Synthesis Of Nanoscale Zero-valent Iron Research Articles

Synthesis of nanoscale zero-valent iron doped carbonized zeolitic imidazolate framework-8 for methylene blue removal in water

Abstract Nanoscale zero-valent iron-doped carbonized zeolitic imidazolate framework-8 (nZVI/CZIF-8) was prepared by carbonation of ferric nitrate and ZIF-8 at 800 °C and used as an adsorbent to remove methylene blue (MB) from water. The synthesized nZVI/CZIF-8 has a specific surface area of 806.9 m2/g, a pore volume of 0.86 cm3/g and an nZVI content of 1.35%, respectively. Both the nZVI/CZIF-8 and CZIF-8 have identical functional groups of O-H, C-H and C=C. With the increase of CZIF-8 size, MB removal rate increased. The doping of nZVI increased the MB removal percentage from 74.5% for ZIF-8 to 96.2% within 80 min for nZVI/CZIF-8. The MB removal percentage increased with the dosage of nZVI/CZIF-8. The MB adsorption with the adsorbents conforms to the Freundlich adsorption isothermal model and the removal rate fitted well to a pseudo-first-order model. The results demonstrate the feasibility of synthesizing high active and stable nZVI/CZIF-8 particles.

Synthesis of Nanoscale Zero-Valent Iron with Polyphenol Extract from Cloves (Syzygium aromaticum) Through a Stepwise Reaction and Adsorption Test on Pb(II)

Polyphenols from clove extract (Syzygium aromaticum) were successfully used as reducing agents to synthesize nanoscale zero-valent iron (nZVI). Optimization of nZVI synthesis was carried out by reacting polyphenols and FeSO4 at a composition of 0.25:4.75, 1:4, 2:3, and 3:2. The particle size analyzer showed that the smaller particle size distribution was obtained at nZVI 0.25:4.75, with values of D10 = 85.1 nm, D50 = 122 nm, and D90 = 175 nm. The results of the Pb(II) removal test showed that nZVI 0.25:4.75 had a fairly high percentage of Pb(II) removal, which was 96.4852% at 60 minutes. The smaller particle size of nZVI 0.25:4.75 compared to other samples is an important factor affecting the adsorption activity of Pb(II) in an aqueous medium.

Green Synthesis of Nanoscale Zero-Valent Iron and Its Activity as an Adsorbent for Ni(II) and Cr(VI)

Zero-valent iron nanoparticles (nZVI) were successfully synthesized by metal salt reduction method using cinnamon as a reductor agent. Particle size analysis showed that the most optimum composition of FeSO4 and polyphenols was at a ratio of 4:1, resulting in Dv(10), Dv(50), and Dv(90) values of 23.7 nm, 44.6 nm, and 178 nm, respectively. Scanning electron microscopy showed that nZVI was spherical and agglomerated. X-ray diffraction pattern showed a peak at 45.03˚ that corresponds to nZVI. The batch test showed that nZVI has Ni(II) and Cr(VI) adsorption activity of 95.58% Ni and 64.29%, respectively.

Novel synthesis of nanoscale zero-valent iron from iron ore tailings and green tea for the removal of methylene blue

There are comparatively abundant Fe resources remained in iron ore tailings, which is urgent to be utilized comprehensively. In this work, nanoscale zero-valent iron (T-nZVI) was firstly synthesized with iron ore tailings and green tea as raw materials to realize the efficient removal of methylene blue (MB). The formation process of T-nZVI composite nanoparticles in complex system was investigated, as well as the effect of green tea extract dosage and pH value on its composition, particle size and reactivity. The characterization results indicated that the synthesized T-nZVI nanoparticles were amorphous spherical particles, which were composed of Fe0-Al2O3 core-shell structure capped with organic substance. The removal efficiency of MB by T-nZVI nanoparticles synthesized at optimal conditions could be up to 99.46%, which was better than the nZVI nanoparticles synthesized from chemical reagent. The decolorization mechanism might be related to adsorption, reductive degradation and complex precipitation between MB molecules and T-nZVI nanoparticles. This study proposes a feasible alternative utilization of iron ore tailings to prepare high value-added nanomaterials for wastewater treatment.

