1
|
Elbaz Y, Caspary Toroker M. From density functional theory to machine learning predictive models for electrical properties of spinel oxides. Sci Rep 2024; 14:12150. [PMID: 38802595 DOI: 10.1038/s41598-024-62788-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/05/2024] [Accepted: 05/17/2024] [Indexed: 05/29/2024] Open
Abstract
This work focuses on predicting and characterizing the electronic conductivity of spinel oxides, which are promising materials for energy storage devices and for the oxygen evolution and oxygen reduction reactions due to their attractive properties and abundance of transition metals that can act as active sites for catalysis. To this end, a new database was developed from first principles, including band structure and conductivity properties of spinel oxides, and machine learning algorithms were trained on this database to predict electronic conductivity and band gaps based solely on the compositions. The models developed in this study are scaled from the quantum level up to a continuum conductivity model. The relatively small database used in this study allowed for accurate predictions of band gap and conductivity. By altering the composition of spinel oxides, the model was able to predict high conductivity for spinels with high nickel content and to match experimental trends for manganese cobalt spinels. The ability to predict material properties is especially important in energy conversion devices such as batteries and supercapacitors where redox reactions take place.
Collapse
Affiliation(s)
- Yuval Elbaz
- Department of Materials Science and Engineering, Technion - Israel Institute of Technology, 3600003, Haifa, Israel
| | - Maytal Caspary Toroker
- Department of Materials Science and Engineering, Technion - Israel Institute of Technology, 3600003, Haifa, Israel.
- The Nancy and Stephen Grand Technion Energy Program, Technion - Israel Institute of Technology, 3600003, Haifa, Israel.
| |
Collapse
|
2
|
Kiejna A, Kruk K, Ossowski T. Structural, electronic and magnetic properties of greigite Fe 3S 4by GGA and GGA+ Uversus SCAN meta-GGA density functionals. JOURNAL OF PHYSICS. CONDENSED MATTER : AN INSTITUTE OF PHYSICS JOURNAL 2023; 36:135601. [PMID: 38096592 DOI: 10.1088/1361-648x/ad15c8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/22/2023] [Accepted: 12/14/2023] [Indexed: 12/28/2023]
Abstract
The performance of exchange-correlation functional of density functional theory represented in generalized gradient approximation (GGA) and in the strongly constrained and appropriately normed (SCAN) meta-GGA scheme to study structural, electronic, and magnetic properties of greigite (Fe3S4) was investigated. The effects of inclusion of strong electron correlations represented by on-site Hubbard correctionU, and nonlocality of the long-range van der Waals (vdW) interactions were also considered. Geometry optimization yielded the inverse spinel structure and lattice parameter of greigite in good agreement with experimental data. Calculated electronic structure revealed a half-metallic nature of the greigite bands for the applied functionals except for GGA, which predicts metallic behavior. Antiferromagnetic coupling of iron ions in tetrahedral and octahedral coordinations makes the overall crystal structure ferrimagnetic. In general the GGA+Uand SCAN show comparable performance in prediction physical properties of greigite. Inclusion of the vdW correction does not change the character of the bands.
