Nickel Ferrite Nanoparticles Research Articles

Modification of nickel ferrite nanoparticles by sodium docusate surfactant for superior crystal violet dye removal from aqueous solutions.

In this study, nickel ferrite (NiFe2O4) nanoparticles were synthesized using the Pechini sol-gel method and modified with sodium docusate surfactant. The modified nanoparticles showed an enhanced adsorption capacity of 384.62mg/g for crystal violet dye, compared to 237.53mg/g for unmodified NiFe2O4. Characterization was performed using Fourier transform infrared spectroscopy (FTIR), X-ray diffraction (XRD), energy-dispersive X-ray spectroscopy (EDX), and scanning electron microscopy (SEM) techniques. The adsorption process was spontaneous, exothermic, and followed the Langmuir isotherm and pseudo-second-order kinetic model. Optimal conditions for maximum dye removal were achieved at pH 10, 50min, and 298K. Additionally, the synthesized adsorbents demonstrated excellent regeneration and reusability over five adsorption-desorption cycles with minimal efficiency loss.

Development and characterization of superparamagnetic Zn-Doped Nickel ferrite nanoparticles

The nanocrystalline Zn-doped Nickel ferrite nanoparticles, ZnxNi1-xFe2O4 (x = 0.2, 0.4, 0.6 and 0.8) have been developed using the sol–gel method. The average crystallite size was calculated using the Debye- Scherrer formula through X-ray diffractometry and found to be in the range of ∼ 4 nm to 7 nm. Rietveld refinement of the prepared samples suggested the cubic spinel phase of the nanoparticles. For the surface morphology analysis of the nanoparticles, the Field Emission Scanning Electron Microscope (FESEM) technique was utilized, which showed the spherical shape of the particles. Elemental Dispersive X-ray spectroscopy (EDAX) ascertained the experimentally obtained elemental composition with the calculated elemental composition and identified the elements present within the sample. Fourier Transform Infrared Spectroscopy (FTIR) revealed the two prominent absorbing bands, i.e., tetrahedral complex, υ1 and octahedral complex, υ2 in the range of 4000–300 cm−1. Photoluminescence spectroscopy and UV Visible diffuse reflectance spectroscopy determined the optical properties of the samples and it was observed that with the increasing concentration of Zinc, the value of band gap decreased from 2.29 eV to 2.11 eV. The M−H curves of the Zn-doped nickel ferrites exhibit superparamagnetic behavior at room temperature, confirming the presence of a single domain in the sample.

Starch-modified nickel ferrite nanoparticles as a magnetic nano-bio adsorbent for the extraction and determination of lead in water and Moringa oleifera samples

In this work, nickel ferrite magnetic nanoparticles were synthesized using a facile hydrothermal method. The surface modification of the prepared nanoparticles was carried out using cross-linked starch as a good stabilizer and biopolymer. The as-prepared nickel ferrite-starch nano-bio composite was characterized using numerous techniques, and introduced as a novel adsorbent. The initial experimental results indicated that the adsorbent has a good capability to extract lead ions (Pb(II)) from aqueous solutions. Hence, the adsorbent was applied for dispersive magnetic solid-phase extraction of Pb(II) before flame atomic absorption spectrometric detection. Some variables affecting the extraction efficiency such as sample volume (250.0mL), pH (6.5), type and eluent concentration (0.3molL1 nitric acid), amount of the adsorbent (200mg), extraction time (15min), and desorption time (15min) were investigated and optimized. Moreover, the adsorption capacity (35.50mgg1), stability and reusability (80 extraction/desorption cycles), and selectivity of the adsorbent towards the analyte were studied. In the optimized conditions, the linear dynamic range of the constructed calibration graph is between 0.5 and 140.0ngmL1. The limit of detection and limit of quantification of the method are 0.12 and 0.40ngmL1, respectively. The average intra-day and inter-day relative standard deviations (for n=6 and 5.0, 50.0 and 100.0ngmL1 Pb(II) concentration) are 2.02% and 3.72%, respectively. To validate the method, the certified reference material NIST SRM 1643e was analyzed, and the method was used for the pre-concentration and determination of lead ions in different sections of Moringa oleifera medicinal plant and several water samples. The acceptable relative recovery values between 98.0 and 102.7% were attained for the spiked samples, approving the ignorable matrix effect of the method.

