Magnetic Response Research Articles

Magnetic field-assisted enhancement of photocatalytic activity: Modified Co-POMs direct Z-scheme heterojunction Co4PW9/CeO2 for efficient carrier separation and transport

The study of photocatalysis with multi-field assistance will be a significant research direction in the future, given its capacity to effectively enhance the separation and transportation of photogenerated carriers. In this work, a new type of heterojunction photocatalyst Co4PW9/CeO2 with excellent magnetic response, which is constructed based on cobalt modified polyoxometalates (POMs) and semiconductor CeO2, was successfully prepared. Compared to the photocatalysts previously reported, the composite material Co4PW9/CeO2 developed in our study addresses the limitations associated with the recombination of photogenerated electrons and holes inherent in traditional photocatalysis systems. Numerous techniques analysis result of physicochemical characteristics of composites shows that it efficiently facilitates the separation and migration of photogenerated carriers under the influence of magnetic fields. Upon photostimulation, the oppositely directed Lorentz forces acting on the electrons and holes generated by light effectively hinder the recombination of charge carriers. Concurrently, the charge carriers accumulated at the heterojunction interface undergo rapid migration due to the application of a magnetic field, thereby leading to a substantial increase in the catalytic efficiency of the material. The experimental results of methyl orange model photodegradation demonstrated that Co4PW9/CeO2-IV exhibited superior catalytic performance. The free radical masking experiments and EPR analysis indicated that ∙O2− and ∙OH were the primary active radicals in this catalytic process. The possible photocatalytic mechanism of the heterojunction was discussed in detail. A detailed study of separation and migration behavior of photogenerated carriers when influenced by magnetic fields has been conducted, in which offering a novel perspective for enhancing photocatalytic efficiency.

Source localization comparison and combination of OPM-MEG and fMRI to detect sensorimotor cortex responses

Background and objectives:The exploration of various neuroimaging techniques have become focal points within the field of neuroscience research. Magnetoencephalography based on optically pumped magnetometers (OPM-MEG) has shown significant potential to be the next generation of functional neuroimaging with the advantages of high signal intensity and flexible sensor arrangement. In this study, we constructed a 31-channel OPM-MEG system and performed a preliminary comparison of the temporal and spatial relationship between magnetic responses measured by OPM-MEG and blood-oxygen-level-dependent signals detected by functional magnetic resonance imaging (fMRI) during a grasping task. Methods:For OPM-MEG, the β-band (15–30 Hz) oscillatory activities can be reliably detected across multiple subjects and multiple session runs. To effectively localize the inhibitory oscillatory activities, a source power-spectrum ratio-based imaging method was proposed. This approach was compared with conventional source imaging methods, such as minimum norm-type and beamformer methods, and was applied in OPM-MEG source analysis. Subsequently, the spatial and temporal responses at the source-level between OPM-MEG and fMRI were analyzed. Results:The effectiveness of the proposed method was confirmed through simulations compared to benchmark methods. Our demonstration revealed an average spatial separation of 10.57 ± 4.41 mm between the localization results of OPM-MEG and fMRI across four subjects. Furthermore, the fMRI-constrained OPM-MEG localization results indicated a more focused imaging extent. Conclusions:Taken together, the performance exhibited by OPM-MEG positions it as a potential instrument for functional surgery assessment.

Analyzing trade-off issues in synthesis of magnetic polymer compounds through theoretical investigation

Incorporating magnetic species, magnetic functional groups or additives, into polymer hosts is an effective method for synthesizing magnetic polymers. Polymers can gain magnetic moments not solely through magnetic coupling but also via the induction of Coulombic excitation. Attachment of the magnetic side-groups to the polymer backbone increases orbital localization in repeat units. This will bring two competing effects. The orbital localization will increase the intra-site Coulomb interaction, which increases magnetic moments in repeat units. Oppositely, the orbital localization also increases the energy splitting between orbitals on the polymer backbone and on side-groups, suppressing thus the magnetic moments of repeat units. However, a preference for low-spin states in the polymer units emerges when a substantial split in orbital energy occurs due to a strong coupling, consequently suppressing the magnetic moment. On the contrary, a minimal split in orbital energy within the polymer units can readily induce a high-spin state and generate a magnetic moment. However, in such cases, the Coulomb interaction triggered by the interconnected magnetic moieties might be too weak to produce a magnetic moment in the polymer. To explore this trade-off, we have proposed a theoretical two-level model aimed at elucidating the decision-making process of experimentalists during the synthesis of magnetic polymers. We also found that the dimerization of the polymer backbone together with the phonon dependence of spin–spin interaction between near-neighbor repeat units increases magnetic moments. As the magnetic responses arising from Coulombic interactions in polymers are intricately linked to carrier density, properties of the magnetic polymers acting as an active layer of a field-effect transistor can be tuned by the gate field, which controls the charge carrier density in the transistor transport channel.

