Green Synthesis Route Research Articles

Polydopamine-coated magnetic montmorillonite immobilized with potassium copper hexacyanoferrate for selective removal of Cs+ and its facile recovery

To address the challenges in remediating cesium contaminated aqueous environments, a low-cost, magnetically recoverable and superior composite adsorbent was fabricated based on the concept of magnetizing montmorillonite and entrapping potassium copper hexacyanoferrate that offers excellent selectivity for Cs+. The facile, green and scalable synthesis route involved exchanging the interlayer ions of montmorillonite with ferrous ions before oxidizing to form magnetic montmorillonite using a low-temperature hydrothermal method. The composite was then coated with polydopamine to be complexed with copper ions and subsequently reacted with the hexacyanoferrate precursor to in situ grow potassium copper hexacyanoferrate nanoparticles, thus forming the composite, D-Mt-Mag-HCF. The adsorbent exhibited excellent Cs+ sorption capacity (~159.2 mg/g) and Cs+ selectivity greater than 8.2 × 104 mL g−1 in concentrated brine. Moreover, the magnetic properties (17.4 emu/g) of the adsorbent facilitated its separation from contaminated aqueous environments once the adsorbent had removed Cs+. The current study demonstrates a novel and scalable production of a composite adsorbent that can be readily used to remediate contaminated water.

Green synthesis of ZnO/SiO2 nanocatalyst with palash leaves extract for treatment of petrochemical wastewater

The aim of this research work is Synthesis of ZnO/SiO2 with Palash leaves extract nanocatalyst by green synthesis route. Palash leaves extract contain a broad variability of bio-molecules which act as capping and reducing agents and increases the rate of reduction and stabilization of nanoparticles. Nanocatalyst synthesized by this method are eco-friendly and cheap. No work has been found on Butea monosperma (Palash) leaves extract with ZnO nanoparticles. This research work synthesis of ZnO/SiO2 with palash leaves extracts nanocatalysts has been made by using green synthesis route. This synthesized nanocatalyst was used for removal of COD (mg/l) and polycyclic aromatic hydrocarbons as pollutants from petrochemical industrial wastewater. The synthesized nanocatalyst of ZnO/SiO2 with palash leaves extract was characterized using BET surface area, FEG-SEM, EDAX, XRD, and FTIR. Results show that we have synthesized ZnO/SiO2 nanocatalyst with BET surface area 160.23 m2/g and SEM micrograph shows the spot of nano range particles. From SEM test it has been found that we synthesized ZnO/SiO2 nanoparticles in the range of 3 to 35 nm and average particle diameter is 15.8nm. XRD and EDAX result show that we have found nanoparticles of SiO2 and ZnO. FTIR results show that Zn-O, Si-O-Si stretching have been found at 1004.95, 861.24 cm-1 for ZnO and 1270.17 cm-1 for SiO2 respectively. Results shows that optimum percent removal of COD (mg/l) and acenaphthene (polycyclic aromatic hydrocarbon) as pollutant are 70 % and 79% respectably at 0.5g/500ml catalyst loading, at 30oC temperature for 4h reaction time. In Future this catalyst can be used to remove other PAH and phenolic compounds from petrochemical wastewater under visible light also and other industrial wastewater can also treat by this catalyst effectively. Copyright © 2018 VBRI Press.

Green route of flexible Al-MOF synthesis with superior properties at low energy consumption assisted by ultrasound waves

In this literature, it was successfully prepared metal-organic framework MIL-53(Al) for the first time at convenient conditions using sonication irradiation. Comparison of Sonochemical-assisted hydrothermal synthesis with conventional hydrothermal method had been investigated. Suitable morphology and unique porosity properties were obtained through Sonochemical-assisted approach, which has presented excellent features and good thermal stability for crystals samples with nano-sized particles versus the conventional hydrothermal method. Low reaction temperature of 150 °C and short time of synthesis 6 h investigated pure crystallinity of MIL-53(Al) via Sonochemical-assisted synthesis due to its ability to supply controlled amounts of energy to the solution that leads to increase nucleation rate and crystal growth. The characterization of samples was specified using X-ray diffraction (XRD), Scanning Electron Microscope (SEM), Fourier Transform Infrared Spectroscopy (FTIR), Nitrogen Adsorption Technique (BET) and Thermal Gravimetric Analysis (TGA). Highest surface area is nearly to 1363.5 m2/g, best thermal stability up to 600 °C, more uniform and narrower size distribution in the range of 0.7–0.93 μm at short sonication time 24 h and low temperature at 150 °C were observed.

