Synthesis and Characterization of Corncob-Derived Mn-Doped Fe₃O₄/rGO Nanocomposites with Soft Magnetic Behavior for Potential Electromagnetic and Engineering ApplicationsAbstract
Mn-doped Fe3O4/reduced graphene oxide (rGO) nanocomposites derived from corncob biomass were successfully synthesized as sustainable magnetic nanomaterials for engineering applications. Biomass-derived rGO was prepared from corncob waste, while Mn-doped Fe3O4 nanoparticles were synthesized using a coprecipitation method and subsequently integrated with the rGO matrix. The structural, morphological, chemical, and magnetic properties of the synthesized nanocomposites were characterized using X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), scanning electron microscopy coupled with energy-dispersive X-ray spectroscopy (SEM–EDS), and vibrating sample magnetometry (VSM). XRD analysis confirmed the formation of a single-phase cubic spinel Fe3O4 structure with an average crystallite size of 11.5 nm and no detectable secondary phases. SEM observations revealed agglomerated ferrite particles uniformly distributed on layered rGO sheets, while EDS confirmed the presence of Fe, Mn, C, and O within the composite. The complementary results obtained from XRD, FTIR, SEM–EDS, and VSM collectively confirmed the successful formation of the Mn-doped Fe3O4/rGO nanocomposite. The synthesized material exhibited soft magnetic behavior with a saturation magnetization (Ms) of 32.83 emu g−1. The narrow hysteresis loop and magnetic response are consistent with the characteristics commonly observed in nanoscale ferrite nanocomposites, demonstrating its potential for electromagnetic interference shielding, magnetic separation, sensing technologies, and other sustainable magnetic engineering applications.
Keywords:
Mn-doped Fe3O4; rGO; corncob biomass; nanocomposite; coprecipitation
1. Introduction
Nanocomposite materials have attracted significant attention due to their unique structural, electrical, and magnetic properties compared to conventional materials. By combining different nanoscale components, synergistic effects can be achieved, leading to enhanced functional performance for various technological applications such as sensors, catalysis, environmental remediation, and energy storage systems1,2. In recent years, the development of multifunctional nanocomposites has become increasingly important in engineering fields that require materials with combined magnetic responsiveness, structural stability, and high surface area.
Among magnetic nanomaterials, magnetite (Fe3O4) nanoparticles are widely investigated for their strong magnetic properties, chemical stability, and relatively simple synthesis methods. These characteristics make Fe3O4 promising for engineering applications, including magnetic separation systems, electromagnetic interference (EMI) shielding, and magnetic sensing devices. However, pure Fe3O4 nanoparticles tend to agglomerate and exhibit limited electrical conductivity, which may reduce their performance in advanced functional applications3. To overcome these limitations, Fe3O4 nanoparticles are often combined with conductive carbon materials such as graphene or reduced graphene oxide (rGO), which provide high surface area, excellent electrical conductivity, and good mechanical stability4,5.
Spinel ferrite nanomaterials (MFe2O4, where M = Mn, Co, Ni, Zn, or other divalent metal ions) have attracted considerable attention owing to their tunable magnetic, electrical, and structural properties. These materials exhibit excellent chemical stability, high magnetic responsiveness, and versatile functionality, making them promising candidates for applications in electromagnetic interference shielding, sensing devices, catalysis, environmental remediation, and energy-storage systems6,7. The properties of spinel ferrites can be effectively tailored through cation substitution, which modifies the distribution of metal ions within the tetrahedral and octahedral sites of the spinel lattice. Such modifications influence crystallite size, magnetic exchange interactions, electrical conductivity, and overall material performance. Recent studies have demonstrated that controlled doping of ferrite nanomaterials provides an effective strategy for enhancing their functional properties and expanding their applicability in advanced engineering and technological fields7.
In addition to structural modification using carbon materials, the physical and magnetic properties of Fe3O4 can be improved through transition-metal doping. Manganese (Mn) is one of the most commonly used dopant elements because Mn ions can substitute Fe ions within the spinel lattice structure, thereby modifying the cation distribution and magnetic interactions of the material8-10. Previous studies have shown that Mn doping can significantly influence crystallite size, magnetic properties, and electronic interactions in ferrite nanomaterials11, which are critical parameters in determining the performance of magnetic nanomaterials in real engineering environments.
