Featured Metal-Organic Framework Powders & Derivatives
Explore high-purity MOF grades ready for evaluation sample requests, OEM custom synthesis, and bulk contract manufacturing.
Understanding NH2-MIL-101(Fe): Structure, Chemistry & Benchmark Metrics
Amino-functionalized iron terephthalate, systematically designated as NH2-MIL-101(Fe) or $[Fe_3(\mu_3-O)(Cl/OH)(H_2O)_2(BDC-NH_2)_3]$, represents a major paradigm shift in industrial porous nanomaterials. Built from eco-friendly $Fe(III)$ oxo-clusters linked by 2-aminoterephthalic acid ($H_2BDC-NH_2$), this material combines ultra-high mesoporous surface area with dual-functional catalytic sites and tunable Lewis acid-base character.
Dual Mesoporous Cages
Constructed from giant rigid cages of approximately 29 Å and 34 Å with pentagonal and hexagonal windows (~12 Å and ~16 Å openings), allowing rapid mass transport of bulky organic pollutants and guest molecules.
Visible-Light Responsiveness
Direct excitation of the $-NH_2$ functional groups enables ligand-to-metal charge transfer (LMCT), narrowing the optical bandgap to ~2.0–2.2 eV and driving photo-Fenton chemistry under natural sunlight.
Eco-Friendly Iron Metal Nodes
Unlike chromium-based analogs (MIL-101(Cr)), NH2-MIL-101(Fe) utilizes non-toxic, earth-abundant iron nodes, adhering strictly to global REACH regulations and green chemistry directives for industrial effluent treatment.
Comparative Technical Matrix: NH2-MIL-101(Fe) vs Commercial Adsorbents & MOFs
| Performance Characteristic | NH2-MIL-101(Fe) | MIL-101(Cr) | UiO-66(Zr) | ZIF-8 (Zn) | Activated Carbon (Std) |
|---|---|---|---|---|---|
| BET Surface Area ($m^2/g$) | 1,800 – 2,600 | 3,000 – 3,800 | 1,100 – 1,500 | 1,300 – 1,800 | 800 – 1,200 |
| Optical Band Gap ($eV$) | ~2.1 (Visible Active) | ~3.8 (UV Only) | ~3.9 (UV Only) | ~4.9 (UV Only) | N/A (Opaque) |
| Pore Window Size | 12 Å / 16 Å (Mesoporous) | 12 Å / 16 Å (Mesoporous) | 6 Å (Microporous) | 3.4 Å (Microporous) | Bimodal / Disordered |
| Toxicity & Eco-Profile | Excellent (Iron Node) | Restricted ($Cr^{VI}$ Risk) | Good (Zirconium Node) | Moderate (Zinc Leach) | High Chemical Inertness |
| CO2 Affinity ($mmol/g, 1 bar$) | 3.2 – 4.5 | 1.8 – 2.4 | 2.1 – 2.8 | 0.8 – 1.2 | 1.0 – 1.5 |
| Photo-Fenton Catalytic Rate | Ultra-High ($k > 0.08 min^{-1}$) | Negligible | Negligible | Negligible | Inactive |
Global Commercial & Industrial Status of NH2-MIL-101(Fe)
The commercial adoption of iron-based metal-organic frameworks is transitioning rapidly from kilogram-scale pilot research into multi-ton industrial deployment across North America, Western Europe, and Asia-Pacific.
Regulatory Compliance Drivers
Strict European Union REACH policies and US EPA drinking water standards on toxic heavy metals are forcing industrial water treatment plants to phase out chromium, lead, and tin catalysts in favor of biocompatible, iron-based frameworks like NH2-MIL-101(Fe).
Industrial Scale-Up Bottlenecks
Historically, high organic linker costs ($2-aminoterephthalic\, acid$) and reliance on toxic N,N-dimethylformamide (DMF) solvents restricted production. Today's leading suppliers utilize hydro-thermal, solvent-free, or ethanol-assisted green continuous-flow technology.
Regional Demand Dynamics
North America and Europe lead in advanced decarbonization and direct air capture (DAC) pilot integration, while Asia-Pacific (spearheaded by China) dominates raw mass production, custom functional dispersion formulations, and industrial textile effluent treatment.
Deep-Dive: Industrial & Localized Application Scenarios
NH2-MIL-101(Fe)'s unique combination of amino functionality and coordinatively unsaturated iron centers makes it a versatile solution across five strategic macro-industries.
Solar Photo-Fenton Wastewater Treatment
In industrial textile and pharmaceutical manufacturing plants, recalcitrant micropollutants such as tetracycline antibiotics, PFAS "forever chemicals", and azo dyes resist conventional activated sludge systems.