Collapse
Affiliation(s)
- Adam Kiejna
- Institute of Experimental Physics, University of Wrocław, Plac M. Borna 9, 50-204 Wrocław, Poland
| | - Karolina Kruk
- Institute of Experimental Physics, University of Wrocław, Plac M. Borna 9, 50-204 Wrocław, Poland
| | - Tomasz Ossowski
- Institute of Experimental Physics, University of Wrocław, Plac M. Borna 9, 50-204 Wrocław, Poland
| |
Collapse
|
3
|
Naveas N, Pulido R, Marini C, Gargiani P, Hernandez-Montelongo J, Brito I, Manso-Silván M. First-Principles Calculations of Magnetite (Fe 3O 4) above the Verwey Temperature by Using Self-Consistent DFT + U + V. J Chem Theory Comput 2023; 19:8610-8623. [PMID: 37974305 PMCID: PMC10720343 DOI: 10.1021/acs.jctc.3c00860] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/07/2023] [Revised: 10/10/2023] [Accepted: 10/30/2023] [Indexed: 11/19/2023]
Abstract
In this report, we have used the DFT + U + V approach, an extension of the DFT + U approach that takes into account both on-site and intersite interactions, to simulate structural, magnetic, and electronic properties together with the Fe and O K-edge XAS spectra of Fe3O4 above the Verwey temperature (Tv). Moreover, we compared the simulated XAS spectra with experimental XAS data. We examined both orthogonalized and nonorthogonalized atomic orbital projectors and compared DFT + U + V to DFT, DFT + U, and HSE as a hybrid functional. It is noteworthy that, despite the widespread use of the same Hubbard U value for Feoct and Fetet at the DFT + U level in the literature, the HP code identified two distinct values for them using the Hubbard approaches (DFT + U and DFT + U + V). The resulting Hubbard U and V parameters are strongly dependent on the chosen orbital projectors. This study demonstrates how DFT + U + V can improve the structural, magnetic, and electronic properties of Fe3O4 compared to approximate DFT and DFT + U. In this context, DFT + U + V supports the half-metallic character of the bulk crystal Fe3O4 above Tv, since the Fermi level is found in the t2g band with a Feoct down-spin. Thus, the observations in the current study emphasize the significance of intersite interactions in the theoretical analysis of Fe3O4 above the Tv.
Collapse
Affiliation(s)
- Nelson Naveas
- Departamento
de Física Aplicada, Universidad Autónoma
de Madrid, 28049 Madrid, Spain
- Departamento
de Ingeniería Química y Procesos de Minerales, Universidad de Antofagasta, Avenida Angamos 601, 1270300 Antofagasta, Chile
- Instituto
Universitario de Ciencia de Materiales “Nicolás Cabrera”
(INC), Universidad Autónoma de Madrid, Campus de Cantoblanco, 28049 Madrid, Spain
| | - Ruth Pulido
- Instituto
Universitario de Ciencia de Materiales “Nicolás Cabrera”
(INC), Universidad Autónoma de Madrid, Campus de Cantoblanco, 28049 Madrid, Spain
- Departamento
de Química, Universidad de Antofagasta, Avenida Angamos 601, 1270300 Antofagasta, Chile
| | - Carlo Marini
- CELLS−ALBA
Synchrotron, 08290 Cerdanyola del Valles, Spain
| | | | | | - Ivan Brito
- Departamento
de Química, Universidad de Antofagasta, Avenida Angamos 601, 1270300 Antofagasta, Chile
| | - Miguel Manso-Silván
- Departamento
de Física Aplicada, Universidad Autónoma
de Madrid, 28049 Madrid, Spain
- Instituto
Universitario de Ciencia de Materiales “Nicolás Cabrera”
(INC), Universidad Autónoma de Madrid, Campus de Cantoblanco, 28049 Madrid, Spain
- Centro
de Microanálisis de Materiales, Universidad
Autónoma de Madrid, Campus de Cantoblanco, 28049 Madrid, Spain
| |
Collapse
|
4
|
Ren Y, Li Y, Xu N, Guo K, Xu Z, Chen X, Liu H, Gao J. Regulation of saturation magnetization of magnetite by doping with group III elements. Phys Chem Chem Phys 2023. [PMID: 38047897 DOI: 10.1039/d3cp03789d] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/05/2023]
Abstract
Magnetic Fe3O4 nanoparticles show promising applications in nanomedicine. However, the saturation magnetization (MS) of Fe3O4 nanoparticles synthesized in laboratory is usually not high enough, which greatly limits their application in drug delivery and magnetic hyperthermia. Here, by accurate hybrid density functional computation, the doping behavior of group III elements (including Al, Ga, and In) and the effects on magnetic and electronic properties are well studied. The results show that the doping behavior depends on the concentration of dopants. Interestingly, appropriate Ga and In doping concentrations can significantly increase the MS of Fe3O4. In addition, the doping of group III elements (Al, Ga and In) into Fe3O4 would not induce any defect states in the band gap but slightly increases the band gap. Our results provide a simple and feasible scheme for increasing the MS of magnetite, which is significant for the applications of Fe3O4 nanoparticles in drug delivery and magnetic hyperthermia.