Removal of Trichloroethylene from Water by Bimetallic Ni/Fe Nanoparticles

Chlorinated organic solvents (COSs) are a significant threat to human beings. In this study, nanoscale bimetallic Ni/Fe particles were synthesized from the reaction of sodium borohydride (NaBH4) with the reduction of Ni2+ and Fe2+ in an aqueous solution. The synthesized nanoscale zero-valent iron (nZVI) and Ni-nZVI were characterized by SEM (scanning electron microscopy), XRD (X-ray diffractometer), Brunauer–Emmett–Teller (BET), and transmission electron microscopy (TEM). The removal performance of trichloroethylene (TCE) over the nZVI catalyst and Ni-nZVI was evaluated. Ni-nZVI with different Ni contents exhibited good reactivity towards the dechlorination of TCE over a 1h period, and the pseudo-first-order rate constant for TCE dechlorination by Ni-nZVI was 1.4–3.5 times higher than that of nZVI. Ni-nZVI with 5 wt% Ni contents exhibited the best dechlorination effect; the removal rates of TCE and its by-product dichloroethylene (DCE) were 100% and 63.69%, respectively. These results indicated that the Ni nanoparticles as the second dopant metal were better than nZVI for TCE degradation. This determination of the optimal Ni-NZVI load ratio provides a factual and theoretical basis for the subsequent application of nano-metal binding in the environment.

One-step synthesis of nanoscale zero-valent iron modified hydrophobic mesoporous activated carbon for efficient removal of bulky organic pollutants

It is of vital importance for industrial applications by developing simple, robust, economic, eco-friendly and easy scale-up methods for fabricating hydrophobic mesoporous activated carbon (MAC) from sustainable raw materials with high adsorption performance for bulky organic pollutants removal. Herein, a novel one-step facile approach coupling carbothermal reduction with catalytic activation was firstly established for preparing the coconut shell-based hydrophobic MAC modified with nanoscale zero-valent iron (NZVI@MAC). The in-situ synthesized NZVI (merely 0.33 wt%) by carbothermal reduction could not only catalyze the gasification reaction between carbon and CO2 to fabricate MAC (dBET = 5.17 nm, SBET = 933.12 m2 g−1), but also catalyze the amorphous carbon to form hydrophobic graphitic layers covering its surface. In striking contrast to the unmodified activated carbon, the NZVI@MAC surprisingly exhibited a remarkably 8.62-fold higher initial adsorption rate and a slightly increased adsorption capacity of 327.60 mg g−1 for bisphenol A (BPA). Intriguingly, the high mesoporous proportion (70–90%) of NZVI@MAC with the average pore size of 4.1–5.2 nm was effective in reducing the diffusion resistance for BPA. Such high adsorption performance under neutral conditions was primarily attributed to the strong hydrophobic interaction, π-π interaction and the weak hydrogen bonding. Moreover, the NZVI@MAC showed robust anti-interference properties in actual environmental conditions containing various inorganic ions and in a wide pH range (3–10). Therefore, the cost-effective, eco-friendly, sustainable and recyclable hydrophobic NZVI@MAC with stable structure and excellent performance for bulky organic adsorption is a promising material for practical applications, especially in drinking water purification.

Degradation of the mixed organic solvents of tributyl phosphate and n-dodecane by heterogeneous Fenton-like oxidation using nanoscale zero-valent iron as the catalyst

The treatment and disposal of spent radioactive organic solvents, i.e., tributyl phosphate (TBP) and diluent (such as kerosene, n-dodecane, etc.), produced in the reprocessing of spent fuel in the closed cycle are crucial for the sustainable development of the nuclear industry. In this study, the synthesized nanoscale zero-valent iron (nZVI) was used as the heterogeneous Fenton-like catalyst to promote the generation of hydroxyl radicals (•OH) by reacting with H2O2 to degrade the mixed organic solvents of TBP and n-dodecane. nZVI was characterized by scanning electron microscopy (SEM), nitrogen adsorption/desorption isotherms, and X-ray photoelectron spectroscopy (XPS) to investigate the micro-morphology, nano-particle size, and surface valence state. The change of Fe2+/Fe3+ concentration ratio during the reaction was measured to clarify the performance of nZVI. The effects of temperature, catalyst dosage, H2O2 dosage, and acidifier concentration on the degradation of TBP and n-dodecane were studied, and the results were complemented by the COD of the aqueous solution and the volume reduction rate of the organic phase. The mixed organic solvents of TBP and n-dodecane containing Co2+ were used to simulate the spent radioactive organic solvents and to study the distribution of nuclides after the reaction. The results showed that most of the radioactivity was in the residual solution, and the condensate contained almost no radioactivity. The degradation of TBP and n-dodecane was carried out separately, which showed that n-dodecane was more difficult to degrade. Density functional theory (DFT) calculations were applied to determine the adsorption energy of organic solvents and nZVI. According to the Fourier transform infrared spectra (FTIR) and their corresponding DFT calculations, liquid chromatography-mass spectrometry (LC-MS) and gas chromatography-mass spectrometry (GC-MS) of the sample after the reaction, the possible intermediates were analyzed, and the degradation mechanism was speculated.