Mechanism: NH2-MIL-101(Fe) acts as a visible-light-driven heterogenous Photo-Fenton catalyst. Upon solar irradiation, the amine group transfers electrons to the $Fe(III)$ core, reducing it to $Fe(II)$. This continuously activates trace hydrogen peroxide ($H_2O_2$) or persulfate ($PS$) to generate hydroxyl ($\cdot OH$) and sulfate radicals ($\cdot SO_4^-$), achieving over 98% degradation efficiency in under 45 minutes.
Flue-Gas CO2 Capture & Separation
Petrochemical processing facilities and fossil-fuel generation plants require energy-efficient carbon capture sorbents to replace liquid amine scrubbers (e.g., MEA), which suffer from severe corrosion and high thermal regeneration penalties.
Mechanism: The pendant amino ($-NH_2$) groups create localized dipole moments and hydrogen-bonding channels that selectively adsorb polar $CO_2$ quadrupoles over non-polar $N_2$ or $CH_4$. NH2-MIL-101(Fe) provides a high $CO_2/N_2$ selectivity ratio (>35:1) while lowering regeneration heat requirements by up to 40% compared to aqueous monoethanolamine.
Heavy Metal Oxyanion Remediation
Municipal drinking water providers and electronic waste recyclers encounter stringent limits for toxic hexavalent chromium ($Cr(VI)$), arsenate ($As(V)$), and lead ($Pb(II)$).
Mechanism: Under acidic or neutral pH conditions, the surface amino groups undergo protonation to form $-NH_3^+$, establishing strong electrostatic attraction for anionic species ($Cr_2O_7^{2-}$, $H_2AsO_4^-$). Simultaneously, open iron coordination sites bind heavy metal ions directly via inner-sphere complexation, achieving adsorption capacities exceeding $250 \, mg/g$.
Tandem Heterogeneous Catalysis
Fine chemical and API synthesis lines seek single-stage catalysts capable of mediating multi-step reaction cascades without intermediate isolation.
Mechanism: NH2-MIL-101(Fe) inherently possesses dual acid-base character: the $Fe(III)$ metal nodes act as strong Lewis acid sites, while the uncoordinated amino groups function as Brønsted/Lewis bases. This enables highly efficient tandem reactions such as Deacetalization-Knoevenagel condensations and selective oxidation of sulfides to sulfoxides under ambient pressure.
Lithium-Sulfur Battery Cathode Matrix
Next-generation energy storage manufacturers are working to eliminate the "polysulfide shuttle effect" that degrades capacity in high-density Lithium-Sulfur (Li-S) batteries.
Mechanism: Pyrolyzed or composite derivatives of NH2-MIL-101(Fe) act as porous host matrices. The nitrogen-doped carbon structure retains high electrical conductivity, while polar iron-nitrogen ($Fe-N_x$) sites chemically anchor lithium polysulfides ($Li_2S_x$), preserving capacity over 1,000 charge-discharge cycles.
Technical Roadmap: From Laboratory Synthesis to Ton-Scale Supply
Transitioning NH2-MIL-101(Fe) from academic research samples to reliable industrial shipments requires rigorous engineering controls across three distinct phase horizons.
Solvent Replacement & Recycling
Traditional DMF-based microwave synthesis is replaced by water-ethanol or ionic-liquid solvent systems. High-efficiency solvent recovery loops recycle >95% of organic liquor, driving down costs and reducing VOC environmental footprints.
Industrial Monolith Processing
Raw microcrystalline powders suffer from pressure drop issues in fixed-bed reactors. Using specialized clay/binder systems or electrospun polymer composite arrays, powders are shaped into 3mm extrudates, beads, or honeycombs without pore-blockage or surface-area loss.
Rigid COA & Batch Consistency
Industrial supply contracts are validated by strict quality analytics: Powder X-Ray Diffraction (PXRD) for crystal phase verification, Nitrogen Physisorption ($77K$) for BET surface area, Thermogravimetric Analysis (TGA) for thermal stability up to 300°C, and ICP-OES for trace metal verification.
Macro Industry Solutions & Turnkey MOF Integrations
Top suppliers do not merely ship raw powders; they partner with engineering EPCs to integrate NH2-MIL-101(Fe) into functional, modular hardware solutions.
Continuous Flow Wastewater Skids
Turnkey Photo-Fenton reactors equipped with solar-concentrating light tubes and packed-bed NH2-MIL-101(Fe) extrudate modules, capable of treating up to $500 \, m^3/day$ of pharmaceutical effluent with zero secondary sludge generation.
Modular VPSA Carbon Capture Units
Vacuum Pressure Swing Adsorption (VPSA) skids engineered specifically for biogas upgrading ($CO_2/CH_4$) and industrial boiler flue gas treatment, utilizing shaped MOF pellets for low-energy pressure swing regeneration cycles.
Specialty Gas Purifiers for Electronics
Ultra-high purity gas polishing filters filled with custom activated NH2-MIL-101(Fe) formulations to remove ppb-level polar impurities, moisture, and acid gases from semiconductor feed streams.