Recently, biomass-derived carbon materials have attracted increasing interest as sustainable alternatives for advanced nanomaterial synthesis. Agricultural waste, such as corncob, is abundant, inexpensive, and rich in carbon, making it a promising precursor for producing graphene-based carbon materials11-13. The conversion of biomass into functional carbon materials not only provides renewable resources for nanomaterial synthesis but also contributes to waste valorization and environmentally friendly material development, which aligns with the growing demand for sustainable engineering materials.
Recent advances in ferrite/reduced graphene oxide (rGO) nanocomposites have demonstrated their potential for a wide range of engineering applications, including electromagnetic interference (EMI) shielding, energy storage, environmental remediation, and sensing technologies. The incorporation of rGO into ferrite systems has been reported to enhance electrical conductivity, interfacial polarization, and charge-transfer efficiency, resulting in improved functional performance compared with pristine ferrites14,15. Furthermore, Mn-containing ferrites and ferrite/rGO hybrid nanocomposites have shown tunable magnetic, dielectric, and electrochemical properties through compositional engineering and cation substitution15,16. Several recent studies have successfully developed ferrite/rGO-based nanocomposites with enhanced microwave absorption, electrochemical activity, and magnetic responsiveness. However, most of these studies rely on commercially available graphene derivatives or synthetic carbon precursors, while investigations utilizing biomass-derived rGO as a sustainable carbon source remain relatively limited14,15. This limitation highlights the need for environmentally friendly approaches for producing ferrite/rGO nanocomposites with tailored magnetic and structural properties.
Although ferrite/rGO nanocomposites and Mn-substituted ferrites have been extensively investigated because of their attractive magnetic and electrical properties, most reported studies utilize commercially available graphene oxide, graphite derivatives, or synthetic carbon precursors. Furthermore, previous studies have primarily focused on improving magnetic, electrochemical, or dielectric performance, whereas the utilization of renewable biomass resources as carbon precursors has received comparatively less attention14,15. In particular, the combined influence of Mn incorporation and biomass-derived rGO on the structural evolution, crystallite characteristics, and magnetic behavior of Fe3O4-based nanocomposites has not been systematically investigated. Therefore, further research is required to develop sustainable ferrite/rGO nanocomposites that integrate waste-derived carbon materials with magnetic-property engineering through controlled cation substitution.
Unlike previously reported ferrite/rGO nanocomposites that rely on commercial graphene-based materials, the present study combines corncob biomass-derived rGO with Mn-doped Fe3O4 nanoparticles synthesized from natural iron sand, providing a sustainable route for producing functional magnetic nanocomposites with tailored structural and magnetic properties. Therefore, this study aims to synthesize Mn-doped Fe3O4/rGO nanocomposites using corncob biomass as a renewable carbon source and natural iron sand as the iron precursor.
The development of biomass-derived magnetic nanocomposites is expected to contribute to sustainable materials engineering by simultaneously addressing agricultural waste utilization and the growing demand for advanced functional magnetic materials for engineering applications. In this study, Mn-doped Fe3O4/rGO nanocomposites derived from corncob biomass were successfully synthesized using the coprecipitation method17. The structural, morphological, and magnetic properties of the synthesized materials were systematically investigated using X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), scanning electron microscopy with energy dispersive spectroscopy (SEM-EDS), and vibrating sample magnetometry (VSM)9,18. The findings of this work are expected to contribute to the development of sustainable magnetic nanocomposites with potential applications in magnetic separation systems, electromagnetic shielding materials, and advanced sensing technologies.
2. Materials and Methods
2.1. Materials
The materials used in this study included natural iron sand, a manganese precursor, and corncob biomass as the carbon source for reduced graphene oxide (rGO). Natural iron sand was collected from Sine Beach, Tulungagung, Indonesia, and used as the primary source of iron oxide. Corncob biomass was used as the raw material for producing carbon-based materials due to its high carbon content and availability as agricultural waste19,20. Hydrochloric acid (HCl) was used to dissolve iron components from the iron sand, while other supporting chemicals were used during the synthesis and preparation process. Table 1 shows the materials used in this research.
2.2. Preparation of reduced graphene oxide from corncob biomass
Corncob biomass was first washed with distilled water to remove surface impurities and then dried in an oven at 100 °C for 24 h. The dried biomass was subsequently subjected to an initial combustion process to obtain carbonized material. The resulting char was ground using a mortar and pestle and sieved to obtain fine carbon powder21.