Application of green synthesized WO3-poly glutamic acid nanobiocomposite for early stage biosensing of breast cancer using electrochemical approach

Biopolymer films have drawn growing demand for their application in the point of care domain owing to their biocompatibility, eco-friendly, and eligibility for in vivo analyses. However, their poor conductivity restricts their sensitivity in diagnostics. For high-quality electrochemical biosensor monitoring, two vital factors to be greatly paid attention are the effective merge of amplification modifiers with transducing surface and the superior linking across the recognition interface. Here, we introduce an enzyme-free electrochemical biosensor based on electrosynthesized biocompatible WO3/poly glutamic acid nano-biocomposites to address the hardships specific to the analysis of circulating proteins clinical samples. In addition to its green synthesis route, the poor tendency of both components of the prepared nano-biocomposite to amine groups makes it excellent working in untreated biological samples with high contents of proteins. Several electrochemical and morphological investigations (SEM, EDX, and dot mapping) were fulfilled to gain a reliable and trustful standpoint of the framework. By using this nanobiosensor, the concentration of HER-2 was detectable as low as 1 fg mL−1 with a wide linear response between 1 ng mL−1 and 1 fg mL−1. Meanwhile, the protocol depicted ideal specificity, stability, and reproducibility for the detection of HER-2 protein in untreated serum samples of breast cancer patients.

Green synthesis of copper oxide nanoparticles using extracts of Solanum macrocarpon fruit and their redox responses on SPAu electrode

In this work, CuO nanoparticles (NPs) were prepared from the aqueous extracts of Solanum macrocarpon fruit by using the conventional heating (CuO(h) NPs) and microwave irradiation (CuO(m) NPs) methods. The synthesized nanoparticles were characterized using scanning electron microscopy (SEM), transmission electron microscopy (TEM), and X-ray diffraction (XRD). The SEM analysis revealed that the CuO NPs from both routes contained essentially smooth surfaces, and displayed some degree of agglomeration. The TEM analysis confirmed some spherical morphology with mean particle sizes of 35.60 ± 6.24 nm and 47.14 ± 6.18 nm for the CuO(h) and CuO(m) NPs respectively. While the CuO(m) NPs possessed a single-phase consistent with the face cantered cubic structure of copper oxide, the CuO(h) NPs showed some extra peaks attributed to Cu2O NPs as secondary phase. Electrochemical studies were conducted in order to evaluate the electrochemical properties of the NPs. The responses of a gold screen-printed electrode surface treated with both NPs showed that their redox behaviours on (Fe(CN)6)3−/4− probe and KCl electrolytes vary significantly. In (Fe(CN)6)3−/4− probe, the SPAuE/CuO(h) showed enhanced electrochemical response relative to the bare, while the SPAuE/CuO(m) showed a lower current response than the bare. However, in the KCl electrolye, the SPAuE/CuO(h) and SPAuE/CuO(m) were highly electroactive and demonstrated peak current magnitude that was about 26.5 and 83.38 times higher than that of the bare. In this KCl medium, the magnitude of the oxidation peak current of Cu2+ for SPAuE/CuO(m) was about 3 times higher than that of SPAuE/CuO(h). The percentage contraction in redox coordinates between the 1st and 10th scans in both electrodes were 3.88 and 19.28% for SPAuE/CuO(h) and SPAuE/CuO(m) respectively. Thus, the choice of green synthesis route could be exploited in different fields where green NPs is desired.

ZnO and Simonkolleite Nanocomposite Synthesis via Green Chemistry Using Hibiscus Flower Extract

In the present work, zinc oxide (ZnO) and Simonkolleite (SK) nanocomposite was prepared using a facile green synthesis route, using hibiscus flower extract. Zinc chloride as starting solution was mixed with hibiscus plant extract. The zinc salt molarity was varied in order to investigate its effect on the synthetized nanocomposite structure. The synthetized nanocomposite were characterized by mean of X-rays diffraction (XRD), scanning electron microscopy (SEM), and transmission electron microscopy (TEM) and X-ray photoemission spectroscopy (XPS). The results indicated that the zinc chloride molarity plays a key role in zinc oxide and simonkolleite nanopowder synthesis. The increase in zinc salt molarity above 0.1 M yields to a pure simonkolleite. While, at low zinc salt molarity, the formed nanoparticles are composed of mixture of simonkolleite and ZnO. The thermal treatment causes a partial conversion of simonkolleite to ZnO.