How to Evaluate & Audit NH2-MIL-101(Fe) Suppliers
Due to the delicate nature of reticular chemistry synthesis, choosing the right supplier is critical to prevent batch-to-batch variation and structural degradation.
1. Crystallinity Verification
Demand full-spectrum PXRD data matching published CIF files to ensure complete framework assembly without amorphous phase impurity contamination.
2. Residual Solvent Content
Verify that activation procedures remove trapped unreacted linker ($BDC-NH_2$) and high-boiling solvents (DMF) which block active $Fe$ sites and drastically reduce BET performance.
3. Scalability & Lead Times
Audit vendor production capacity: Can they transition seamlessly from 100g sample testing to 500kg commercial orders without changing structural specifications?
4. Customization Options
Confirm if the supplier offers tailored particle sizing (nano vs micro), functional dispersions (water/organic media), or binder-supported extruded pellets.
Frequently Asked Technical & Procurement Questions
Comprehensive technical insights compiled by senior R&D scientists and industrial procurement specialists.
What is the exact chemical formula and molecular structure of NH2-MIL-101(Fe)?
NH2-MIL-101(Fe) has the chemical formula $[Fe_3(\mu_3-O)(Cl/OH)(H_2O)_2(BDC-NH_2)_3]$, where $BDC-NH_2$ represents the 2-aminoterephthalate linker. It crystallizes in a cubic structure (space group $Fd\bar{3}m$) featuring iron octahedral trimers linked by amino-functionalized dicarboxylates, yielding two types of mesoporous cages (~29 Å and ~34 Å diameter) accessible through pentagonal (~12 Å) and hexagonal (~16 Å) pore windows.
How does the amine ($-NH_2$) modification enhance catalytic performance over un-functionalized MIL-101(Fe)?
The introduced $-NH_2$ group acts as an electron-donating auxochrome. It significantly narrows the optical bandgap of the MOF from ~3.1 eV (UV region) down to ~2.1 eV (visible light region, $\lambda < 550 \, nm$). Upon visible light absorption, the amino group facilitates Ligand-to-Metal Charge Transfer (LMCT), accelerating the photoreduction of $Fe(III)$ to $Fe(II)$, which greatly increases the rate of hydroxyl radical production during Photo-Fenton reactions.
What is the hydrothermal and thermal stability window for NH2-MIL-101(Fe)?
NH2-MIL-101(Fe) exhibits excellent thermal stability in dry air up to 280°C–300°C, above which organic linker degradation occurs. In aqueous solutions, it maintains structural integrity across a broad pH range of 2.5 to 8.5. Prolonged exposure to strongly basic conditions ($pH > 9$) can lead to framework hydrolysis due to hydroxide ion attack on the iron trimers.
Can NH2-MIL-101(Fe) be regenerated after organic contaminant adsorption or catalysis?
Yes. For adsorption applications, spent NH2-MIL-101(Fe) can be fully regenerated by mild solvent washing (using ethanol or acetone) or mild thermal vacuum baking at 120°C for 4–6 hours. In photo-catalytic processes, the framework self-cleans as adsorbed organic molecules are continuously mineralized into $CO_2$ and $H_2O$, enabling over 10 consecutive degradation cycles without significant loss of activity.
What forms are available for commercial purchasing?
Standard commercial grades are supplied as fine microcrystalline dry powders (average crystal size 100nm–500nm). Specialized suppliers also offer stabilized liquid dispersions (in ethanol, water, or DMF), extruded 3mm cylindrical pellets, porous beads for packed-bed columns, and custom electrospun membrane coatings.
How does NH2-MIL-101(Fe) compare to chromium-based MIL-101(Cr)?
While MIL-101(Cr) offers slightly higher total BET surface area ($>3000 \, m^2/g$), chromium is a hazardous heavy metal subject to severe environmental regulations (REACH, RoHS) due to carcinogenic $Cr(VI)$ toxicity concerns. NH2-MIL-101(Fe) utilizes eco-friendly iron metal nodes, exhibits visible light activity (whereas MIL-101(Cr) requires UV light), and is suitable for environmental discharge applications.
What testing procedures should be performed upon receiving bulk shipments?
Quality inspection should include: 1) Nitrogen physisorption ($77K$) to confirm BET surface area exceeds specified thresholds ($>1800 \, m^2/g$); 2) PXRD peak position analysis at $2\theta = 2-10^\circ$ to confirm cage crystallinity; 3) TGA analysis to verify removal of residual activation solvents; and 4) UV-Vis diffuse reflectance spectroscopy (DRS) to confirm bandgap performance.
Are free evaluation samples available for corporate R&D teams?
Yes. Qualified enterprise development teams and academic research labs can request 1g to 5g evaluation sample kits accompanied by full Certificate of Analysis (COA) documents. Inquire directly with technical sales engineers to specify required mesh size and solvent history.
Explore Related Metal-Organic Framework Formulations
Browse our broader range of commercial MOF powders, including ZIFs, MILs, and customized functional variants.