The obtained powder was further carbonized in a furnace at 400 °C for 3 h under limited oxygen conditions. During the thermal carbonization process, the decomposition of lignocellulosic components such as cellulose, hemicellulose, and lignin led to the formation of carbon-rich structures. This thermal decomposition promotes the rearrangement of carbon atoms and the development of partially ordered sp2 graphitic domains, which are commonly associated with graphene-like carbon materials derived from biomass21.
After the carbonization process, 5 g of the carbon powder was dispersed in 50 mL of distilled water and ultrasonicated for 2 h to facilitate the exfoliation of carbon layers and improve the dispersion of the carbon sheets. The suspension was then centrifuged at 6000 rpm for 20 min to separate the finer carbon fraction from larger particles. The collected precipitate was filtered and dried in an oven at 100 °C to obtain biomass-derived reduced graphene oxide-like carbon (rGO-like) from corncob biomass.
2.3. Preparation of Mn-Doped Fe3O4 precursors from iron sand
Iron sand collected from Sine Beach was first washed with distilled water to remove surface impurities and then dried in an oven at 100 °C for 12 h. The dried iron sand was subsequently separated using a permanent magnet to isolate the magnetic fraction from non-magnetic impurities19. The magnetic fraction was then dissolved in 2 M hydrochloric acid (HCl) under continuous stirring at 70 °C for 1 h to produce an iron chloride precursor solution. After the dissolution process, the solution was filtered to remove insoluble impurities and residual sand particles.
To introduce manganese doping, manganese chloride hexahydrate (MnCl2·6H2O) was added to the iron precursor solution according to the required molar ratio corresponding to the general formula MnxFe3−xO4. The amount of MnCl2·6H2O was calculated based on the desired Mn/Fe molar ratio for each composition. In this study, the Mn doping composition (x) was varied at 0, 0.2, 0.4, 0.6, 0.8 and 1.0 to investigate the effect of manganese incorporation on the structural and electrical properties of the synthesized materials20,22. Subsequently, 10 mL of diethylamine dissolved in 15 mL of distilled water was added dropwise into the mixed metal precursor solution under continuous stirring. The mixture was further stirred for 60 min at room temperature to ensure complete mixing and to obtain a homogeneous precursor solution before the subsequent nanocomposite synthesis process.
2.4. Synthesis of Mn-Doped Fe3O4/rGO nanocomposite
The coprecipitation method was selected for the synthesis of Mn-doped Fe3O4/rGO nanocomposites because it offers several advantages over alternative techniques such as sol–gel, hydrothermal, solvothermal, and combustion methods. Coprecipitation is a simple, cost-effective, and scalable synthesis approach that can be performed under relatively mild reaction conditions without requiring sophisticated equipment or high processing temperatures23. In addition, the method provides good control over chemical composition, promotes homogeneous nucleation of ferrite nanoparticles, and enables efficient incorporation of dopant ions into the spinel structure22. The low-temperature synthesis process also facilitates the preservation of the structural integrity of rGO sheets and supports the uniform deposition of magnetic nanoparticles on the carbon matrix. These advantages make coprecipitation particularly promising for the large-scale production of ferrite-based magnetic nanocomposites23.
2.5. Characterization techniques
The synthesized Mn-doped Fe3O4/rGO nanocomposite was characterized using several analytical techniques to evaluate its structural, morphological, chemical, and magnetic properties. X-ray Diffraction (XRD) analysis was performed using Cu–Kα radiation (λ = 1.5406 Å) to determine the crystal structure, crystallite size, and phase composition of the synthesized nanocomposite. The diffraction patterns were recorded in the 2θ range of 20°–80° with a step size promising for phase identification24.
Fourier Transform Infrared Spectroscopy (FTIR) was used to identify the functional groups and chemical bonding present in the nanocomposite. The FTIR spectra were recorded in the wavenumber range of 400–4000 cm−1.
Scanning Electron Microscopy coupled with Energy Dispersive X-ray Spectroscopy (SEM–EDS) was employed to investigate the surface morphology, particle size distribution, and elemental composition of the synthesized material. The SEM analysis was conducted at an accelerating voltage of 15 kV.