Bionanocomposite of Au decorated MnO2 via in situ green synthesis route and antimicrobial activity evaluation

Green synthesis gaining a significant importance for the preparation of nanoparticles (NPs) and NPs-based biocomposites gained much attention in biological applications. In the current study, gold (Au) nanoparticles were prepared via green approach using cinnamon extract. The Au nanocomposite (NC) was prepared with MnO2 nanofiber mesh structure. The NC was characterized by XRD, SEM, FT-IR, EDX, UV–visible and DLS techniques. The MnO2 nanofibers diameter was in 10–25 nm range, which was arranged in a mesh form and Au NPs was combined with nanofibers randomly. The MnO2-Au NC antimicrobial activity was measured against Escherichia coli, Pseudomonas aeruginosa and Staphylococcus aureus strains. The antimicrobial activity of MnO2-Au NC was highly promising against tested microorganisms in comparison to control (ciprofloxacin, a standard drug). The antimicrobial activity of MnO2-Au NC was found in following order; > S. aureus > E. coli > P. aeruginosa with the zones inhibition of 22, 18 and 15 (mn), respectively. The MIC (minimum inhibitory concentration) values were 316, 342 and 231 (µg/mL) for E. coli, P. aeruginosa and S. aureus, respectively. In view of promising antimicrobial activity, the MnO2-Au NC prepared via green approach could have potential applications in medical field and future study can be engrossed on the biocompatibility evaluation of MnO2-Au NC using bioassays.

Synthesis of Al-Based Metal-Organic Framework in Water With Caffeic Acid Ligand and NaOH as Linker Sources With Highly Efficient Anticancer Treatment.

In this study, novel nanostructures of aluminum base metal-organic framework (Al-MOF) samples were synthesized using a sustainable, non-toxic, and cost-effective green synthesis route. Satureja hortensis extract was used as an effective source of linker for the development of the Al-MOF structures. The Fourier-transformed infrared (FTIR) spectrum confirmed the presence of characterization bonds related to the Al-MOF nanostructures synthesized by the green synthesis route. The scanning electron microscopy (SEM) and transmission electron microscopy (TEM) analyses revealed that the sample synthesized by Na2-CA was composed of multilayers, although it was agglomerated, but it had dispersed and occurred in spherical particles, indicating active organic matter. N2 adsorption/desorption isotherms demonstrated the significant porosity of the Al-MOF samples that facilitate the high potential of these nanostructures in medical applications. The anticancer treatment of Al-MOF samples was performed with different concentrations using the MTT standard method with untreated cancer cells for 24 and 48 h periods. The results exhibited the significant anticancer properties of Al-MOF samples developed in this study when compared with other MOF samples. Thus, the development of a novel Al-MOF and its application as a natural linker can influence the anticancer treatment of the samples. According to the results, the products developed in this study can be used in more applications such as biosensors, catalysts, and novel adsorbents.

Nanoprobes for Biomedical Imaging with Tunable Near‐Infrared Optical Properties Obtained via Green Synthesis

Ideally, any material used should be nontoxic and produced with safe, inexpensive, and energy‐effective processes. In the case of optically active nanoparticles, this is often not the case, as they are frequently composed of hazardous heavy metals and/or produced with methods far from being environmentally friendly. Herein, the preparation of Ag2S‐based nanoparticles via a simple green synthesis route is explored. Aqueous extracts of roasted coffee are used as sources of coordinating molecules. Optimization of the reaction conditions yields dimeric Ag−Ag2S nanoparticles, whose near‐infrared photoluminescence can be switched on via H2O2‐mediated oxidation. This oxidation transforms suitable photoacoustic contrast agents into fluorescence imaging probes. Theoretical calculations further clarify the role of metallic silver in determining the optical properties of Ag2S. Overall, it is demonstrated that nanomaterials with tangible applicative potential can be prepared via cost‐ and energy‐effective synthesis strategies that entail benign, renewable chemicals.