Synthesis of 1,2,4-triazole-based deep eutectic solvents modified nickel ferrite nanoparticles and their application in dispersive solid phase extraction of triazole pesticides prior to LC-MS/MS analysis

A dispersive solid phase extraction method using new magnetic nanoparticles based on nickel ferrite was introduced for the extraction of six triazole pesticides (penconazole, hexaconazole, tebuconazole, diniconazole, triadimefon, and difenoconazole) from water samples before liquid chromatography-tandem mass spectrometry analyses. Initially, a new deep eutectic solvent was synthesized with 1,2,4-triazole and n-octanol for surface modification of the nanoparticles easily achieved through microwave radiation. The nanoparticles morphology, magnetic properties, adsorption capacity, isotherms, and crystalline patterns of the sorbent were examined. The capability of the sorbent was evaluated by extracting the target pesticides from water samples showing significant differences in adsorption capacity and efficiency between the modified and non-modified nanoparticles. High extraction recoveries (68-86%) were achieved for the analytes using small amounts of the sorbent with low limits of detection (0.03-0.08 ng mL-1) and quantification (0.13-0.29 ng mL-1), a wide linear range (0.29-250 ng mL-1), and acceptable precision (relative standard deviations ≤6.9%).

Hazardous effects of nickel ferrite nanoparticles and nickel chloride in early life stages of the freshwater snail Biomphalaria glabrata (Say, 1818).

Nickel ferrite nanoparticles (NiF NPs) have growing applications in biomedical and nanomedicine fields. However, knowledge concerning their ecotoxicity during the early developmental stages of invertebrates, such as gastropods, remains scarce. Thus, the current study aimed to evaluate whether NiF NPs and nickel chloride (NiCl2) induce toxic effects on embryos and newly hatched snails of freshwater species Biomphalaria glabrata (Say, 1818). NiF NPs were synthesized and characterized by multiple techniques, and their ecotoxicity was assessed by Biomphalaria embryotoxicity test (BET) during 144h of exposure and an acute toxicity test (96h) using newly hatched snails. NiF NPs induced mortality, developmental delay, reduced hatching rate, and promoted morphological changes in B. glabrata. Also, NiF NPs induced higher toxicity in embryos than in newly hatched B. glabrata. Overall, results showed that the early developmental stages of gastropods are a target group for nanoparticle toxicity in freshwater ecosystems.

Influence of the glycine/nitrites ratio on the anisotropy field of nickel ferrite nanoparticles

Nanosized particles of nickel ferrite were manufactured by the combustion method using different glycine/nitrites ratios. X-ray diffraction (XRD), transmission electron microscopy (TEM) and ferromagnetic resonance (FMR) showed, respectively, that the crystallite size, the particle size and the anisotropy field of the particles increased significantly as the glycine/nitrite rate increased. Magnetization and FMR data were used to determine the anisotropy constant and the cation distribution of the particles as functions of the glycine/nitrate ratio. The results could be useful to customize nickel ferrite nanoparticles for practical applications such as drug delivery, cancer therapy and supercapacitors.

Enhancement of Structural, Optical, and Electrical Properties of Hydroxypropyl Methylcellulose/Polyvinyl Alcohol Nanocomposites by Nickel Ferrite Nanoparticles for Optoelectronic Applications

Enhancement of Structural, Optical, and Electrical Properties of Hydroxypropyl Methylcellulose/Polyvinyl Alcohol Nanocomposites by Nickel Ferrite Nanoparticles for Optoelectronic Applications

Directional co-immobilization of artificial multimeric-enzyme complexes as a robust biocatalyst for biosynthesis curcumin glucosides and regeneration of UDP-glucose

Site-directed protein immobilization allows the homogeneous orientation of proteins while maintaining high activity, which is advantageous for various applications. In this study, the use of SpyCatcher/SpyTag technology and magnetic nickel ferrite (NiFe2O4 NPs) nanoparticles were used to prepare a site-directed immobilization of BsUGT2m from Bacillus subtilis and AtSUSm from Arabidopsis thaliana for enhancing curcumin glucoside production with UDP-glucose regeneration from sucrose and UDP. The immobilization of self-assembled multienzyme complex (MESAs) enzymes were characterized for immobilization parameters and stability, including thermal, pH, storage stability, and reusability. The immobilized MESAs exhibited a 2.5-fold reduction in UDP consumption, enhancing catalytic efficiency. Moreover, the immobilized MESAs demonstrated high storage and temperature stability over 21 days at 4 °C and 25 °C, outperforming their free counterparts. Reusability assays showed that the immobilized MESAs retained 78.7 % activity after 10 cycles. Utilizing fed-batch technology, the cumulative titer of curcumin 4’-O-β-D-glucoside reached 6.51 mM (3.57 g/L) and 9.45 mM (5.18 g/L) for free AtSUSm/BsUGT2m and immobilized MESAs, respectively, over 12 h. This study demonstrates the efficiency of magnetic nickel ferrite nanoparticles in co-immobilizing enzymes, enhancing biocatalysts' catalytic efficiency, reusability, and stability.