Modification of nZVI with a bio-conjugate containing amine and carbonyl functional groups for catalytic activation of persulfate

Although the catalytic activation of persulfate by iron is now common in environmental sciences, there are still several obstacles, including the non-selectiveness and high cost of the production of the iron catalyst. Therefore, it is essential to develop fast and easy methods for producing an iron catalyst that exhibits high surface area properties and rapid catalytic activation of persulfate. In the present work, a chitosan-poly(3–hydroxybutyrate) conjugate (CS-PHB) was used to improve the synthesis of nanoscale zero-valent iron (nZVI). CS-PHB possesses among others two functional groups (carbonyl and amine) that are desirable for catalytic applications, including heterogeneous persulfate activation. The produced CS-PHB-nZVI particles showed an extensive surface area (113 m2/g) and, at the same time, superior activity in heterogeneous catalysis, which was tested and compared with others persulfate activation methods (heat, Fe2+, commercial nZVI). The most suitable activation conditions for complete degradation of 0.15 mM of the model pollutant (methyl orange; MO) were determined (i.e., a pH of 7, persulfate and CS-PHB-nZVI concentrations of 2 mM and 50 mg/L, respectively). The role of temperature in MO oxidation was evaluated by the Arrhenius equation, and the results showed that the estimated activation energy (Ea) was 27.1 kJ/mol. The MO degradation may be attributed to the generation of SO4− in the system as a result of scavenging tests. A magnet can be used to easily separate the remaining catalyst. It is believed that due to it having several advantages over traditionally used nZVI, CS-PHB-nZVI may be successfully applied for catalytic remediation of contaminants that are reactive towards sulfate radicals.

Iron coral: Novel fungal biomineralization of nanoscale zerovalent iron composites for treatment of chlorinated pollutants

In this research, a facile fungal biomineralization method was developed for the synthesis of nanoscale zerovalent iron (nZVI) with a unique N-doped branching structure, which showed excellent stability and mediated high degradation of carbon tetrachloride (CCl4) in aqueous solution. The ureolytic fungus Neurospora crassa was cultured in medium containing Fe2+ and urea which resulted in iron carbonate biomineral precipitation. Following carbonization at 900 °C, the fungal-carbonate composite became highly porous and granular nanoparticles (~50 nm diameter) were distributed evenly around the carbonized hyphae in a coralline manner. This ‘iron coral’ composite was identified as a mixture of zerovalent iron (Fe0), carbon iron (Fe1.91C0.09) and iron oxide (Fe3O4). The porous branching hyphal framework improved the capture efficiency of CCl4, and the N-doped sites may accelerate the electron transfer between CCl4 and nZVI. Geochemical simulation was applied to verify the formation of the biominerals, and chemical analyses confirmed its significant degradation ability for CCl4. These findings have therefore demonstrated that ureolytic fungi can provide a promising environmental-friendly system for the novel preparation of nZVI through biomineralization with the resulting ‘iron coral’ capable of significant removal of a chlorinated compound and therefore indicating new bioremediation applications.