Green synthesis of MIL-100(Fe) derivatives and revealing their structure-activity relationship for 2,4-dichlorophenol photodegradation

MIL-100(Fe), a kind of iron-based metal-organic framework materials (MOFs), can be synthesized at room temperature or hydrothermal conditions, which are promising precursor materials for preparing photocatalysts to degrade some recalcitrant chlorophenols in industrial wastewater. However, the relationship between the structural characterization of MIL-100(Fe) derivatives and their photodegradation behavior of chlorophenol pollutants is still unclear. Thus, in this work, a porous Z-scheme α-Fe2O3/MIL-100(Fe) composite was successfully fabricated via partial-pyrolysis of MIL-100(Fe) precursor synthesized through green synthesis route, which was further used for degrading high-concentration of 2,4-dichlorophenol under visible-light illumination (λ > 420 nm). The effects of synthesis route and pyrolysis temperature of MIL-100(Fe) on the degradation efficiencies of as-derived materials for 2,4-dichlorophenol were investigated. The structure-activity relationship was illuminated in detail. Otherwise, the influence of several process factors, i.e., initial concentration and pH of the 2,4-dichlorophenol solution, catalyst dosage on the degradation efficiency of 2,4-dichlorophenol has also been performed. The removal efficiency of 2,4-dichlorophenol with the initial concentration of 100 mg L−1 reached up to 87.65% under optimized conditions. Lastly, the possible mechanism was explored based on trapping experiments and some other characterization results. The study in this paper not only exhibited new insight into the modified α-Fe2O3 material with high photocatalytic activity but also provided a promising method for treating wastewater containing 2,4-dichlorophenol or other similar organic pollutants.

PHENOL removal in refinery wastewater using mixed oxides prepared by green synthesis

Mixed solid oxides are known for their excellent catalytic property and applications in environmental remediation. This study presents a green-synthesis route for magnesium oxide–titanium oxide, a mixed oxide here demonstrated to possess high performance of phenol removal from hydrocarbon refinery process wastewater. Mixed oxide (MgO-TiO2) was prepared by using the whole extract from leaves of Piliostigma Thonningii as reducing agent. A structural attribute of the mixed oxide was investigated using X-ray Diffractometer, High-Resolution Scanning Electronic Microscopy and Energy Dispersive X-ray. Petroleum refinery raw wastewater having phenol concentration of 19.961 mg/L was treated using the green-synthesized mixed oxide. Adsorptive phenols removal up to 99.5% was achieved with a dosage of 0.04 g/100 mL at temperature of 35 °C, and contact time of 1.167 h. By this, the treated water meets the standard acceptable phenol concentration (0.1 mg/L) in wastewater of hydrocarbon refinery.

Comparative studies of the biological efficacies of Ag and Ag-MgO nanocomposite formed by the green synthesis route

The present study investigates the changes occurring to the physicochemical and biological properties of silver (Ag) nanoparticles (NPs) before and after conjugating with that of magnesium oxide (MgO). In that view, to form Ag NPs and Ag-MgO nanocomposite, we adopted a green synthesis route that makes use of Citrus paradisi(grapefruit red) extract as a reducing agent and the formed particles are thoroughly characterized for the crystallinity, surface bonding and functionality, morphology, composition, surface charges, etc. From the physicochemical analysis, the successful formation of Ag and Ag-MgO composites are confirmed from the UV–Vis and FTIR spectroscopy, while the TEM indicated the spherical morphology and DLS for the average particle size of 260 nm in solution. Further, on testing the biological efficacy, the Ag-MgO nanocomposite (up to 320 µg/mL) was found to have efficient antibacterial and antifungal activities against Staphylococcus aureus and Candida albicans (respectively). Also, the studies of β-galactosidase enzyme activity resulted that Ag’s composite formation with MgO (Ag-MgO with IC50 of 27.6 µg/mL) is not significantly enhancing the effectiveness as compared to pure Ag NPs (IC50 of 28.6 µg/mL). Also, the in vitro cell viability studies indicated the anticancer activity of Ag-MgO nanocomposite in a dose-dependent manner when tested against the Hela cancer cells was in the concentration range of 1–100 µg/mL (24 h period). Based on the overall analysis, the easy making process by the green synthesis route and inexpensive Ag-MgO nanocomposite can serve as a superior antimicrobial and anticancer ingredient for the development of therapeutic products in the biomedical sector.