Comparative study of two different synthesis methods of nickel ferrite nanoparticles

Comparative study of two different synthesis methods of nickel ferrite nanoparticles

Terbium (III) and salicylamide doped nickel ferrite (NiFe2O4) nanoparticles synthesized from Olea europaea L. plant extracts via eco-friendly green synthesis approach and co-precipitation method

An eco-friendly and cost-effective NiFe2O4 nanoparticles and its derivatives NiFe2O4:salicylamide, NiFe2O4:salicylamide:Tb3+ and NiFe2O4:salicylamide:Tb3+:Olea europaea L. extracts have been successfully synthesized using a simple and refluxed-assisted chemical co-precipitation method and green route approach followed by thermal treatment steps. In this report, the structural, morphological, optical characteristics and biological activities of the nanoparticles were characterized by using XRD, SEM, FTIR, UV-Vis, PL, BET analysis, antibacterial assays and antioxidant activities. The results from XRD revealed that NiFe2O4 has a crystalline structure and EDX elemental mapping confirmed the uniform distributed of all the elements in the matrix. The incorporation of salicylamide, Tb3+ and Olea europaea L. extracts into NiFe2O significantly enriched the luminescence intensities and changed the emission colour coordinates. Colour tunability was achieved with luminescence ranging from bright blue emission to reddish orange light, which makes nanoparticles important candidates for solid-state lighting technologies. Combining olive leaf extracts with NiFe2O4 nanoparticles provided effective antioxidant and antibacterial activity by reducing and stabilizing of nanoparticles. Moreover, all experimental results reveal new ideas for the design and optimization of multifunctional nanomaterials with higher sensitivity and pave the way for the production of new functional nanomaterials.

Fabrication of eco-friendly NiFe2O4 nanocatalysts via plant extract-mediated synthesis: Kinetic and mechanistic insights into photocatalytic degradation of an anthraquinone dye and tetracycline antibiotic

The escalating peril of organic pollutant contamination in water, encompassing dyes and pharmaceuticals, requires the formulation of remediation approaches that are both sustainable and effective. This study addresses this challenge by exploring a bioinspired synthesis route for nickel ferrite nanoparticles (NiFe2O4 NPs) utilizing plant extracts. This eco-friendly approach eliminates the use of hazardous chemicals, promoting environmental sustainability compared to conventional methods. The plant extracts of Psidium guajava and Terminalia chebula were employed for the fabrication of NiFe2O4 NPs and the as-synthesized materials i.e. NiFe2O4 from Psidium guajava and NiFe2O4 from Terminalia chebula, were utilized for the photocatalytic degradation of Deep Blue and Tetracycline from aqueous systems under visible light illumination. The photocatalytic studies revealed the excellent potential of both the catalysts towards the efficient removal (>93 %) of model pollutants. The mechanistic elucidation of the developed system revealed the primary participation of hydroxyl radicals in the Fenton driven process. Furthermore, the developed materials exhibited reusability till multiple degradation cycles suggesting its potential applicability in real water systems. Comprehensively, this work paves the way for a sustainable idea of wastewater treatment, armed with nature inspired and eco-friendly photocatalysts.

Photocatalytic degradation of antibiotics by N-doped carbon nanoflakes-nickel ferrite composite derived from algal biomass