Collapse
Affiliation(s)
- Yanying Ren
- The Second Hospital of Dalian Medical University, Dalian 116024, China.
| | - Yaning Li
- Department of Physics, Dalian University of Technology, Dalian 116024, China.
| | - Nan Xu
- The Second Hospital of Dalian Medical University, Dalian 116024, China.
| | - Kun Guo
- The Second Hospital of Dalian Medical University, Dalian 116024, China.
| | - Zhaohui Xu
- The Second Hospital of Dalian Medical University, Dalian 116024, China.
| | - Xin Chen
- The Second Hospital of Dalian Medical University, Dalian 116024, China.
| | - Hongsheng Liu
- Department of Physics, Dalian University of Technology, Dalian 116024, China.
| | - Jufeng Gao
- Department of Physics, Dalian University of Technology, Dalian 116024, China.
| |
Collapse
|
5
|
Garg P, Mohapatra L, Poonia AK, Kushwaha AK, Adarsh KNVD, Deshpande U. Single Crystalline α-Fe 2O 3 Nanosheets with Improved PEC Performance for Water Splitting. ACS OMEGA 2023; 8:38607-38618. [PMID: 37867698 PMCID: PMC10586280 DOI: 10.1021/acsomega.3c05726] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 08/04/2023] [Accepted: 09/22/2023] [Indexed: 10/24/2023]
Abstract
We report the photoelectrochemical (PEC) performance of a densely grown single crystalline hematite (α-Fe2O3) nanosheet photoanode for water splitting. Unlike expensive ITO/FTO substrates, the sheets were grown on a piece of pure Fe through controlled thermal oxidation, which is a facile low cost and one-step synthesis route. The sheets grow with a widest surface parallel to basal plane (0001). Iron oxide formed on Fe consisting of layer structure α-Fe2O3-Fe3O4-Fe is elucidated from GIXRD and correlated to spectral features observed in Raman and UV-vis spectroscopy. The top α-Fe2O3 nanosheet layer serves as a photoanode, whereas the conducting Fe3O4 layer serves to transport photogenerated electrons to the counter electrode through its back contact. Time-resolved photoluminescence (TRPL) measurements revealed significantly prolonged carrier lifetime compared to that of bulk. Compared to the thin film of α-Fe2O3 grown on the FTO substrate, ∼3 times higher photocurrent density (0.33 mA cm-2 at 1.23 VRHE) was achieved in the nanosheet sample under solar simulated AM 1.5 G illumination. The sample shows a bandgap of 2.1 eV and n-type conductivity with carrier density 9.59 × 1017 cm-3. Electrochemical impedance spectroscopy (EIS) measurements reveal enhanced charge transport properties. The results suggest that nanosheets synthesized by the simple method yield far better PEC performance than the thin film on the FTO substrate. The anodic shifts of flat band potential, delayed electron-hole recombination, and growth direction parallel to the highly conducting basal plane (0001) being some of the contributing factors to the higher photocurrent observed in the NS photoanode are discussed. Characterizations carried out before and after the PEC reaction show excellent stability of the nanosheets in an alkaline electrochemical environment.