Enhanced removal of vanadium(V) from groundwater by layered double hydroxide-supported nanoscale zerovalent iron

To reduce the toxicity of vanadium(V) [V(V)] and inhibit the desorption of adsorbed vanadium in groundwater, we synthesized nanoscale zerovalent iron (nZVI) dispersed on layered double hydroxide (LDH) composites (nZVI@LDH) to remove V(V) from simulated groundwater. We found that nZVI@LDH could reduce high-valence vanadium to low-valence vanadium, then forming vanadium-containing precipitation to reduce the toxicity and inhibiting vanadium from returning to groundwater. SEM and XRD characterizations exhibited the uniform dispersal of nZVI on the surface of LDH. nZVI@LDH with nZVI/LDH at a mass ratio of 1:2 provided the maximum adsorption capacity of 93.7 mg g−1 at pH 3.0. Coexisting anions and dissolved oxygen in groundwater have little effect on V(V) removal. nZVI@LDH performed well across a wide pH range (3.0–8.0). The surface characterizations and XPS analysis revealed that LDH as supporting materials inhibited the aggregation and passivation of nZVI. The adsorbed V(V) was reduced to V(IV) and V(III) by nZVI and spontaneously transformed into insoluble VO2 and V2O3. The DFT calculations indicated the strong complexation and better stability of the V(IV) and V(III) species with nZVI@LDH than V(V). This work suggests that nZVI@LDH has the potential to serve as an efficient material for the immobilization of V(V) in groundwater.

Study of the physicochemical surface alterations and incubation phenomena induced on iron targets by nanosecond pulsed laser ablation in liquids: Effect on productivity and characteristics of the synthesized nanoscale zero-valent iron (nZVI) particles

This work presents a systematic study of the significant role of the surface physicochemical alterations produced during the laser ablation of massive iron disks submerged in different solvents on the generation of colloidal iron nanoparticles. For that purpose, the laser ablation thresholds and the incubation coefficients for various pulse numbers per site and pulse energies have been measured under distilled water (DW) and ethanol (EtOH). After that, a complete physicochemical characterization of these targets indicated higher threshold fluence values for the ablation experiments conducted in EtOH than those performed in DW. The threshold fluence values decreased also with the decrease of the pulse overlap for both solvents, being it much more pronounced in EtOH. In addition, the related incubation coefficient showed that the incubation effect is lower for experiments conducted in DW. The characteristics of the synthesized nZVI particles were also a function of the solvent nature and the pulse overlap: laser ablation in DW leaded to iron oxide nanoparticles, whereas core-shell iron nanoparticles were obtained in EtOH. Moreover, high pulse overlap values lead to chemical alterations, resulting in a decrease of the composition homogeneity and a strong increase of the nanoparticle polydispersity.

Enhanced removal of aqueous Cr(VI) by a green synthesized nanoscale zero-valent iron supported on oak wood biochar.

Green nanoscale zero iron (nZVI) on an oak wood biochar support was prepared from tea polyphenol (TP-nZVI-OB), and applied to the removal of hexavalent chromium (Cr(VI)) from aqueous solution. The effects of experimental parameters on the Cr(VI) removal were evaluated by varying the Fe/C mass ratio, contact time, initial pH, and initial Cr(VI) concentration. The Cr(VI) removal performance of the TP-nZVI-OB was optimized at an Fe/C mass ratio of 2:1. The initial pH significantly affected the Cr(VI) removal, and 99.9% of the Cr(VI) was eliminated at pH 2.0. The kinetic data were well fitted to a pseudo-second order model, indicating that Cr(VI) removal was dominated by chemisorption. The successful TP-nZVI-OB synthesis and effective Cr(VI) removal mechanisms were confirmed by multiple techniques. The reaction between Cr(VI) and TP-nZVI-OB (2:1) involved multiple processes (sorption, reduction and co-precipitation), clarifying that TP-nZVI-OB is a potentially superior composite for Cr(VI) treatment of contaminated aqueous solution.

Synthesis of Nanoscale Zerovalent Iron (nZVI) Supported on Biochar for Chromium Remediation from Aqueous Solution and Soil.

Maize straw biochar-supported nanoscale zero-valent iron composite (MSB-nZVI) was prepared for efficient chromium (Cr) removal through alleviating the aggregation of zero-valent iron particles. The removal mechanism of MSB-nZVI was investigated by scanning electron microscopy with energy dispersive X-ray (SEM-EDX), X-ray diffractometry (XRD), and X-ray photoelectron spectroscopy (XPS). Cr(VI) removal from aqueous solution by MSB-nZVI was greatly affected by pH and initial concentration. The removal efficiency of Cr(VI) decreased with increasing pH, and the removal kinetics followed the pseudo-second-order model. XRD patterns of MSB-nZVI before and after reaction showed that reduction and precipitation/co-precipitation (FeCr2O4, Fe3O4, Fe2O3) occurred with the conversion of Cr(VI) to Cr(III) and Fe(0) to Fe(II)/Fe(III). The produced precipitation/co-precipitation could be deposited on the MSB surface rather than being only coated on the surface of nZVI particles, which can alleviate passivation of nZVI. For remediation of Cr(VI)-contaminated saline–alkali soil (pH 8.6–9.0, Cr 341 mg/kg), the released amount of Cr(VI) was 70.7 mg/kg, while it sharply decreased to 0.6–1.7 mg/kg at pH 4.0–8.0, indicating that the saline–alkali environment inhibited the remediation efficiency. These results show that MSB-nZVI can be used as an effective material for Cr(VI) removal from aqueous solution and contaminated soil.