Albumen-assisted Synthesis of Nanocrystalline Nickel Ferrite Photocatalyst

Abstract: As a simple step to remove the polluting dyes in aqua ecosystem, NiFe2O4 nanoparticles well known for their ferromagnetic properties, low conductivity and high electrochemical stability were prepared by simple auto combustion method using egg white as fuel via green synthesis route. The structural, morphological and magnetic properties of prepared NiFe2O4 was analyzed. The desirable phase purity of the prepared spinel ferrite was deliberated by X-ray Diffractometer (XRD), Fourier Transform Infrared Spectrometer (FTIR), Scanning Electron Microscopy (SEM), Energy Dispersive and Vibrating Sample Magnetometer (VSM). XRD predicts the phase formation, particle size and lattice parameter of the spinel ferrite. The FTIR spectrum confirms the ferrite structure. The morphological and elemental analysis was made using SEM and EDAX. The hysteresis curve reveals the magnetic properties, such as remanence magnetization (Mr), coercivity (Hc) and saturation magnetization (Ms). The photocatalytic efficiency of the synthesized samples was determined from degradation of methylene blue dye. The whole process was monitored using spectrophotometer at regular intervals of time. The maximum photocatalytic degradation efficiency for NiFe2O4 is around 95.6 %. Keywords: NiFe2O4, Ferrite, Green synthesis, Egg white, Combustion, Photocatalyst.

Green Synthesis of Metal and Metal Oxide Nanoparticles Using Different Plants’ Parts for Antimicrobial Activity and Anticancer Activity: A Review Article

Nanotechnology emerged as a scientific innovation in the 21st century. Metallic nanoparticles (metal or metal oxide nanoparticles) have attained remarkable popularity due to their interesting biological, physical, chemical, magnetic, and optical properties. Metal-based nanoparticles can be prepared by utilizing different biological, physical, and chemical methods. The biological method is preferred as it provides a green, simple, facile, ecofriendly, rapid, and cost-effective route for the green synthesis of nanoparticles. Plants have complex phytochemical constituents such as carbohydrates, amino acids, phenolics, flavonoids, terpenoids, and proteins, which can behave as reducing and stabilizing agents. However, the mechanism of green synthesis by using plants is still highly debatable. In this report, we summarized basic principles or mechanisms of green synthesis especially for metal or metal oxide (i.e., ZnO, Au, Ag, and TiO2, Fe, Fe2O3, Cu, CuO, Co) nanoparticles. Finally, we explored the medical applications of plant-based nanoparticles in terms of antibacterial, antifungal, and anticancer activity.

Fe Foam-Supported FeS2-MoS2 Electrocatalyst for N2 Reduction under Ambient Conditions.

Highly efficient catalysts with enough selectivity and stability are essential for electrochemical nitrogen reduction reaction (e-NRR) that has been considered as a green and sustainable route for synthesis of NH3. In this work, a series of three-dimensional (3D) porous iron foam (abbreviated as IF) self-supported FeS2-MoS2 bimetallic hybrid materials, denoted as FeS2-MoS2@IFx, x = 100, 200, 300, and 400, were designed and synthesized and then directly used as the electrode for the NRR. Interestingly, the IF serving as a slow-releasing iron source together with polyoxomolybdates (NH4)6Mo7O24·4H2O as a Mo source were sulfurized in the presence of thiourea to form self-supported FeS2-MoS2 on IF (abbreviated as FeS2-MoS2@IF200) as an efficient electrocatalyst. Further material characterizations of FeS2-MoS2@IF200 show that flower cluster-like FeS2-MoS2 grows on the 3D skeleton of IF, consisting of interconnected and staggered nanosheets with mesoporous structures. The unique 3D porous structure of FeS2-MoS2@IF together with synergy and interface interactions of bimetallic sulfides would make FeS2-MoS2@IF possess favorable electron transfer tunnels and expose abundant intrinsic active sites in the e-NRR. It is confirmed that synthesized FeS2-MoS2@IF200 shows a remarkable NH3 production rate of 7.1 ×10-10 mol s-1 cm-2 at -0.5 V versus the reversible hydrogen electrode (vs RHE) and an optimal faradaic efficiency of 4.6% at -0.3 V (vs RHE) with outstanding electrochemical and structural stability.

Structural, morphological and magnetic investigations on cobalt ferrite nanoparticles obtained through green synthesis routes

Structural, morphological and magnetic investigations on cobalt ferrite nanoparticles obtained through green synthesis routes

Synthesis of silver nanoparticles using aqueous extract of Cuscuta japonica seeds and their antibacterial and antioxidant activities

The green synthesis of silver nanoparticles (Ag NPs) using plant extract has been proposed as a facile, eco-friendly and cost-effective method. The Cuscuta japonica plant is one of the well-known medicinal plant and its seed have been reported for different biomedical applications. The present study reports the use of aqueous extract from seeds of C. japonica as a reducing agent and formation of Ag NPs from silver nitrate by a green synthesis route. The development of brown color in reaction mixture were observed visually, which indicates formation of Ag NPs. UV–visible spectroscopic peak about 460 nm confirms the synthesis of Ag NPs. The spherical shapes of synthesized Ag NPs were determined by transmission electron microscopy. Average particles size was found 73.22 ± 3.55 nm. The synthesis procedure was optimized by varying reaction time and temperature. The Fourier transform infrared spectroscopy spectrum reveals that the presence of components acts as a reducing and capping agents. The synthesized Ag NPs shows antioxidant activity by scavenging free radicals and antibacterial activity against human pathogens includes Gram-positive (Bacillus subtilis, Staphylococcus aureus) and Gram-negative (Escherichia coli) bacteria.