Collapse
Affiliation(s)
- Parveen Garg
- UGC-DAE
Consortium for Scientific Research, University Campus, Khandwa Road, Indore 452001, Madhya Pradesh, India
| | - Lokanath Mohapatra
- Department
of Metallurgical Engineering and Materials Science, Indian Institute of Technology Indore, Simrol, Indore 453552, India
| | - Ajay Kumar Poonia
- Department
of Physics, Indian Institute of Science
Education and Research Bhopal, Bhopal 462066, India
| | - Ajay Kumar Kushwaha
- Department
of Metallurgical Engineering and Materials Science, Indian Institute of Technology Indore, Simrol, Indore 453552, India
| | | | - Uday Deshpande
- UGC-DAE
Consortium for Scientific Research, University Campus, Khandwa Road, Indore 452001, Madhya Pradesh, India
| |
Collapse
|
6
|
Afify AA, Abd El-Fattah ZM, Esmail MSM, El-Bahnasawy HH. Comparative Mössbauer and first principles calculations for selected iron oxides and ferrites nanoparticles. MATERIALS TODAY COMMUNICATIONS 2023; 35:106193. [DOI: 10.1016/j.mtcomm.2023.106193] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 09/02/2023]
|
7
|
Choi Y, Lee WS, Lee J, Park SH, Kim S, Kim KH, Park S, Kim EH, Kim JK. Capacitive Electrode-Based Electric Field Treatments on Redox-Toxic Iron Deposits in Transgenic AD Mouse Models: The Electroceutical Targeting of Alzheimer's Disease Feasibility Study. Int J Mol Sci 2023; 24:ijms24119552. [PMID: 37298502 DOI: 10.3390/ijms24119552] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/29/2023] [Revised: 05/24/2023] [Accepted: 05/28/2023] [Indexed: 06/12/2023] Open
Abstract
Iron accumulation in the brain accelerates Alzheimer's disease progression. To cure iron toxicity, we assessed the therapeutic effects of noncontact transcranial electric field stimulation to the brain on toxic iron deposits in either the Aβ fibril structure or the Aβ plaque in a mouse model of Alzheimer's disease (AD) as a pilot study. A capacitive electrode-based alternating electric field (AEF) was applied to a suspension of magnetite (Fe3O4) to measure field-sensitized reactive oxygen species (ROS) generation. The increase in ROS generation compared to the untreated control was both exposure-time and AEF-frequency dependent. The frequency-specific exposure of AEF to 0.7-1.4 V/cm on a magnetite-bound Aβ-fibril or a transgenic Alzheimer's disease (AD) mouse model revealed the degradation of the Aβ fibril or the removal of the Aβ-plaque burden and ferrous magnetite compared to the untreated control. The results of the behavioral tests show an improvement in impaired cognitive function following AEF treatment on the AD mouse model. Tissue clearing and 3D-imaging analysis revealed no induced damage to the neuronal structures of normal brain tissue following AEF treatment. In conclusion, our results suggest that the effective degradation of magnetite-bound amyloid fibrils or plaques in the AD brain by the electro-Fenton effect from electric field-sensitized magnetite offers a potential electroceutical treatment option for AD.
Collapse
Affiliation(s)
- Younshick Choi
- Departments of Biomedical Engineering & Radiology, School of Medicine, Daegu Catholic University, Daegu 42472, Republic of Korea
| | - Won-Seok Lee
- Departments of Biochemistry, School of Medicine, Daegu Catholic University, Daegu 42472, Republic of Korea
| | - Jaemeun Lee
- Korea R&D Center for Advanced Pharmaceuticals & Evaluation, Korea Institute of Toxicology, Daejeon 34114, Republic of Korea
| | - Sun-Hyun Park
- Korea R&D Center for Advanced Pharmaceuticals & Evaluation, Korea Institute of Toxicology, Daejeon 34114, Republic of Korea
| | - Sunwoung Kim
- Departments of Biomedical Engineering & Radiology, School of Medicine, Daegu Catholic University, Daegu 42472, Republic of Korea
| | - Ki-Hong Kim
- Department of Optometry and Vision Science, Daegu Catholic University, Kyungsan 38430, Republic of Korea
| | - Sua Park
- Department of Neurology, Inje University Ilsan Paik Hospital, Koyang 10380, Republic of Korea
| | - Eun Ho Kim
- Departments of Biochemistry, School of Medicine, Daegu Catholic University, Daegu 42472, Republic of Korea
| | - Jong-Ki Kim
- Departments of Biomedical Engineering & Radiology, School of Medicine, Daegu Catholic University, Daegu 42472, Republic of Korea
| |
Collapse
|
8
|
Das C, Ghosh NN, Pulhani V, Biswas G, Singhal P. Bio-functionalized magnetic nanoparticles for cost-effective adsorption of U(vi): experimental and theoretical investigation. RSC Adv 2023; 13:15015-15023. [PMID: 37200695 PMCID: PMC10187032 DOI: 10.1039/d3ra00799e] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/06/2023] [Accepted: 05/02/2023] [Indexed: 05/20/2023] Open
Abstract
U(vi) removal using cost-effective (production cost: $14.03 per kg), biocompatible, and superparamagnetic Cinnamomum tamala (CT) leaf extract-coated magnetite nanoparticles (CT@MNPs or CT@Fe3O4 nanoparticles) from water resources was studied. From pH-dependent experiments, the maximum adsorption efficiency was found to be at pH 8. Isotherm and kinetic studies were performed and found to follow Langmuir isotherm and pseudo-second order kinetics, respectively. The maximum adsorption capacity of CT@MNPs was calculated to be 45.5 mg of U(vi) per g of nanoparticles (NPs). Recyclability studies suggest that over 94% sorption was retained even after four consecutive cycles. The sorption mechanism was explained by the point of the zero-charge experiment and the XPS measurement. Additionally, calculations using density functional theory (DFT) were carried out to support the experimental findings.