Experimental evaluation of nitrate reduction from water using synthesis nanoscale zero-valent iron (NZVI) under aerobic conditions

The aim of this research was to study the potential of synthesized nanoscale zero-valent iron for nitrate reduction in aqueous solution. Batch technique was used to determine the kinetics and effective parameters. The effects of initial pH level, initial nitrate concentration and nanoscale Fe° concentration on nitrate reduction were studied. Nanoscale zero-valent iron was synthesized by chemical reduction method. The TEM image showed that synthesized nano Fe° has a size in the range of 40-120 nm. Experimental results exhibited that reduction efficiency of nitrate decreases with increasing initial pH and increases significantly due to increasing the concentration of zero-valent iron nanoparticles. Also, it was illustrates that initial concentration of nitrate has little effect on the nitrate reduction efficiency. Under acidic and neutral conditions, pH level of the reaction solution increased considerably after 60 min. However, under alkaline conditions, pH level of the reaction solution decreased. The reduction rate of nitrate reached 80% in 60 min with nanoscale Fe° dosage of 1.0 gl -1 and pH in4. The observed reaction rate constant was determined to be 0.0255 in min -1 for nanoscale concentration 1.0 gl -1. The experimental results indicated that the nitrate reduction with zero-valent iron nanoparticles do not comply the first-order reaction model with respect to nitrate concentration.

Synthesis of nanoscale zero-valent iron loaded chitosan for synergistically enhanced removal of U(VI) based on adsorption and reduction

In this study, chitosan (CS) loading well-dispersed nanoscale zero-valent iron (NZVI/CS) was successfully prepared via the liquid-phase reduction method. Characterizations of the NZVI/CS with high-resolution transmission electron microscopy and X-ray diffraction suggested that the as-prepared NZVI/CS comprised numerous dispersed Fe0 nanoparticles. Synergistic adsorption and reduction occurred during the removal process based on X-ray photoelectron spectroscopy and Fourier transform infrared spectroscopy. Influence of pH, contract time and temperature on U(VI) removal were investigated. The high removal capacity and rapid removal kinetics were predominately ascribed to the existence of well-distributed NZVI, which could rapidly reduce U(VI) into U(IV). The removal process could be better depicted by the Langmuir isotherm model and the pseudo-second-order kinetic model. The thermodynamic parameters showed that the removal process was exothermic. These findings indicate that the synthesized NZVI/CS composites have potential application for the removal of U(VI) from the sewage water.

Comparative Evaluation of Biosynthesized Nanoscale Zerovalent Iron and Iron-Oxide Nanoparticles in Mercury Adsorption

AbstractAn environmentally friendly approach was adopted in the synthesis of nanoscale zerovalent iron (NZVI) and iron oxide nanoparticles (Fe2O3). Plant extracts from aloe vera and myrtle were use...

Diversity in the species and fate of chlorine during TCE reduction by two nZVI with non-identical anaerobic corrosion mechanism

