Three-dimensional Flower-like Structure Research Articles

Three-dimensional flower-like N-doped tungsten carbide for enhanced hydrogen evolution reaction

It has been critical and challenging to develop non-precious transition-metal-based eletrocatalysts with low-cost and long-term durability for efficient water splitting. Herein, self-supported nitrogen-doped tungsten carbide on iron-nickel foam (N-WC@INF) with three-dimensional flower-like structure was prepared by a simple hydrothermal reaction followed by simultaneous nitridation and carbonization. The resulting N-WC@INF exhibits an overpotential of 103 mV at a current density of 10 mA cm−2 in alkaline media and a low Tafel slope of 47 mV dec−1, accompanied by a negligible loss of overpotential after 30 h consecutive hydrogen evolution reaction (HER). Additionally, N-WC@INF shows promising activity for oxygen evolution reaction (OER) with an overpotential of 224 mV at 10 mA cm−2 and a low Tafel slope of 22 mV dec−1.

Study on the dominant mechanism of direct hole oxidation for the photodegradation of tetracycline.

Antibiotic contamination has a significant negative impact on China, one of the largest producers and consumers of antibiotics worldwide. In this study, a three-dimensional flower-like structure of CoFe-LDHs was used to efficiently degrade tetracycline (TC) in a system triggered by peroxymonosulfate (PMS) and exposed to visible light. After exploring the effects of different metal ratios, catalyst dosage, initial TC concentrations, and pH, the optimal reaction conditions were determined. In comparison to pure CoFe-LDHs, the TC elimination rate was dramatically increased by the addition of the PMS. The strong environmental resistance, excellent stability and reusability, and universal flexibility were shown. The quenching experiments and electron spin resonance detection showed that the creation of reactive oxygen species was facilitated by the synergistic transmission of electrons between the active bimetallic components. Further, photogenerated holes was the dominant oxidizing species, which contributed more to the degradation of TC. The potential degradation pathways and intermediate toxicity of TC were suggested. This work offers a new method dominated by photogenerated holes for efficiently removing TC effluent.

Facile fabrication of BiOI/Bi2WO6 Z-scheme heterojunction composites with a three-dimensional structure for efficient degradation of pollutants

Three-dimensional BiOI/Bi2WO6 Z-scheme photocatalysts were synthesized by one-step hydrothermal method. Detailed characterization via SEM and TEM revealed that these photocatalysts exhibit a unique three-dimensional flower-like structure, composed of two-dimensional sheets. The results of photocatalysis mechanism analysis demonstrated that the BiOI/Bi2WO6 heterojunctions have formed a Z-scheme charge transfer mechanism. Specifically, electrons transfer from the Bi2WO6 conduction band to the BiOI valence band, facilitating both enhanced separation of photogenerated charges and the preservation of the strong reducibility of BiOI conduction band electrons and the strong oxidation of Bi2WO6 valence band holes. This dual effect leads to increased generation of free radicals and a consequent improvement in photocatalytic property. Remarkably, when the molar ratio of BiOI/Bi2WO6 is set at 40%, the first-order reaction rate constant reaches 0.089 min−1, which is nearly 5.9 times that of pure Bi2WO6.

Flower-like In2O3-ZnO nanosensor with improved acetone performance at low temperature

In2O3-ZnO nanoflower-like acetone gas sensors with varied reaction time were created using a simple and green synthesis idea. Morphological and structural analysis indicated that the In2O3-ZnO nanoflowers were made up of nanoplates with a thickness of around 35–60 nm and some small nanoparticles with the particle size of about 11 nm adhered to the surface. With a sensitivity of 238 for 100 ppm acetone at 140 °C, a lower detection limit as low as 0.64 ppm, good selectivity and excellent stability, the In-Zn(5) sensor with a hydrothermal time of 5 h has the most excellent performance. The enhanced gas-sensitive performance of In-Zn(5) can be attributed to the heterogeneous structure between the two and the three-dimensional flower-like structure with a large specific surface area and fast gas transfer rate. This work brings a better prospect for the future detection of acetone.