Vibrating Sample Magnetometer (VSM) measurements were carried out to evaluate the magnetic properties of the nanocomposite, including saturation magnetization, coercivity, and magnetic behavior. The magnetic measurements were performed at room temperature under an applied magnetic field ranging from −15 kOe to +15 kOe.
2.6. Experimental flow diagram
The overall experimental procedure for synthesizing the Mn-doped Fe3O4/rGO nanocomposite derived from corncob biomass is summarized in Figure 1. The synthesis process consisted of four main stages: preparation of rGO from corncob biomass, extraction of iron precursor from iron sand, Mn doping process, and nanocomposite formation using the coprecipitation method.
Experimental flow diagram of Mn-doped Fe3O4/rGO nanocomposite synthesis. Source: Authors (2026).
Initially, corncob biomass was cleaned, dried, and carbonized at 400°C for 3 hours to obtain carbon powder. The carbonized material was then dispersed in distilled water and subjected to ultrasonic treatment to form reduced graphene oxide (rGO). The resulting suspension was centrifuged, filtered, and dried to obtain rGO powder22,25.
In the second stage, iron sand collected from Sine Beach was separated using a permanent magnet to obtain the magnetic fraction. The magnetic material was then dissolved in hydrochloric acid (HCl) to produce an iron chloride precursor solution. The solution was filtered to remove impurities before the addition of the manganese precursor. Next, manganese chloride (MnCl2·6H2O) was introduced into the iron precursor solution to form Mn-doped iron oxide with the general composition MnxFe3−xO4. The mixture was stirred to ensure homogeneous distribution of Mn ions within the iron oxide structure.
Finally, the Mn-doped Fe3O4 precursor solution was combined with rGO powder and subjected to the coprecipitation process by gradually adding NH4OH until precipitation occurred at approximately neutral pH. The formed black precipitate was separated magnetically, washed with distilled water and ethanol, and dried at 100°C to obtain the Mn-doped Fe3O4/rGO nanocomposite. The complete synthesis route is illustrated in the experimental flow diagram shown in Figure 1.
3. Results and Discussions
3.1. XRD analysis
The XRD patterns presented in Figure 2 exhibit characteristic diffraction peaks at 2θ ≈ 30.1°, 35.5°, 43.2°, 53.5°, 57.1°, and 62.7°, which are indexed to the (220), (311), (400), (422), (511), and (440) planes of the cubic spinel Fe3O4 structure. These diffraction peaks are in good agreement with standard JCPDS data, confirming the successful formation of a crystalline magnetite phase within the nanocomposite20,21.
XRD Diffraction Patterns of (a) Corncob-Derived rGO and (b) Mn-Doped Fe3O4/rGO. Source: Authors (2026).
Notably, no secondary phases related to manganese oxides are observed, indicating that Mn ions are effectively incorporated into the Fe3O4 lattice rather than forming separate impurity phases. In addition, a slight broadening and subtle shift of diffraction peaks can be observed, which may be attributed to lattice distortion induced by Mn2+ substitution. Considering that the ionic radius of Mn2+ (0.83 Å) is larger than that of Fe3+ (0.65 Å), the substitution is expected to induce lattice expansion and local structural strain, which in turn affects crystallite growth and structural ordering.
The average crystallite size, estimated using the Scherrer equation26, is approximately 11.5 nm, indicating the formation of nanoscale crystallites. The relatively small crystallite size suggests that the coprecipitation process favors nucleation over crystal growth. Furthermore, the presence of rGO sheets plays a significant role in restricting crystallite growth by acting as a physical barrier, thereby reducing particle agglomeration and promoting uniform dispersion of nanoparticles.
Compared with previously reported Fe3O4/rGO nanocomposites, which typically exhibit crystallite sizes of 10–30 nm 19,20, the smaller crystallite size obtained in this study indicates improved control over nucleation and growth mechanisms. This behavior can be associated with the synergistic effect of Mn doping and rGO incorporation, where Mn-induced lattice distortion suppresses crystal growth while rGO provides heterogeneous nucleation sites. Consequently, the combined effect contributes to enhanced structural stability and potentially influences the magnetic behavior of the nanocomposite.
The formation of well-defined Fe3O4 crystalline phases suggests that the composite exhibits stable magnetic properties. Such stability is beneficial for applications involving magnetic-field interactions, including electromagnetic-wave absorption and magnetic-sensing devices.