There have been many studies on TCE degradation by synthesized nanoscale zero-valent iron (nZVIB) and commercial nanoscale zero-valent iron (nZVIH), but the effect of anaerobic corrosion on the dechlorination pathways and speciation distribution of chlorine is still unclear. Compared with nZVIH, nZVIB has a faster degradation rate of TCE and formation rate of Cl−(aq) (kSA, TCE = 3.67 ± 0.85 × 10−4 & 2.17 ± 0.13 × 10−4 L·h−1·m−2 and kobs, Cl− = 0.344 ± 0.027 & 0.166 ± 0.010 μM·h−1 for nZVIB & nZVIH, respectively). Based on the characterization of XRD, XPS and TEM during the anaerobic corrosion, the corrosion of nZVIB was dramatic under the dissolution-reprecipitation mechanism; but that of nZVIH was moderate and inward by maintaining the core-shell structure and shaping slightly rough and lumpy surface. Due to the different corrosion products (FeOOH for nZVIB and Fe3O4/γ-Fe2O3 for nZVIH) and the catalysis of boron on the nZVIB surface, the preferential dechlorination pathway of TCE was not identical by hydrogenolysis (nZVIB) vs. reductive β-elimination (nZVIH). Meanwhile, the dechlorination pathway of nZVIH was similar to that of ZVI and the reductive pathway to acetylene bypassed the formation of more toxic VC. This study shows that the high reactivity of nZVIB results in rapid corrosion with the side effect of enhanced adsorption of VC while nZVIH has a stable core-shell structure and less sorbed chlorine, which provides a new sight to access the ecological risk of nZVI due to the overlooked effect of non-identical corrosion.

Glycerol-mediated synthesis of nanoscale zerovalent iron and its application for the simultaneous reduction of nitrate and alachlor.

NZVI has long been used for the remediation of different groundwater contaminants but their tendency to get oxidized easily has always been a barrier to their reductive ability. In this work, we have made an attempt to enhance the aerobic stability of the nanoparticles by synthesizing them in a medium consisting of a viscous solvent, glycerol, and water. The XRD analysis of the nanoparticles reveals that the particles prepared in the presence of glycerol have a very thin coating of iron oxides on the outer surface of the nanoparticles in comparison with those prepared in the aqueous medium. These nanoparticles were applied for the simultaneous reduction of two groundwater contaminants, nitrate ions, and alachlor, which is an herbicide. Stock solutions of these two contaminants were prepared and then they were mixed in varying amounts and were treated by different doses of the nanoparticle. The optimized dose of the nanoparticles obtained for almost 97% removal of both the contaminants is 2.05g/L. The studies showed that increasing the concentration of either of the contaminants while the other one was kept fixed led to a decrease in the removal efficiency. The studies conducted to see the effect of pH variation showed that the best removal can be achieved when the pH is 3 or even less than it, showing that acidic pH leads to higher removal values. Such nanoparticles which can be prepared easily at low-cost and can simultaneously act upon different contaminants are highly desired.

Green preparation of nanoscale zero-valent iron using clove extracts as adsorbent for lead removal

This paper reports our studies on the synthesis of nanoscale zero-valent iron (nZVI) for lead ions (Pb(II)) adsorbent. The nZVI was prepared using clove (Syzygium aromaticum) extracts as an environmentally-friendly reducing agent. Fourier transform infra-red spectroscopy (FTIR) studies indicate that eugenol is the main fraction found in the extracts used in this work. Dynamic light scattering (DLS) measurements show that relatively small particles with narrow size distribution were obtained by dropping the reducing agent gradually into the iron sulphate solution. The batch experiments showed that the as-prepared nZVI exhibits very high removal efficiency of Pb(II). The optimum adsorption time was reached differently for the adsorbent with different size distribution. The highest value is 96%, which was achieved at the adsorption time of 30 minutes by using CT-nZVI.

Decorating of ultra small and recyclable nanoscale zero-valent iron on NH2-SiO2 for enhanced high-performance removal of water pollutants

The synthesis of nanoscale zero-valent iron (NZVI) with dimensions ranging from 20 to 100 nm has received tremendous attention in the control of environmental pollutants. However, due to strong magnetic attraction and van der Waals forces of NZVI, creating well-dispersed and stable NZVI particles with subnanometre size while avoiding their aggregation and retaining surface activity is a challenge. Here, for the first time, a novel Fe0@NH2-SiO2 nanocomposite was prepared by making SiO2 amino-functionalization in a simple process of hydrolysis polymerization, grafting Fe3+ on NH2-SiO2 nanospheres, and reduction by sodium borohydrid. It was found that the surface of NH2-SiO2 nanospheres (around 200 nm) was uniformly decorated by plentiful of well-defined Fe0 nanoparticles with a diameter of <10 nm. The as-synthesized NZVI particles exhibited some unique features, such as ultra small size and excellent dispersibility, which significantly enhanced their reactivity in the removal of pollutants from water. Compared with the unsupported NZVI, these supported Fe0 nanoparticles showed a remarkable reduction activity in the application for the removal of water pollutants, and could be recycled easily with the aid of NaBH4.