Synthesis of Graphene Oxide-Coupled CoNi Bimetallic MOF Nanocomposites for the Simultaneous Analysis of Catechol and Hydroquinone.

Herein, a three-dimensional flower-like cobalt-nickel bimetallic metal-organic framework (CoNi-MOF) coupled with two-dimensional graphene oxide (GO) nanocomposites was successfully synthesized for the selective and simultaneous electrochemical determination of catechol (CC) and hydroquinone (HQ). The three-dimensional flower-like structure of the CoNi-MOF/GO nanocomposite has a multilayer structure and a large surface area, which greatly improves its electrocatalytic activity towards CC and HQ. Differential pulse voltammetry (DPV) results showed that the peak-to-peak separation of CC (0.223 V) and HQ (0.120 V) was 103 mV at a CoNi-MOF/GO modified glassy carbon electrode (CoNi-MOF/GO/GCE), suggesting that the proposed modified electrode can selectively and simultaneously determine them. Under optimal conditions, the CoNi-MOF/GO/GCE showed an excellent analytical performance for the simultaneous determination of CC and HQ, including a wide linear range (0.1-100 μM), low detection limit (0.04 μM for HQ and 0.03 μM for CC) and high anti-interference ability. As expected, the developed modified electrode has been used to analyze CC and HQ in river water, with acceptable results.

Photocatalytic degradation performance of antibiotics by peanut shell biochar anchored NiCr-LDH nanocomposites fabricated by one-pot hydrothermal protocol

The development of carbon-based mesoporous semiconductor composites with superior photocatalytic performance is of great importance for water remediation of organic pollution caused by antibiotics or dyes. In this work, series of novel peanut shell biochar anchored NiCr-LDH(NiCr-LDH/PSB) photocatalysts were constructed via one-pot hydrothermal method for photodegradation of ofloxacin and tetracycline antibiotics. The comprehensive characterization indicated that NiCr-LDH uniformly dispersed on biochar matrix and formed a three-dimensional flower-like mesoporous structure. Appropriate doping of PSB can remarkably improve the photodegradation performance of NiCr-LDH for ofloxacin and tetracycline removal under UV-light irradiation. The photodegradation efficiency is better than that of pristine NiCr-LDH and biochar alone. More importantly, the optimal NiCr-LDH/PSB (18 %) composite exhibited the superior photodegradation and mineralization performance for ofloxacin and tetracycline. The photocatalytic degradation activities of NiCr-LDH/PSB for OFX and TC were about 3.5 and 2.3 times than that of NiCr-LDH, respectively. After four successive operations, the removal efficiency decreased by less than 20 %, suggesting that the as-synthesized NiCr-LDH/PSB has a good application prospect. Furthermore, a possible photocatalytic mechanism with •OH and •O2− as the main active species was proposed on the basis of photoelectrical properties, active species trapping and ESR tests. The study offers a novel idea for the fabrication of biochar anchored LDH system with excellent synergic adsorption and photocatalytic performance for the removal of antibiotic wastewater.

Improvement of Interfacial Properties and Bioactivity of CF/PEEK Composites by Rapid Biomineralization of Hydroxyapatite.

The carbon fiber/hydroxyapatite (CF/HA) reinforcement with a three-dimensional flower-like structure was rapidly fabricated with the biomimetic mineralization method to strengthen the interfacial performance and bioactivity of carbon fiber/polyether ether ketone (CF/PEEK) composites. Silk fibroin (SF), which can construct a robust interphase between CF and PEEK, supported an organic template to regulate the growth of inorganic HA. The interfacial properties were markedly enhanced through mechanical interlocking and interface adhesion induced by increasing roughness and surface energy of CF. Besides, the mineralization time was significantly reduced after the addition of cetyltrimethylammonium bromide to the simulated body fluid, and the prepared CF/HA possessed good bioactivity. In this study, the interlaminar shear strength (ILSS) and flexural strength of CF-HA/45/PEEK composites demonstrated an enhancement of 45.9% and 51.2%, respectively, compared to the untreated CF/PEEK composites. It is predicted that this strategy could provide a rapid and convenient route to ameliorate the interfacial performance and bioactivity of CF/PEEK composites simultaneously.