3.2. Morphology analysis (SEM)
The SEM micrographs presented in Figures 3a and 3b illustrate the surface morphology of the synthesized Mn-doped Fe3O4/rGO nanocomposite at two different magnifications. The low-magnification image (10 μm scale bar) reveals agglomerated particle clusters uniformly distributed throughout the carbonaceous matrix, whereas the higher-magnification image (500 nm scale bar) shows finer agglomerates associated with layered carbon structures. Such agglomeration is characteristic of ferrite-based nanocomposites and is mainly attributed to magnetic dipole–dipole interactions together with the high surface energy of Fe3O4 nanoparticles, which promote particle clustering during the synthesis process27-29.
Although individual nanoparticles could not be directly resolved using conventional SEM because of its limited spatial resolution, the overall morphology clearly demonstrates the formation of ferrite-rich agglomerates dispersed on the carbonaceous matrix. The nanoscale nature of the magnetic phase was independently confirmed by XRD analysis, which yielded an average crystallite size of approximately 11.5 nm using the Scherrer equation. Therefore, the SEM observations should be interpreted as representative of secondary particle agglomerates, whereas the crystallite dimensions were determined from XRD characterization24,26,30,31.
The coexistence of ferrite-rich agglomerates and layered carbonaceous regions suggests successful incorporation of Mn-doped Fe3O4 within the biomass-derived rGO matrix. This observation is further supported by the FTIR spectra, which confirm the coexistence of Fe–O and carbon-related functional groups, together with SEM–EDS elemental analysis verifying the presence of Fe, Mn, C, and O in the synthesized composite. Similar morphological characteristics have been reported for Fe3O4/rGO nanocomposites synthesized through coprecipitation and related methods27.
Direct visualization of individual nanoparticles and the interfacial contact between Mn-doped Fe3O4 and rGO would require higher-resolution characterization techniques such as FESEM or TEM. These characterization techniques were not available during the present investigation. Nevertheless, the successful formation of the Mn-doped Fe3O4/rGO nanocomposite was verified through complementary structural, chemical, and magnetic characterization using XRD, FTIR, SEM–EDS, and VSM, which collectively provide consistent evidence for the formation of the nanocomposite32.
3.3. FTIR analysis
The FTIR spectrum shown in Figure 4 confirms the successful formation of the Mn-doped Fe3O4/rGO nanocomposite. The absorption band at 570–590 cm−1 corresponds to Fe–O stretching vibrations, which is a characteristic feature of the magnetite spinel structure33. The broad peak around ~3400 cm−1 is attributed to O–H stretching vibrations from hydroxyl groups and adsorbed water molecules. The peak near ~1600 cm−1 corresponds to C=C stretching, indicating the restoration of the sp2 carbon network in rGO, while bands in the range of 1000–1200 cm−1 are associated with C–O functional groups34.
The coexistence of Fe–O and carbon-related functional groups indicates successful integration between Fe3O4 nanoparticles and rGO sheets. These functional groups play an important role in facilitating interfacial bonding and stabilizing the composite structure23,29. This result is consistent with XRD and SEM analyses, confirming the formation of a hybrid nanocomposite system.
3.4. Magnetic properties (VSM)
The magnetic hysteresis loop shown in Figure 5 is a narrow S-shaped curve with very low coercivity and negligible remanent magnetization, indicating soft-magnetic behavior characteristic of nanoscale ferrite materials. The saturation magnetization (Ms) of the optimized Mn-doped Fe3O4/rGO nanocomposite was measured to be 32.83 emu g−1. Compared with bulk Fe3O4, the lower saturation magnetization can be attributed to the nanoscale crystallite size, the incorporation of non-magnetic rGO, and the modification of magnetic exchange interactions resulting from Mn substitution within the spinel lattice29,35,36.
The magnetic response observed in the optimized sample is consistent with the XRD results, which indicate an average crystallite size of approximately 11.5 nm. At this crystallite size, thermal fluctuations significantly reduce magnetic anisotropy, resulting in a narrow hysteresis loop commonly observed in ferrite nanoparticles. Similar magnetic behavior has been reported for Mn-doped Fe3O4/rGO nanocomposites synthesized by coprecipitation, where reduced crystallite size and homogeneous dispersion on rGO contribute to soft magnetic characteristics29,36,37.