This work reports the synthesis of nickel ferrite (NiFe) nanoparticles, N-doped mesoporous carbon nanoflakes (NCF) and novel nickel ferrite-carbon nanoflakes (NiFe@NCF) nanocomposite using solvothermal method. NCF was derived from a cyanobacterial consortium consisting of Anabaena, Lyngbya and Weistiellopsis, rich in carbon and nitrogen. The synthesized nanoparticles were used as heterogeneous photocatalyst for degradation of two harmful water pollutants, ciprofloxacin (CIP) and levofloxacin (LEV). 99.91% LEV and 98.86% CIP were degraded within 50 and 70 min of visible light irradiation using NiFe@NCF following pseudo first order kinetics. This improved efficiency of the nanocomposite may be attributed to its higher surface area, reduction of band gap (from 2.42 to 2.19 eV), more active sites as well as charge carrier mobility with decreasing agglomeration tendency of the magnetic nickel nanoparticles upon being embedded on NCF. N-doping improves light harvesting property, retards charge recombination and extends as well as delocalises ᴨ-conjugated system resulting in enhanced photocatalytic activity. The scavenging experiments and EPR analysis reveal that O2−• and •OH are the main active species taking part in the degradation process. The material performs well within a wide range of pH and can be effectively used up to 5 repetitive cycles. A feasible photocatalytic degradation mechanism of the antibiotics against NiFe@NCF nanocomposite is also put forwarded along with their possible degradation pathways from LCMS studies.

Enhanced dielectric properties of copper substituted nickel ferrite nanoparticles for energy storage applications

In this study, it was aimed to obtain copper-substituted nickel ferrite nanoparticles, which are advantageous for use in energy storage devices such as batteries and supercapacitors that provide high energy storage capability with their high dielectric behavior, by co-precipitation method. Nickel ferrite nanoparticles in the form of CuxNi1-xFe2O4 containing copper substitution at ratios for x = 0.0, 0.2, 0.4, 0.6, 0.8, 1.0 were synthesized. X-ray diffraction Method (XRD) was used to analyze the spinel structure, the purity phase, and the crystalline size of the nanoparticles. Field Emission Scanning Electron Microscopy (FE-SEM), and Fourier Transform Infrared (FTIR) Spectroscopy were also performed to investigate the particle size, morphological distribution, and the functional groups of the samples. The structural analyses confirmed the successfully produced single-phase pure cubic spinel nickel ferrite and copper-substituted nickel ferrites with nanometer-scale particle distribution. The Impedance Spectroscopy technique was used for the characterization of the dielectric properties of the samples. Frequency-dependent complex dielectric, impedance, modulus, and alternating current (AC) conductivity mechanisms of the copper-doped nickel ferrite nanoparticles (CuxNi1-xFe2O4) were determined. The results showed that copper-induced nickel ferrite nanoparticles display a promising dielectric material consisting of grains and grain boundaries which are confirmed by Maxwell-Wagner interface-type polarization, which is in agreement with Koop's theory. Furthermore, a remarkable enhancement is obtained on the dielectric parameters of copper-induced nickel ferrites for x = 0.2, and it is seen that this is a critical value on the doping ratio. In addition, the dielectric parameters decreased between x = 0.2–0.8 ratios but still showed higher values than pure nickel ferrites, confirming that nickel ferrites have a tunable dielectric behavior depending on the stoichiometric copper doping ratios. Therefore, this may make them a promising dielectric medium for further studies in various electronic device applications.

Development of flexible, lead-free electrospun fibers comprising PVDF and NiFe2O4 for harvesting mechanical and stray magnetic fields

This research focuses on crafting highly flexible and efficient mechanical and magneto-mechano-electrical (MME) nanogenerators using electrospun poly (vinylidene fluoride)-nickel ferrite (PVDF-NiFe2O4) composite fibers, tailored for self-powered and wireless sensor networks. Nickel ferrite nanoparticles, averaging 40 nm in crystallite size, were synthesized through the autocombustion method and integrated as fillers within the PVDF matrix. Analysis via XRD and FTIR confirmed a greater presence of the ferroelectric β-phase in the PVDF electrospun fibers, accentuated by the incorporation of NiFe2O4. Notably, the mat containing 5 wt% of NiFe2O4 boasted an estimated 86 % β-phase. SEM micrographs depicted the formation of uniform bead-free fiber with a diameter of 900 nm. VSM analysis verified the ferrimagnetic properties of the composite fiber mats, registering a maximum saturation magnetization of 4.6 emu/cm3. Under mechanical tapping, the nanogenerator yielded an output voltage of 16.5 V and a power of 0.8 μW. The study also compared the performance of two MME nanogenerator geometries (rectangular and truncated) under an AC magnetic field of 10 Oe. Remarkably, the MME nanogenerator with a truncated geometry exhibited superior performance, generating 6.2 V, a 50 % increase over the rectangular counterpart.