Superior photocatalytic performance of a novel flower-like Bi24Si2O40-Bi2O2SiO3 composite via organic-guided crystal growth and bandgap regulation

Aurivillius oxide layered materials are formed by bismuth oxide and pseu-do-perovskite layers, which usually presents a mica-like lamellar structure, that is easy to stack with each other, affecting the exposure of active sites, thereby reducing its photocatalytic performance. Herein, the organic modifier is used to adjust the morphology to obtain Bi24Si2O40-Bi2O2SiO3 (BSO) with three-dimensional flower-like structure. Furthermore, the optimization of morphology promotes the effective formation of heterostructures, organic-mediated morphology growth and the regulation of heterojunction effectively improves the activity of superoxide radicals (•O2−) and holes (h+). Therefore, the organic-modified MBSO-2 shows excellent photocatalytic performance, and its degradation rates of rhodamine B (RhB), ciprofloxacin (CIP) and norfloxacin (NOR) can reach 98.7%, 87.4% and 89.0%, respectively. Moreover, the great improvement of the degradation of RhB and NOR by MBSO-2 can be attributed to the important role played by its active species (h+ and •O2−), which shows that it is more conducive to improving the degradation of pollutants with h+ and •O2− as the degradation path. The modification strategy of organic-mediated lamellar growth provides a new idea for the morphology control of layered metal oxide photocatalysts and broadens its application.

Improvement of photocatalytic activity of BiOBr and BiOBr/ZnO under visible-light irradiation by short-time low temperature plasma treatment

In this work, BiOBr and BiOBr/ZnO were produced by using a simple hydrothermal method, and then were modified by a short-time low temperature plasma treatment using the gas of argon mixed with 3% hydrogen in pulsed mode with the fixed cycle discharge times. The related morphological, crystal, chemical, optical and photocatalytic properties were investigated. A three-dimensional flower-like structure of pure BiOBr and layered ultrathin nanosheets structure of BiOBr/ZnO can be observed. And the plasma treatment process at the discharge power of 100 W would not affect their basic morphologies. However, the changes in the surface chemical bonding has been identified, which indicates the presence of strong electronic interactions and strong chemical bonds caused by the plasma modification. The photodegradation rate has been greatly improved by mixing BiOBr with ZnO since the heterojunction structure was built during the hydrothermal process. Moreover, the photocatalytic activity can be further improved after the plasma treatment, it is attributed to the higher photogenerated carrier separation rate and narrow band gap due to the defects generated by the surface plasma effects.

Ag doped Co/Ni bimetallic organic framework for determination of luteolin

Electrochemical determination of luteolin is vital to food industry owing to its bioactive properties such as anti-viral, anti-ulcer. However, bare electrode of traditional electrochemical sensors generally have narrow linear range and low sensitivity, which sets limit on their practical application. Accordingly, a new nano-architecture fabricated with Ag doped CoNi-bimetal metal–organic frameworks (Ag-CoNi-MOF) is developed as a material for electrochemical determination of luteolin. The introduction of Ag to three-dimensional (3D) flower-like hierarchical structure greatly increases specific surface area and electrical conductivity, which subsequently provides more excellent active sites for luteolin oxidation. Under optimal conditions, Ag-CoNi-MOF sensor presents a broader linear response to luteolin concentration of 0.002 – 1.0 μM with the detection limit as low as 0.4 nM (S/N = 3). Ag-CoNi-MOF has good anti-interference according to compared amperometric current response of luteolin within different organic analytes and metal ions. Finally, the sensor platform is implemented directly to determine luteolin in human urine for evaluation of its practical application. In general, Ag-CoNi-MOF sensors fabricated perform larger linear range with high sensitivity and anti-interference properties, which can be used as a potential material for electrochemical determination of luteolin.