Inverse spin galvanic effect in proximitized superconductor/paramagnet systems

We show that the interplay between spin–orbit coupling (SOC) and the paramagnetic response of itinerant electrons in proximitized superconductor/paramagnet systems gives rise to the inverse spin galvanic effect, i.e., generation of magnetic moment under the influence of the charge current. Depending on the sign of the SOC constant and the system temperature, the corresponding contribution to the magnetic response of the superconductor can be either diamagnetic or paramagnetic. We discuss the relevance between the discovered phenomena and the recent experiments on Pt/Nb heterostructures as well as the puzzling sign change of the magnetic response observed in clean Ag coated Nb cylinders.

Coupling pulsed magnetic treatment coated WC-12Co cemented carbide and magnetofluid to enhance milling performance of TC4 alloy

To explore an eco-friendly approach to improve the milling performance of TC4 (Ti-6Al-4 V) alloy, pulsed magnetic field treatment and magnetofluid are simultaneously applied to the NbN-coated cemented carbide (WC–12Co) milling tools. To evaluate the coupling effect of pulsed magnetic field treatment with magnetofluid, milling experiments of TC4 were conducted under cutting fluid and magnetofluid lubrication, respectively. The milling force, tool wear, and workpiece surface quality of magnetic field treated tools were compared with those of untreated tools. When the cutting fluid was lubricated, the magnetic field treatment reduced the feed force by 8.8 %. In contrast, the magnetic field treatment reduced the feed force by 20.7 % when the magnetofluid was lubricated, which reduced tool wear and also weakened coating flaking. The coupling of the magnetic field treatment and the magnetofluid significantly improved the milling performance of the tool, reducing surface roughness by 40.9 % compared to the untreated tool with cutting fluid lubrication. The enhanced milling performance mainly results from the coupling effect of magnetic field treatment and magnetofluid, which has a strong magnetic response to the treated tool and the magnetofluid was attracted to the magnetized tool, enhancing the lubrication of the contact area. In addition, the enhanced mechanical properties (8.2 % increase in hardness, 13.1 % decrease in elastic modulus, and 4.5 % increase in thermal conductivity) resulting from the pulsed magnetic field treatment reduces the milling temperature (11.7 °C) also contribute to the enhanced milling performance.

Thiol-yne click post-synthesis of phenylboronic acid-functionalized magnetic cyclodextrin microporous organic network for selective and efficient extraction of antiepileptic drugs

Owing to their incomplete digestion in the human body and inadequate removal by sewage treatment plants, antiepileptic drugs (AEDs) accumulate in water bodies, potentially affecting the exposed humans and aquatic organisms. Therefore, sensitive and reliable detection methods must be urgently developed for monitoring trace AEDs in environmental water samples. Herein, a novel phenylboronic acid-functionalized magnetic cyclodextrin microporous organic network (Fe3O4@CD-MON-PBA) was designed and synthesized via the thiol-yne click post-modification strategy for selective and efficient magnetic solid-phase extraction (MSPE) of trace AEDs from complex sample matrices through the specific B–N coordination, π-π, hydrogen bonding, electrostatic, and host-guest interactions. Fe3O4@CD-MON-PBA exhibited a large surface area (118.5 m2 g−1), rapid magnetic responsiveness (38.6 emu g−1, 15 s), good stability and reusability (at least 8 times), and abundant binding sites for AEDs. Under optimal extraction conditions, the proposed Fe3O4@CD-MON-PBA-MSPE-HPLC-UV method exhibited a wide linear range (0.5–1000 μg L−1), low limits of detection (0.1–0.5 μg L−1) and quantitation (0.3–2 μg L−1), good anti-interference ability, and large enrichment factors (92.2–104.3 to 92.3–98.0) for four typical AEDs. This work confirmed the feasibility of the thiol-yne click post-synthesis strategy for constructing novel and efficient multifunctional magnetic CD-MONs for sample pretreatment and elucidated the significance of B–N coordination between PBA and N-containing AEDs.