Green Route Synthesis of Copper Oxide Nanoparticles Against MCF-7 Cell Line (Breast Cancer)

Growing nanostructures by green synthesis is an attractive method with a lot of applications, such as antibacterial, anticancer, antifungal and water treatment, etc. Copper oxide nanoparticles have been fabricated using the extract of Aloe Barbandanum, famous with the name of Aloe vera. These nanoparticles are important due to their applications in medical sciences. Structural, optical, compositional, and morphological properties of synthesized nanoparticles were studied and reported here. The phases and crystallite size were determined using X-ray Diffraction and the UV-visb was used to find out the direct bandgap and the absorbance near the visible range. Fourier Transform Infrared Spectroscopy spectra confirmed the presence of a strong band of metal oxide near 606 cm-1. Using Scanning Electron Microscope the average grain size was obtained as small as 60 nm. These fabricated CuO NPs were tested for their possible uses against the MCF-7 cell line (breast cancer cells) and results are presented.

Metal free and sunlight driven g-C3N4 based photocatalyst using carbon quantum dots from Arabian dates: Green strategy for photodegradation of 2,4-dichlorophenol and selective detection of Fe3+

The fabrication of photocatalyst with a visible response and prolonged lifetime of charge carriers is a significant tactic to treat EDCs. In this work, a green synthesis route was adopted to prepare carbon quantum dots (CQDs) from Arabian dates (AD-CQDs) via hydrothermal method. The different weight percentages of fabricated AD-CQDs (10, 15 and 20 wt%) were coupled with graphitic carbon nitride (g-C3N4) to construct AD-CQDs/g-C3N4 composites to degrade 2,4-dicholorophenol (2,4-DCP) under sunlight irradiation with an average light intensity of ~973 × 100 lx. The obtained AD-CQDs were used as a highly selective sensor for ferric (Fe3+) ions, with a low detection limit of 1 nM. The increase loading of AD-CQDs resulted in particle agglomeration which decreased the specific surface area of g-C3N4 from 74.799 m2/g to 62.542 m2/g. The low specific surface area in the composites did not hamper the photocatalytic performance in which all composites showed a higher degradation rate than that of g-C3N4. With the optimum loading of AD-CQDs (20 wt%), the composite degraded 100% of 2,4-DCP in 90 min which was 1.7 times higher than g-C3N4 (59.48%). The excellent photocatalytic performance was mainly correlated to the effective separation of photogenerated electrons as evidenced by TRPL and transient photocurrent response. The second factor is visible light response because of the minor decrease of band gap energy as evidenced in UV–vis DRS spectra. Both factors are attributed to the dual functions of AD-CQDs as electron acceptors and photosensitizers. The simple and low-cost synthesis strategy could be an alternative to obtain sunlight driven photocatalysts without coupling with metal dopants or other semiconductors.

Tailoring growth of MOF199 on hierarchical surface of bamboo and its antibacterial property

Bamboo, as a fast-grown forest resource, can be functionalized by metal–organic frameworks (MOFs) with various potential applications. However, the stability of MOFs immobilized on bamboo surface remains to be improved. In this work, MOF199, as known as HKUST-1, was in situ anchoring on moso bamboo via regulating pretreatment of bamboo and a green two-step synthesis route. The two-step synthesis route was completed under room temperature and both precursor solutions can be reused. The results indicated that, with the collaboration of delignification and carboxymethylation pretreatment of bamboo, a dense and well-dispersed MOF coating was successfully synthesized, the adhesion between MOF199 and bamboo surface was also improved. Besides, the quantity and size of MOF199 on bamboo can be tailored by tunning the carboxyl groups of pretreated bamboo and the concentration of copper nitrate solution. More importantly, results show that the formation of carboxyl-copper (II) complex served as nucleation sites for the growth of MOF199 crystals, which was essential to prepare uniform MOF layers. The growth of MOF199 endowed bamboo with good antibacterial activity against Escherichia coli. This method provides a facile and practical strategy for designing MOF coated woody materials.