High-Stability Ti3C2-QDs/ZnIn2S4/Ti(IV) Flower-like Heterojunction for Boosted Photocatalytic Hydrogen Evolution.

The practical application of photocatalytic H2-evolution is greatly limited by its sluggish charge separation, insufficient active sites, and stability of photocatalysts. Zero-dimensional (0D) Ti3C2 MXene quantum dots (MQDs) and amorphous Ti(IV) have been proven to be potential substitutes for noble co-catalyst to accelerate the separation of photogenerated electron-hole pairs and prevent the self-oxidation of photocatalysts, leading to better photocatalytic H2-evolution performance with long-term stability. In this study, amorphous Ti(IV) and MQDs co-catalysts were successfully deposited on ZnIn2S4 (ZIS) microspheres composed of ultra-thin nanosheets via a simple impregnation and self-assembly method (denoted as MQDs/ZIS/Ti(IV)). As expected, the optimal MQDs/ZIS/Ti(IV) sample exhibited a photocatalytic H2-evolution rate of 7.52 mmol·g−1·h−1 and excellent photostability without metallic Pt as the co-catalyst in the presence of Na2S/Na2SO3 as hole scavenger, about 16, 4.02 and 4.25 times higher than those of ZIS, ZIS/Ti(IV), and MQDs/ZIS, respectively. The significantly enhanced photocatalytic H2-evolution activity is attributed to the synergistic effect of the three-dimensional (3D) flower-like microsphere structure, the amorphous Ti(IV) hole co-catalyst, and a Schottky junction formed at the ZIS–MQDs interface, which offers more active sites, suppresses self-photocorrosion, and photo-generates the charge recombination of ZIS.

Three-dimensional Prussian blue nanoflower as a high-performance sodium storage electrode for water desalination

Capacitive deionization (CDI) is considered as a potential water treatment technology to answer the dilemma of fresh water shortage. Currently, many efforts have been exerted to make intercalation material a promising candidate for CDI in order to realize the commercial feasibility. Herein, we report a facile strategy to prepare three-dimensional flowerlike Prussian blue (PB) intercalation material for efficient water desalination. The PB nucleus achieves oriented growth to form a unique six-petal flowerlike structure because of the addition of ethanol. Compared with cubic PB, flowerlike PB with superior inherent properties has more advantages in desalination capacity and cycling stability. The rocking chair desalination cell assembled by symmetrical electrodes of flowerlike PB delivers a high desalination capacity of 101.3 mg/g and maintains more than 93% of the initial capacity after 60 cycles. The enhanced capacity can be attributed to the three-dimensional flowerlike structure of flowerlike PB, which can enlarge the contact area between electrode and electrolyte, improve the delivery and conversion of Na+ ion. Furthermore, the unique flowerlike structure provides sufficient buffer space for crystal deformation, thus enhancing the stability. Therefore, this work proves flowerlike PB is a promising intercalation material for CDI and paves the way for its application in other fields of electrochemistry.

Hydrothermal synthesis of Co3O4 nanoparticles decorated three dimensional MoS2 nanoflower for exceptionally stable supercapacitor electrode with improved capacitive performance