Amplification- and Enzyme-Free Magnetic Diagnostics Circuit for Whole-Genome Detection of SARS-CoV-2 RNA.

Polymerase chain reaction (PCR) requires thermal cycling and enzymatic reactions for sequence amplification, hampering their applications in point-of-care (POC) settings. Magnetic bioassays based on magnetic particle spectroscopy (MPS) and magnetic nanoparticles (MNPs) are isothermal, wash-free, and can be quantitative. Realizing them amplification- and enzyme-free on a benchtop device, they will become irreplaceable for POC applications. Here we demonstrate a first-in-class magnetic signal amplification circuit (MAC) that enables detection of whole genome of SARS-CoV-2 by combining the specificity of toehold-mediated DNA strand displacement with the magnetic response of MNPs to declustering processes. Using MAC, we detect the N gene of SARS-CoV-2 samples at a concentration of 104 RNA copies/μl as determined by droplet digital PCR. Further, we demonstrate that MAC can reliably distinguish between SARS-CoV-2 and other human coronaviruses. Being a wash-, amplification- and enzyme-free biosensing concept and working at isothermal conditions (25 °C) on a low-cost benchtop MPS device, our MAC biosensing concept offers several indispensable features for translating nucleic acid detection to POC applications.

Half metallic ferromagnetic and transport behavior of rare earth based CdGd2(S/Se)4 spinels

Spinel chalcogen compounds have garnered significant interest in recent ages because of their promising potential in optoelectronic and thermoelectric device applications. Here, we undertake an inclusive analysis of the structural, mechanical, electronic, magnetic, optical, and transport response of CdGd2(S/Se)4 utilizing WIEN2k code based on DFT. The determination of the crystal structure's ground state and the material's thermodynamic stability is investigated through energy vs. volume plots and ∆Hf calculation. Our analysis, including Poisson (v) and Pugh (B/G) ratios, reveals the ductile nature of the studied composition. Band gap assessments are conducted using the TB-mBJ approach, revealing the semiconducting nature of investigated compounds with direct band characteristics. Specifically, calculated band gap values are 2.2 for CdGd2S4 and 1.8 eV for CdGd2Se4. Additionally, analysis of optical properties and transport response underscores the perspective of these compositions for diverse optoelectronic and thermoelectric devices.

Magnetic hybrid micelles with controllable structures via interfacial instability-induced confined Co-assembly

Co-assembly of amphiphilic block copolymers (BCPs) and nanoparticles (NPs) is an encouraging route to produce shape-tunable functional hybrid micelles, which can integrate the excellent water stability of BCPs and the versatile functionalities of NPs. In this paper, we present an facile method to prepare magnetic hybrid micelles through confined co-assembly of polystyrene grafted Fe3O4@PS NPs and PS-b-poly(ethylene oxide) (PS-b-PEO) induced by interfacial instability of emulsion droplets. The morphology of hybrid micelles can be regulated by varying the surfactant concentration, weight fraction of Fe3O4 NPs, and block ratio of PS-b-PEO. The distribution of NPs inside the micelles is determined by the ratio (d/L) of the NP diameter (d) to the thickness of PS domain of the micelles (L). When 0.49 ≤ d/L < 0.76, the NPs locate within the cylindrical micelles. When d/L ≥ 0.76, the NPs selectively locate in the spherical micelles. More interestingly, the size-selective loading of NPs in the micelles can be achieved, even mixture of NPs different in size is applied. Moreover, these magnetic hybrid micelles show good biocompatibility and morphology-dependent magnetic resonance responsiveness, which may find potential applications in magnetic resonance imaging.

Ionic liquid functionalized magnetic polydopamine enhancing enzyme stability and catalytic efficiency for water pollutant treatment