Deciphering the influence of support in the performance of NiFe2O4 catalyst for the production of hydrogen fuel and nanocarbon by methane decomposition

Wet chemical synthesis route was used to synthesis nickel ferrite (NiFe2O4) nanoparticle. Later on the synthesized NiFe2O4 were supported on the surface of three traditional supports such as Al2O3, MgO and TiO2 to get NiFe2O4/Al2O3, NiFe2O4/TiO2 and NiFe2O4/MgO catalysts. The activity profile of each catalyst was evaluated in a fixed-bed reactor for direct methane decomposition at 800 °C. For both fresh and spent catalysts, many characterization techniques have been employed mainly XRD, FESEM, HRTEM, Raman spectroscopy, TGA, and nitrogen adsorption-desorption isotherm. X-ray powder diffraction studies revealed that all synthesized catalysts have a cubic spinel crystal structure. The XRD confirm the presence of NiFe2O4 particles in the component of fresh NiFe2O4/MgO, NiFe2O4/TiO2 and NiFe2O4/Al2O3 catalysts. Temperature Program Reduction (TPR) unveiled the presence of Ni oxides and Fe oxides by displaying reduction peaks in their respective temperature regions. The N2 adsorption-desorption isotherms of the fresh all catalysts reveal that these catalysts have a mesoporous structure. Activity data concluded NiFe2O4/MgO to be the most active catalysts among the tested catalysts methane conversion magnitude of 41.13 % and H2 formation rate of 84.40 × 10−5 mol H2 g−1 min−1. On the other hand, the H2 formation rate drastically declined and very poor activity of both NiFe2O4/TiO2 and NiFe2O4/Al2O3 catalysts was observed in the current work. XRD patterns, FESEM images and TGA analysis of spent NiFe2O4/MgO catalyst shown the filamentous carbon formation which secondarily confirm its higher activity, while its absence in catalysts of NiFe2O4/TiO2 and NiFe2O4/Al2O3. TGA analysis of the carbon deposited on the NiFe2O4/MgO catalyst showed that the amount of carbon was approximately 64 wt%. It was suggested that the formation of nickel-iron carbide revealed by XRD studies of spent catalysts may be the factor related to their poor activity while discussing the structure-activity relationship. Likewise, the higher degree of dispersion related to NiFe2O4/MgO as displayed by XRD, FESEM and TPR investigations, played a vital role in accelerating the rate of hydrogen formation.

Algae derived N-doped mesoporous carbon nanoflakes fabricated with nickel ferrite for photocatalytic removal of Congo Red and Rhodamine B dyes

A hydrothermal approach was employed to synthesize nickel ferrite (NiFe2O4) nanoparticles and its composite (NiFe2O4–NCF) with N-doped mesoporous carbon nanoflakes (NCF) where NCF acts as the catalytic support. The N-doped carbon nanoflakes were derived by pyrolyzing algae under Nitrogen atmosphere. These prepared materials were later probed with XRD, FESEM, TEM, BET, VSM, PL and UV–Vis spectrophotometry for their structural, morphological, magnetic and optical properties. The materials were used as photocatalysts to degrade two harmful textile dyes viz. Congo Red (CR) and Rhodamine B (RhB) under visible light at room temperature. Under optimized conditions, the pristine NiFe2O4 nanoparticle could degrade 95.34% and 98.24% CR and RhB respectively within 70 min while, the NiFe2O4–NCF nanocomposite showed degradation efficiency of 96.51% and 98.83% within 40 and 35 min of light irradiation respectively for CR and RhB dyes. The radical scavenging experiments indicated that electron and hole are the main reacting species that initiate the degradation of the dyes against the catalyst.

Preparation and Characterization of Nickel Ferrite (NiFe<sub>2</sub>O<sub>4</sub>) Nanoparticles by Surfactant-Free Electrochemical Method

Nickel ferrite (NiFe2O4) Nanoparticles have been synthesized by a simple surfactant-free electrochemical method at room temperature using iron plates as the cathode and anode electrode. nickel sulfate hexahydrate solution used as the electrolyte has a concentration of 0.04 M and pH 10. The voltage applied varied from 6, 9, and 12 V. We found that voltage and hydroxyl ions (OH-) presence have an important role in the formation of nickel ferrite nanoparticles. Particle size can be controlled by voltage. Nickel ferrite nanoparticles were produced in the form of gray powder and exhibited ferromagnetic properties. Material produced exhibits spinel oxide characteristics that confirms nickel ferrite presence. Nickel ferrite produced are nearly spherical with narrow size distribution having the size that can be classified as nanomaterial. Good electrochemical performance is legitimately observed for NiFe2O4 prepared in this work. This simple method is promising as a facile synthesis method for nickel ferrite nanoparticles.