In this study, a novel, Co3O4 nanoparticle decorated MoS2 nanoflower (MoS2/Co3O4) has been fabricated via a facile hydrothermal method by taking different concentrations of Co3O4 (0, 1, 2, 4, and 6%). The FE-SEM images represent a three-dimensional flower-like structure for MoS2 and MoS2/Co3O4. The different structural parameters of the nanoflowers were estimated from the XRD analysis. TEM analysis revealed that the inter-planar spacing of the nanostructure varied with the concentration of the Co3O4 nanoparticles. The Raman spectroscopy of MoS2/Co3O4 nanoflower showed a distinct low-shift of the first-order Raman peaks suggesting n-type doping due to the incorporation of Co3O4. The specific capacitance as high as 220.72 mFcm-2 at 0.14 mAcm-2 together with high energy density and superior cycling stability (87% capacitance retention after 10,000 charge/discharge cycles) were obtained for the MoS2/Co3O4 (4%) nanocomposite from the electrochemical analysis. This improved specific capacitance of MoS2/Co3O4 can be attributed to the higher surface area, defect-rich structure, and lower charge transfer resistance of the prepared sample. The MoS2/Co3O4 nanostructure with improved specific capacitance and higher stability synthesized from a simple, low-cost process will pave the way to the production of efficient and economic energy storage devices.

Facile Preparation of Nickel Hydroxide Composite Material as Highly Efficient Electrocatalyst for Oxygen Evolution Reaction

With the development of industry, the large-scale consumption of fossil energy has brought serious environmental pollution. Therefore, the development of renewable clean energy to replace traditional fossil fuels has become the focus of research. In this study, nickel hydroxide (Ni(OH)2) composite was prepared by a simple hydrothermal method. Transmission electron microscope (TEM), scanning electron microscope (SEM) and X-ray diffraction (XRD) were used to characterize its morphology and structure. The results proved the successful preparation of the Ni(OH)2 composite and show that the prepared composite has a three-dimensional flower-like structure. In addition, the electrochemical performance of the prepared Ni(OH)2 composite was investigated under the three-electrode system. The three-dimensional flower-like structure of the composite can make the electrode and electrolyte fully contact, providing a rapid transfer path for ions and electrons to improve the electrochemical performance of the electrode material. This work provides new ideas for the preparation of self-assembled nickel-based materials and the wide application in electrocatalyst.

Bifunctional three-dimensional self-supporting multistage structure CC@MOF-74(NiO)@NiCo LDH electrode for supercapacitors and non-enzymatic glucose sensors

The bifunctional electrode materials for supercapacitors and non-enzymatic glucose sensors have attracted the researchers’ great interest due to their excellent electrochemical performance. In this work, three-dimensional self-supporting multistage structure CC@MOF-74(NiO)@NiCo LDH electrode has been successfully prepared through a facile hydrothermal and electrochemical deposition method. Benefiting from the unique three-dimensional flower-like multistage structure, the optimized CC@MOF-74(NiO)@NiCo LDH electrode exhibits an excellent specific capacitance of 9.73 F cm−2 and a superior rate capability of 77.65% at a high current density of 50 mA cm−2. Besides, the material has a superior capacitance retention rate of 84.09% after 5000 cycles. Furthermore, the fabricated CC@MOF-74(NiO)@NiCo LDH//CC@NiCo2O4 @NiFe LDH ASC device exhibits a high energy density of 22.85 Wh kg−1 and the power density of 1750 W kg−1 at the current density of 10 mA cm−2. Moreover, the as-prepared CC@MOF-74(NiO)@NiCo LDH shows an outstanding electrocatalytic performance in glucose detection, including a high sensitivity of 1699 μA mM−1 cm−2, a low detection limit of 278 nM (S/N = 3) and a wide linear range of 10 μM–1.1 mM and 1.5–9 mM. The electrode also has good long-term stability and remains 93.29% of the original current density after 35 days. The unique three-dimensional flower-like structure of MOF-74 and two-dimensional layered double hydroxides (LDHs) nanosheets structure provide a larger specific surface area and improve the conductivity of the MOF-74(NiO). Furthermore, the synergistic effect of the bimetal Ni-Co provides more active sites for electrochemical reactions and shortens the ion transport path. Accordingly, the fabricated CC@MOF-74(NiO)@NiCo LDH has great potential application prospects in the field of supercapacitors and non-enzymatic glucose sensors.