Among the synthesized compositions, the Mn0.2Fe2.8O4/rGO sample exhibited the highest magnetic response during preliminary evaluation and was therefore selected for detailed magnetic characterization using VSM. The magnetic behavior of the remaining compositions is summarized qualitatively in Table 2 to illustrate the overall influence of Mn substitution on the magnetic properties of the synthesized nanocomposites36,38.
Although only the optimized composition was subjected to detailed VSM characterization, the observed magnetic behavior is consistent with the structural evolution revealed by XRD and the compositional analysis obtained from SEM–EDS. Therefore, the complementary characterization results collectively indicate that moderate Mn incorporation improves the magnetic response while maintaining the structural integrity of the Fe3O4/rGO nanocomposite31,37,39. Future work will include comprehensive magnetic characterization of all Mn compositions together with quantitative evaluation of remanent magnetization (Mr), coercivity (Hc), and the Mr/Ms ratio to further verify the magnetic domain behavior of the synthesized nanocomposites. Quantitative evaluation of the Mr/Ms ratio is widely recognized as an important criterion for distinguishing superparamagnetic from ferrimagnetic behavior and will be considered in future investigations39.
3.5. Engineering application perspective
The synthesized Mn-doped Fe3O4/rGO nanocomposite exhibits a synergistic combination of magnetic and conductive properties. The rGO matrix enhances electrical conductivity and structural stability, while Fe3O4 nanoparticles provide magnetic responsiveness.
In electromagnetic interference (EMI) shielding applications, the material can contribute to both dielectric loss (from rGO) and magnetic loss (from Fe3O4), improving electromagnetic wave absorption performance34. The combination of biomass-derived rGO and Mn-doped Fe3O4 provides a sustainable magnetic nanocomposite with promising potential for various engineering applications.
The soft magnetic behavior exhibited by the synthesized material, together with its moderate saturation magnetization, makes it promising for electromagnetic interference (EMI) shielding, magnetic separation, microwave absorbing materials, environmental remediation, and magnetic sensing devices. Furthermore, the incorporation of biomass-derived rGO improves electrical conductivity, chemical stability, and structural integrity, while Mn substitution enhances the magnetic response of the ferrite phase. These combined characteristics demonstrate the feasibility of utilizing agricultural waste-derived carbon materials as environmentally friendly reinforcement for multifunctional magnetic nanocomposites33.
The use of corncob biomass as a carbon source further enhances the material's sustainability, offering a low-cost and environmentally friendly alternative for large-scale production11,13. This combination of functional performance and sustainability makes the nanocomposite a promising candidate for advanced engineering applications.
4. Conclusions
Mn-doped Fe3O4/rGO nanocomposites were successfully synthesized through a coprecipitation approach using corncob biomass-derived rGO and natural iron sand as sustainable precursor materials. XRD analysis confirmed the formation of a single-phase cubic spinel Fe3O4 structure with an average crystallite size of approximately 11.5 nm, while SEM observations revealed agglomerated ferrite particles uniformly distributed on the layered rGO matrix. FTIR and SEM–EDS analyses further verified the successful incorporation of Mn-doped Fe3O4 within the biomass-derived rGO matrix. Magnetic characterization demonstrated a saturation magnetization (Ms) of 32.83 emu g−1 and soft magnetic behavior consistent with nanoscale ferrite nanocomposites. These findings demonstrate that agricultural waste-derived carbon materials can be effectively utilized to produce sustainable ferrite/rGO nanocomposites with promising potential for electromagnetic interference shielding, magnetic separation, sensing technologies, and other magnetic engineering applications.
5. Acknowledgments
The authors would like to express their sincere appreciation to the doctoral supervisors for their continuous support and valuable guidance in the completion of this article. This research was conducted as part of the doctoral program in the Electrical Engineering and Informatics Study Program at Universitas Negeri Malang. All authors have contributed substantially to the conception, research implementation, data analysis, and manuscript preparation, and have approved the final version of this paper for submission.
6. Data Availability
The datasets generated and analyzed during the current study, including the characterization data of Mn-doped Fe3O4/rGO nanocomposites derived from corncob biomass, are available from the corresponding author upon reasonable request.
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Edited by
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Associate Editor:
Jose Eiras.
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Editor-in-Chief:
Luiz Antonio Pessan.
