response. Furthermore, the larger surface area and higher light absorption of ZnO–ZFO relative to the surface area and light absorption of ZnO were correlated with a substantial enhancement of the photocurrent value of ZnO–ZFO in photoelectrochemical tests produced by the simulated solar light irradiation.

Selective formation of light olefins from CO2 hydrogenation over Fe–Zn–K catalysts

Fe–Zn–K catalysts were prepared in varied Fe/Zn molar ratios using microwave-aided hydrothermal procedure followed by K modification with impregnation method and applied to CO2 hydrogenation reaction via Fischer–Tropsch synthesis for the selective production of C2–C4 olefins. Results showed that the prepared catalysts had uniform particles within about 100nm. Addition of zinc to iron matrix formed ZnFe2O4 spinel phase and ZnO phase, and caused increase of the surface areas, enhanced the interaction between iron and zinc and altered the reduction and CO2 adsorption behaviors. The catalysts displayed high activity for the CO2 conversion and significant improvement in the product distribution. The proper interactions between Fe and Zn proved to be advantageous to suppress the production of C5+ hydrocarbons and promote the production of C2–C4 olefin. At set reaction conditions of H2/CO2 of 3, GHSV of 1000h−1, 320°C, and 0.5MPa, the 1Fe–1Zn–K catalyst with H2/CO reduction showed the best performance with the CO2 conversion of 51.03%. The selectivity of C2–C4 olefins in overall hydrocarbons and the ratio of olefin to paraffin in the C2–C4 fraction reached 53.58% and 6.86, respectively.

Preparation and photocatalytic application of Zn[sbnd]Fe2O4@ZnO core–shell nanostructures

In this study, nanohallow ZnFe2O4 microspheres were synthesis by ZnCl2, FeCl3⋅6H2O and ammonium acetate using the hydrothermal method. Then, ZnFe2O4@ZnO core–shell structured spheres were prepared by using immobilization of ZnO nanoparticles on the surface of Zn-ferrite spheres via sol–gel rout. SEM and TEM images showed morphology and core–shell structure of particles. Results of VSM illustrate that ZnFe2O4 and ZnFe2O4@ZnO particles are superparamagnetic. Photocatalytic activity studies confirm that synthesised ZnFe2O4@ZnO core–shell sphere with molar ratio of 1:1 had excellent photodegradating behavior to methylene blue (MB) as compared to other core–shell ratios, pure ZnFe2O4 and pure ZnO.

Synthesis and gas sensor application of ZnFe2O4–ZnO composite hollow microspheres

In this contribution, ZnFe2O4–ZnO composite hollow microspheres were successfully synthesized by a glucose-assisted hydrothermal method only using Fe(NO3)3·9H2O, Zn(NO3)2·6H2O and glucose as starting materials, followed by a calcination treatment. The characterization results from scanning electron microscopy (SEM), transmission electron microscopy (TEM), X-ray powder diffraction (XRD) and X-ray photoelectron spectroscopy (XPS) revealed that the as-synthesized ZnFe2O4–ZnO composite hollow microspheres, with a diameter range of 1 to 2.5 μm and a shell thickness of about 60 nm, consist of numerous small cubic spinel ZnFe2O4 nanoparticles and hexagonal wurtzite ZnO nanoparticles. In order to investigate the potential applications, the resulting ZnFe2O4–ZnO composite hollow microspheres were employed to fabricate a gas sensor using four common volatile organic pollutants (VOPs) namely n-butanol, acetone, ethanol and methanol as probe gases. The gas sensing measurement results demonstrated that the sensor based on the as-obtained ZnFe2O4–ZnO composite hollow microspheres exhibited a high response, good reversibility and reproducibility, and quick response and recovery characteristics. The composite sensor also showed enhanced responses compared with the pure ZnO sensor, which could be contributed to the unique rough, porous and hollow structure of the ZnFe2O4–ZnO composite hollow microspheres, and the heterojunction action at the interfaces of ZnFe2O4–ZnO. It is expected that the current ZnFe2O4–ZnO composite hollow microspheres have promising applications in gas sensors and can be further applied in other fields such as photocatalysis and magnetic resonance imaging.

A nanostructured ZnO–ZnFe2O4 heterojunction for the visible light photoelectrochemical oxidation of water

A heterojunction is successfully fabricated by decorating ZnO nanorods with water-soluble, mono-dispersed ZnFe2O4 particles. In comparison with bare ZnO, the enhanced visible light absorption and photocurrent (λ > 420 nm) for the photoanode of the ZnO–ZnFe2O4 composite is correlated with the visible light response of the ZnFe2O4 prepared and the rapid charge transfer within the heterojunction as evidenced by the electrochemical impedance spectra.

A ZnFe2O4–ZnO nanorod array p–n junction composite and its photoelectrochemical performance

A ZnFe2O4-ZnO nanorod array (NRA) with a three-dimensional network nanometer structure was prepared. The photoelectrochemical performance of the ZnFe2O4-ZnO NRA composite is significantly improved due to the formation of a p-n heterojunction electric field at the interface between ZnFe2O4 and ZnO, the increase of the overall utilization efficiency of incident light energy, and the visible light absorption capability of ZnFe2O4.

Chlorination and evaporation behaviours of zinc and lead at chlorinating and oxidising atmosphere

Treatment of electric arc furnace (EAF) dust has become an important issue from the viewpoint of environmental protection and recycling of valuable resources because EAF dust contains considerable amount of zinc and lead. A new recovery process of these metals has been proposed, in which the metals in the dust react with waste polyvinyl chloride, and the produced metal chlorides are removed as gaseous species from the oxide residue. Therefore, it is important to clarify the chlorination and evaporation behaviours of zinc and lead in the chlorinating and oxidising atmosphere. In the present study, the kinetics of chlorination of ZnO, PbO and ZnFe2O4, which are the main constituents containing Zn and Pb in the EAF dust, were measured from 1023 to 1373 K with Ar–O2–Cl2 atmosphere. Based on these results, the selective chlorination and evaporation process of zinc and lead from the mixture of Fe2O3–ZnFe2O4–ZnO–PbO was examined at 1073 K with Ar–Cl2–O2 atmosphere, and the high efficiency of selectivity was demonstrated.

Solvent thermal synthesis and gas-sensing properties of Fe-doped ZnO

In this study, pure ZnO microbullets, ZnO–ZnFe2O4 composite, and ZnO–Fe2O3–ZnFe2O4 composite with micron structured balloons, rods, and particles were prepared by a simple solvent thermal process using methanol or ethanol as solvents. The influence of solvents on the composition and morphology of the products was studied, and their gas-sensing properties were also investigated. The morphology of ZnO microbullets synthesized in ethanol is similar to but more uniform than that of ZnO microbullets synthesized in methanol. The Fe-doped ZnO synthesized in ethanol contains many micron particles homogeneously dispersing on the surface of the microbullets, which is composed of hexagonal wurtzite ZnO and franklinite ZnFe2O4, while Fe-doped ZnO prepared in methanol consists of micron structured balloons, rods, and particles, which is composed of hexagonal wurtzite ZnO, hematite Fe2O3, and franklinite ZnFe2O4. Compared with pure ZnO and ZnO–ZnFe2O4 composite, the ZnO–Fe2O3–ZnFe2O4 composite presented high response, rapid response/recovery characteristics, good selectivity, and excellent stability to acetone at relatively low operating temperature of 190 °C. This sensor could detect acetone in wide range of 1–1000 ppm, which was expected to be a promising gas sensor for detecting acetone.