Novel morphology-controlled three-dimensional flower-like magnetic CoFe2O4/CoFe-LDHs microsphere for high efficient removal of Orange II

• Novel flower-like magnetic CoFe 2 O 4 /CoFe-LDHs microspheres have been fabricated. • The existence of SO 4 2- and reaction time can influence the formation of structure of composites. • CoFe 2 O 4 /CoFe-LDHs exhibit remarkable adsorption performance of 1940 mg g −1 towards Orange II . • Adsorption mechanism includes anion exchange, hydrogen bonding, coordination and surface adsorption. Novel three-dimensional flower-like magnetic CoFe 2 O 4 /CoFe-LDHs microspheres were fabricated via a facile one-step hydrothermal method without any other operation. CoFe 2 O 4 /CoFe-LDHs microspheres could possess strong magnetic performance directly without calcination procedure. By controlling reaction time and anion type of raw materials, three-dimensional flower-like structure microspheres could be obtained. Then the structural and surface properties of the prepared CoFe 2 O 4 /CoFe-LDHs were investigated by a comprehensive set of characterization techniques closely. Besides, as-prepared composites exhibited remarkable adsorption performance towards Orange II and the maximum adsorption capacity could be high to 1940 mg·g −1 , several times higher than the adsorption capacity of other adsorbents reported and amorphous CoFe 2 O 4 /CoFe-LDHs prepared in this work, proving three dimensional porous structures could contribute to higher adsorption performance. Moreover, batch experiments were conducted systematically to evaluate the effects of the initial concentration of Orange II, pH, temperature and time on the adsorption behavior of Orange II on CoFe 2 O 4 /CoFe-LDHs. The adsorption kinetics and isotherm studies indicated adsorption progress obeyed the pseudo-second-order and Langmuir model respectively. Formation mechanism and adsorption mechanism were both studied deeply. What’s more, adsorbents and sample solution could be separated from each other quickly by an external magnet. These results suggested CoFe 2 O 4 /CoFe-LDHs composite was an effective and promising adsorbent for the removal of dye pollutants.

Double-template-regulated bionic mineralization for the preparation of flower-like BiOBr/carbon foam/PVP composite with enhanced stability and visible-light-driven catalytic activity

A novel flower-like BiOBr/carbon foam (CF)/polyvinylpyrrolidone (PVP) composite with a narrow bandgap was fabricated by double-template-regulated bionic mineralization using CF as a hard template and PVP as a soft template. The structure, morphology, and optical properties of the BiOBr/CF/PVP composite were systematically characterized. The photocatalytic activity of the samples was investigated based on the catalytic degradation efficiency of rhodamine B (RhB). The results indicated that the photocatalytic performance of the BiOBr/CF/PVP composite with an optimal mineralization time of 10h was superior to those of BiOBr/CF, BiOBr/PVP, and pure BiOBr. The enhanced activity of the BiOBr/CF/PVP composite could be attributed to the good hydrophilic properties, unique three-dimensional flower-like structure, improved visible-light absorption, effective separation of photogenerated electron-hole pairs, and an increase in (110)/(102) crystal plane ratio of BiOBr. In addition, the possible degradation pathways of RhB photocatalyzed by BiOBr/CF/PVP were analyzed by tracking the degradation by-products. After consecutive degradation reactions, the catalytic performance and structure of BiOBr/CF/PVP exhibited no remarkable changes. Notably, the BiOBr/CF/PVP composite exhibited good reusability, excellent stability, and high adsorption-photocatalytic properties and could be easily separated from the reaction system for recycling.