Laccase has received widespread attention in pollutant degradation, but the current challenges in its poor stability, easy inactivation, and difficult recovery have seriously affected the application. The enzyme immobilization technology is a crucial approach to enhance the stability, recoverability, and other valuable properties to improve the effectiveness of biocatalysts. In this study, a polydopamine coating Fe3O4 nanoparticle was modified with an ionic liquid, which can be used for laccase immobilization. The incorporation of polydopamine provided a biocompatible and reactive coating for nanoparticles, while the presence of ionic liquids ensured that enzyme molecules were positioned away from the carrier surface, which facilitated the stabilization of the spatial structure of the enzyme and the retention of its activity. The immobilized laccase exhibited a broad pH and temperature and satisfactory stability. The activity of immobilized laccase remained at approximately 80 % of its activity even after incubation at 50 ℃, and over 65 % activity at storage for 30 days, which is 1.6 times and 2.9 times higher than the free laccase, respectively. The biocatalytic demonstrated excellent removal of phenolic contaminants, achieving removal efficiencies of approximately 97 % for 2,4-dichlorophenol. The remarkable magnetic response greatly facilitates the collection and subsequent reuse of the biocatalyst up to six times while still maintaining a relative removal efficiency of over 70 % for 2,4-dichlorophenol. Furthermore, the biocatalytic also exhibited excellent removal efficiency for Bisphenol A and phenol, which were 1.5 and 1.4 times more effective than the free laccase. The immobilization method provided in this work offers new ideas for the development and efficient biological enzyme preparation for industrial wastewater treatment.

Comment on: "Toward Accurate Two-Photon Absorption Spectrum Simulations: Exploring the Landscape beyond the Generalized Gradient Approximation".

A recent benchmark study of two-photon absorption (2PA) strengths using meta-generalized gradient approximation (MGGA) exchange-correlation functionals by Ahmadzadeh, Li, Rinkevicius, Norman, and Zaleśny (ALRNZ24) [ J. Phys. Chem. Lett. 2024, 15, 969] misrepresents the state of the field in this area. Not only was an assessment of 2PA strengths for the exact same benchmark published previously; ALRNZ24 also uses a gauge-variant form of MGGA response theory which produces erratic behavior for certain benchmark systems. Applications of MGGAs to optical and magnetic response properties should use a gauge-invariant extension of MGGA functionals such as paramagnetic current-dependent MGGAs.

The Recent Applications of Magnetic Nanoparticles in Biomedical Fields.

Magnetic nanoparticles (MNPs) have found extensive application in the biomedical domain due to their enhanced biocompatibility, minimal toxicity, and strong magnetic responsiveness. MNPs exhibit great potential as nanomaterials in various biomedical applications, including disease detection and cancer therapy. Typically, MNPs consist of a magnetic core surrounded by surface modification coatings, such as inorganic materials, organic molecules, and polymers, forming a nucleoshell structure that mitigates nanoparticle agglomeration and enhances targeting capabilities. Consequently, MNPs exhibit magnetic responsiveness in vivo for transportation and therapeutic effects, such as enhancing medical imaging resolution and localized heating at the site of injury. MNPs are utilized for specimen purification through targeted binding and magnetic separation in vitro, thereby optimizing efficiency and expediting the process. This review delves into the distinctive functional characteristics of MNPs as well as the diverse bioactive molecules employed in their surface coatings and their corresponding functionalities. Additionally, the advancement of MNPs in various applications is outlined. Additionally, we discuss the advancements of magnetic nanoparticles in medical imaging, disease treatment, and in vitro assays, and we anticipate the future development prospects and obstacles in this field. The objective is to furnish readers with a thorough comprehension of the recent practical utilization of MNPs in biomedical disciplines.

Facile synthesis of magnetic intelligent sensors for the pH-sensitive controlled capture of Cr(vi).

In this work, intelligent pH-sensitive sensors (Fe3O4/RhB@PAM) for Cr(vi) detection were successfully synthesized based on polyacrylamide (PAM) and Rhodamine B (RhB) co-modified Fe3O4 nanocomposites. The characterization results indicated that the sensors had many favorable properties, including suitable size, stable crystal structure and excellent magnetic response performance (47.59 emu g-1). In addition, the fluorescence changes during the detection process indicated that Fe3O4/RhB@PAM were "ON-OFF" intelligent sensors. When the Fe3O4/RhB@PAM sensors were placed in acidic Cr(vi) solution (pH 4), PAM acted as a pH-responsive "gatekeeper" releasing RhB, and the fluorescence intensity of released RhB was weakened by the complexation of Cr(vi). Furthermore, the fluorescence changes of the magnetic sensors were remarkably specific for Cr(vi) even in the presence of other competitive cations, and the limit of detection (LOD) for Cr(vi) was lower (0.347 μM) than the value recommended by the World Health Organization (0.96 μM). All the results presented in this study showed that the Fe3O4/RhB@PAM sensors had significant potential for Cr(vi) detection in acidic environmental samples.