A Study on Fine-Tuning the Optical Energy Band Gap and Various Optical Parameters with the Impact of Gadolinium Composition in NGFO Ferrite Nanoparticles

In the present work, gadolinium-doped nickel ferrite nanoparticles with the chemical composition NiFe2−xGdxO4 (X = 0.00, 0.05, 0.10, 0.15, 0.20, and 0.25) have been prepared by the sol-gel auto-combustion method and calcinated at 700 ∘C. The spinel ferrite phase formation was confirmed with the XRD graphs. In all the samples, the typical absorbance peak was observed in between 250–300 nm. Tauc plots were used to calculate the optical energy band gap, found in the range of 4.033–4.144 eV, and it was also calculated using x-ray density to be in the range of 3.690–4.300 eV. Both of them were observed in good agreement with each other, and we conclude that the Gd composition could finely tune the optical energy band gap. The impact of Gd composition was clearly observed on optical parameters. The refractive index, reflectivity, absorption coefficient, optical dielectric constant, and dielectric susceptibility have shown the increasing tendency from 2.1140 to 2.2325, 12.80 to 14.53%, 5.4380 to 6.3032 cm−1, 3.4690 to 3.9840 and 0.2760 to 0.3170, respectively, whereas the transmission coefficient decreased from 0.7730 to 0.7461.

Exploring the diverse performance of nickel and cobalt spinel ferrite nanoparticles in hazardous pollutant removal and gas sensing performance.

A simple sol-gel combustion process was employed for the creation of MFe2O4 (M=Ni, Co) nanoparticles. The synthesized nanoparticles, acting as both photocatalysts and gas sensors, were analyzed using various analytical techniques. MFe2O4 (M=Ni, Co) material improved the degradation of methylene blue (MB) under UV-light irradiation, serving as an enhanced electron transport medium. UV-vis studies demonstrated that NiFe2O4 achieved a 60% degradation, while CoFe2O4 nanostructure exhibited a 76% degradation efficacy in the MB dye removal process. Furthermore, MFe2O4 (M=Ni, Co) demonstrated chemosensitive-type sensor capabilities at ambient temperature. The sensor response and recovery times for CoFe2O4 at a concentration of 100ppm were 15 and 20, respectively. Overall, the synthesis of MFe2O4 (M=Ni, Co) holds the potential to significantly improve the photocatalytic and gas sensing properties, particularly enhancing the performance of CoFe2O4. The observed enhancements make honey MFe2O4 (M=Ni, Co) a preferable choice for environmental remediation applications.

High-Performance and Sensitive Humidity Sensors Based on Reduced Graphene Oxide/Nickel Ferrite Nanocomposites

This work reports the fabrication of highly sensitive humidity sensors using reduced graphene oxide (rGO), nickel ferrite nanoparticles (NiFe2O4 NPs), and their nanocomposites. rGO and NiFe2O4 NPs, obtained by the modified Hummers method and the wet chemical coprecipitation method, respectively, were used to synthesize rGO/NiFe2O4 nanocomposites at two different compositions. XRD analysis confirmed both the spinel structure of NiFe2O4 and the reinstatement of π-conjugated structure of graphene. Average crystallite sizes, calculated by XRD, were 17.80 nm, 13.60 nm, and 8.22 nm for NiFe2O4 NPs, rGO/NiFe2O4 (70/30), and rGO/NiFe2O4 (90/10), respectively. FTIR affirmed the successful reduction of graphene oxide to rGO. Optical bandgaps of 1.83 eV and 2.18 eV were obtained for rGO and NiFe2O4 respectively using Tauc plot. SEM confirmed the films’ porosity, providing more active sites for the adsorption of water molecules. Our results demonstrate that NiFe2O4 NPs show the highest response and sensitivity within the 35–90 RH% range. Additionally, the rGO/NiFe2O4 (70/30) nanocomposite achieved the fastest response/recovery time of 8/4 s at 100 Hz, with good repeatability and stability. These findings suggest that rGO/NiFe2O4 NCs are promising candidates for advanced humidity sensing applications due to their rapid response, sensitivity, and long-term reliability.