Enhanced photocatalytic performance of three-dimensional microstructure Bi2SiO5 by ionic liquid assisted hydrothermal synthesis

In this demonstration, Bi2SiO5 photocatalysts were prepared using ionic liquid (IL) 1-butyl-3-methylimidazolium tetrafluoroborate ([BMim]BF4) as a soft template. X-ray diffraction (XRD), high resolution transmission electron microscopy (HRTEM), X-ray photoelectron spectroscopy (XPS), UV–Vis diffuse reflectance spectroscopy (UV–Vis DRS), surface photovoltage spectroscopy (SPS), electron paramagnetic resonance (EPR), photoelectrochemical measurement and Raman were applied to investigate the structures, morphologies, optical and electronic properties. The results show that [BMim]BF4 affects the growth of IL-Bi2SiO5 grains and induces Bi2SiO5 to form thinner nanosheets. When the mass ratio of [BMim]BF4/Bi2SiO5 is 3%, Bi2SiO5 nanosheets begin to assemble into three-dimensional (3-D) flower-like structure. Rhodamine B (RhB) was employed to evaluate the photocatalytic performance of IL- Bi2SiO5. Under UV light irradiation, the degradation rate constant of RhB over the 3% sample is 5 times of that over the reference Bi2SiO5.

Magnetically Driven 3D Cellulose Film for Improved Energy Efficiency in Solar Evaporation.

The architecture of cellulose nanomaterials is definitized by random deposition and cannot change in response to shifting application requirements. Herein, we present a magnetic field-controlled cellulose film derived from wood that exhibits great magnetic properties and reliable tunability enabled by incorporated Fe3O4 nanoparticles and cellulose nanofibers (CNF) with a large length-diameter ratio. Fe3O4 nanoparticles are dispersed in suspensions of CNF so as to enhance the magnetic response. The plane magnetic CNF can be processed to form a three-dimensional (3D) flower-like structure along the magnetic induction line after applying an external magnet. Inspired by the fluidic transport in natural flowers, a bilayer structure was created using the 3D flower-like film as the solar energy receiver and natural wood as the water pathway in a solar-derived evaporation system. Compared with a planar cellulose film decorated with Fe3O4, the 3D structure design can greatly improve the evaporation rate from 1.19 to 1.39 kg m-2 h-1 and the efficiency from 76.9 to 90.6% under 1 sun. Finite element molding further reveals that the 3D structural top layer is beneficial for the formation of a gradient temperature profile and the improvement of the energy efficiency through the reduction of thermal radiation. The magnetically controlled fabrication represents a promising strategy for designing cellulose nanomaterials with a complicated structure and controllable topography, which has a wide spectrum of applications in energy storage devices and water treatment.

3D flower-liked Fe3O4/C for highly sensitive magnetic dispersive solid-phase extraction of four trace non-steroidal anti-inflammatory drugs.

A low cost-effective and simple synthesis method was adopted to acquire three-dimensional flower-like structure Fe3O4/C that has large specific area, suitable pore structure and sufficient saturation magnetism. The obtained Fe3O4/C exhibits outstanding preconcentration ability andwas applied to extracting non-steroidal anti-inflammatory drugs from complex environmental and biological samples. The parameters of magnetic solid-phase extraction were optimized by univariate and multivariate methods (Box-Behnken design). The high degree of linearity from 2.5 to 1000.0ngmL-1 (R2≥ 0.9976), the limits of detection from 0.25 to 0.5ngmL- 1 (S/N= 3), and the limits of quantitation from 1.0 to 2.0ngmL- 1 (S/N= 10) were yielded by adopting this novel method after the optimization. Moreover, the recoveries of non-steroidal anti-inflammatory drugs from 89.6 to 107.0% were acquired in spiked plasma, urine and lake samples. In addition, the adsorption of non-steroidal anti-inflammatory drugs on Fe3O4/C was explored by adsorption isotherms and kinetic studies. Furthermore, the adsorption mechanism for non-steroidal anti-inflammatory drugs by Fe3O4/C was proposed, which was hydrogen bonding and π-π interaction between non-steroidal anti-inflammatory drugs and Fe3O4/C. Graphical abstract.