Design of magnetic elastomer composites with tunable magnetic responses from soft to hard magnetization

Magnetic elastomer composites with tunable magnetic responses from soft to hard magnetization have been synthesized. Co-Ti co-doped barium hexaferrite (BaCoxTixFe12–2xO19) nanopowders were used as the filling and polydimethylsiloxane (PDMS) as the matrix. The effects of magnetic field-induced alignment of BaM magnetic particles in the matrix on the properties of the prepared composites have been investigated. For anisotropic magnetic elastomers, the formed chain structure plays a positive role in the enhancement of the shear energy storage modulus of the elastomers. The enhanced energy storage modulus is increased by about 190 % compared with that of the isotropic magnetic elastomers. Due to the magnetic chain structure of the magnetic particles and its effect on the rubber molecular chain, the anisotropic magnetic elastomers can obtain higher magnetic deformation response capability in the direction of the parallel magnetic field. Their research lays a foundation for further designing tunable magnetic flexible sensors.

A smart insulation material achieving self-reporting and autonomous repairing against electrical and mechanical damages based on targeted controllable microcapsules

Under the long-term action of electrical and mechanical stresses, irreversible micro-damages, such as electrical trees and cracks tend to occur inside solid insulation materials, leading to insulation failures, which have no effective countermeasures. This study develops a multi-responsive, target-controlled microcapsule to endow the epoxy resin with dual functions of self-reporting and autonomous repair against internal damage even under strong electric fields without human intervention. A turn-on mechanism for self-reporting signals is designed, to be applicable to electrical tree damage inside an epoxy matrix. In situ UV emissions generated by the partial discharge during electrical treeing are employed to automatically cure the microcapsule core material released into the damaged channel. This triggers aggregation-induced emission (AIE) signals and simultaneously repairs the damaged matrix. The polyurethane hybrid shell filled with magnetic particles endows the microcapsules with magnetic response characteristics. Under the control of a directional magnetic field, the microcapsule is concentrated around the vulnerable areas, obtaining high fluorescence emission intensity under low doping content without affecting the matrix performance. This method enables the autonomous inspection and maintenance of electric equipment and electronic devices under live working and provides new insight into the bionic intelligence of electrical and electronic insulation materials.

Synthesis and Characterization of SiO2/nGO/Fe3O4/SeQDs Nanoparticles as Potential Nanocarriers in Drug Delivery Systems.

Herein, we constructed the branch-shaped SiO2/nano GO (nGO)/Fe3O4/selenium quantum dots (QDs) (SeQDs) nanoparticles (SGF/SeQDs) embodying magnetism, fluorescence, and microwave stimulus response properties to enhance the performance of releasing drugs. The SGF/SeQDs composite was characterized by technologies including powder X-ray diffraction, transmission electron microscopy, infrared spectroscopy, etc. In the nanoparticles, the branch-shaped SiO2 provides a large specific surface area, nGO as the dielectric loss-style material promotes microwave-absorbing performance, and the Fe3O4 serves as a magnetic targeting agent and microwave absorber. Integrating nGO and Fe3O4 could further strengthen the microwave absorption of the entire composite; selenium features both fluorescence and anticancer effects. The synthesized nanoparticles as carriers exhibited a branch-like mesoporous sphere of ∼260 nm, a specific surface area of 258.57 m2 g-1, a saturation magnetization of 24.59 emu g-1, and good microwave thermal conversion performance that the temperature was elevated from 25 to 70 °C under microwave irradiation. These physical characteristics, including large pore volume (5.30 nm), high specific surface area, and fibrous morphology, are in favor of loading drugs. Meanwhile, the cumulative etoposide (VP16) loading rate of the nanoparticles reached to 21 wt % after 360 min. The noncovalent interaction between the VP16 and SGF/SeQDs was mainly the hydrogen-bonding effect during the loading process. Furthermore, the drug release rates at 180 min were up to 81.46, 61.92, and 56.84 wt % at pH 4, 5, and 7, respectively. At 25, 37, and 50 °C, the rates of drug release reach 25.40, 56.84, and 65.32 wt %, respectively. After microwave stimulation at pH 7, the rate of releasing drug increased distinctly from 56.84 to 71.74 wt % compared to that of nonmicrowave irradiation. Cytotoxicity tests manifested that the carrier had good biocompatibility. Therefore, the nanoparticles are looking forward to paving one platform for further applications in biomedicine and drug delivery systems.

Exploring the structural, morphological, and multiferroic properties of Al3+ modified (1-x) BCZT-(x) CFO ceramic composites

Multiferroics with strong magnetoelectric coupling can be created by improving the magnetostriction of the ferrite phase and combining it with the best-known piezoelectric. Herein, the ferromagnetic CoFe2O4 was modified with Al incorporation further improve the resistivity, magnetic, and magnetostrictive properties and then combined with (0.5)Ba(Zr0.2Ti0.8)O3−(0.5)(Ba0.7Ca0.3)TiO3 (BCZT) with different weight percentages. XRD results revealed the presence of a mixed spinel cubic phase for CAF (Fd-3m), whereas BCZT crystallized in a tetragonal structure (Amm2) in composite systems. The dielectric response of the materials was studied using impedance spectroscopy and it displayed a typical Maxwell–Wagner polarization of two-phase composites. The magnetic response of the CAF sample improved significantly which is attributed to the preference of Al3+ ions on tetrahedral sites. The magnetization of composites increased as the nonmagnetic BCZT component increased and the (0.75)CAF-(0.25)BCZT system had the highest saturation magnetization. We anticipate that these systems will have significantly improved magnetoelectric characteristics than unmodified CFO-BCZT systems.

Directional surface plasmon polariton scattering using single magnetic nanoparticles.

Directional surface plasmon polaritons (SPPs) are expected to promote the energy efficiency of plasmonic devices, via limiting the energy in a given spatial domain. The directional scattering of dielectric nanoparticles induced by the interference between electric and magnetic responses presents a potential candidate for directional SPPs. Magnetic nanoparticles can introduce permeability as an extra manipulation, whose directional scattered SPPs have not been investigated yet. In this work, we demonstrated the directional scattered SPPs by using single magnetic nanoparticles via simulation and experiment. By increasing the permeability and particle size, the high-order TEM modes are excited inside the particle and induce more forward directional SPPs. It indicated that the particle size manifests larger tuning range compared with the permeability. Experimentally, the maximum forward-to-backward (F-to-B) SPP scattering intensity ratio of 118.52:1 is visualized by using a single 1 μm Fe3O4 magnetic nanoparticle. The directional scattered SPPs of magnetic nanoparticles are hopeful to improve the efficiency of plasmonic devices and pave the way for plasmonic circuits on-chip.

Acoustomagnonic Spin Hall Effect in Honeycomb Antiferromagnets.

The recently discovered Van der Waals antiferromagnets have suffered from the lack of a comprehensive method to study their magnetic properties. Here, we propose an ac intrinsic magnon spin Hall current driven by surface acoustic waves as a novel probe for such antiferromagnets. Our results pave the way towards mechanical detection and manipulation of the magnetic order in two-dimensional antiferromagnets. Furthermore, they will overcome the difficulties with weak magnetic responses inherent in the use of antiferromagnets and hence provide a building block for future antiferromagnetic spintronics.

Construction of magnetic and photothermal wood membrane with asymmetric wettabilities and wind drift resistance for solar-driven seawater desalination and purification

To generate clean freshwater controllably and efficiently, Fe3O4/CNT nanomaterials and hydrophobic PVDF were introduced to delignified wood with man-made-cutting structure (D-Wood) in simple brushing method for constructing the magnetic and photothermal wood evaporator with asymmetric wettabilities and wind drift resistance. Such method could endow wood with various shapes design, outstanding magnetically sensitivity, remarkable photothermal conversion efficiency (129.08 %), high evaporation rate (1.92 kg·m−2·h−1), good dye degradability (97.23 %), and excellent wind resistance (6.6 m/s). The superhydrophilic and underwater superoleophobic bottom of Fe3O4/CNT/PVDF@D-Wood evaporator accelerated the bulk seawater transport during its evaporation procedure, but prevented the oil pollutants blocking the microchannels of evaporator during the long periods of flotation at sea. Meantime, its hydrophobic top could effectively reduce the downward diffusion of heat, and improve the salt tolerance. After 10 cycles of acid-base, ultrasound treatments and evaporating experiments, Fe3O4/CNT/PVDF@D-Wood evaporator still exhibited excellent evaporation rate and conversion efficiency, displaying remarkable repeatability and long-term durability. In weak magnetic field (3 V), its furthest response displacement and time were 5 cm and 41 s, respectively. After prolonged evaporation procedure, the magnetic responsivity of Fe3O4/CNT/PVDF@D-Wood evaporator could be in almost constant level, which offers a promising biomass product for seawater desalination and polluted-water purification.