Collapse
Affiliation(s)
- Chanchal Das
- Department of Chemistry, Cooch Behar Panchanan Barma University Cooch Behar West Bengal India 736101
| | | | - Vandana Pulhani
- Environmental Monitoring and Assessment Division, Bhabha Atomic Research Centre Mumbai 400085 India 91-22-2550-5313 91-22-2559-2349
| | - Goutam Biswas
- Department of Chemistry, Cooch Behar Panchanan Barma University Cooch Behar West Bengal India 736101
| | - Pallavi Singhal
- Environmental Monitoring and Assessment Division, Bhabha Atomic Research Centre Mumbai 400085 India 91-22-2550-5313 91-22-2559-2349
| |
Collapse
|
9
|
Bianchetti E, Oliveira AF, Scheinost AC, Di Valentin C, Seifert G. Chemistry of the Interaction and Retention of Tc VII and Tc IV Species at the Fe 3O 4(001) Surface. THE JOURNAL OF PHYSICAL CHEMISTRY. C, NANOMATERIALS AND INTERFACES 2023; 127:7674-7682. [PMID: 37144042 PMCID: PMC10150389 DOI: 10.1021/acs.jpcc.3c00688] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 01/31/2023] [Revised: 03/15/2023] [Indexed: 05/06/2023]
Abstract
The pertechnetate ion TcVIIO4 - is a nuclear fission product whose major issue is the high mobility in the environment. Experimentally, it is well known that Fe3O4 can reduce TcVIIO4 - to TcIV species and retain such products quickly and completely, but the exact nature of the redox process and products is not completely understood. Therefore, we investigated the chemistry of TcVIIO4 - and TcIV species at the Fe3O4(001) surface through a hybrid DFT functional (HSE06) method. We studied a possible initiation step of the TcVII reduction process. The interaction of the TcVIIO4 - ion with the magnetite surface leads to the formation of a reduced TcVI species without any change in the Tc coordination sphere through an electron transfer that is favored by the magnetite surfaces with a higher FeII content. Furthermore, we explored various model structures for the immobilized TcIV final products. TcIV can be incorporated into a subsurface octahedral site or adsorbed on the surface in the form of TcIVO2·xH2O chains. We propose and discuss three model structures for the adsorbed TcIVO2·2H2O chains in terms of relative energies and simulated EXAFS spectra. Our results suggest that the periodicity of the Fe3O4(001) surface matches that of the TcO2·2H2O chains. The EXAFS analysis suggests that, in experiments, TcO2·xH2O chains were probably not formed as an inner-shell adsorption complex with the Fe3O4(001) surface.
Collapse
Affiliation(s)
- Enrico Bianchetti
- Dipartimento
di Scienza dei Materiali, Università
di Milano Bicocca, Via
Roberto Cozzi 55, 20125 Milano, Italy
| | - Augusto F. Oliveira
- Institute
of Resource Ecology, Helmholtz-Zentrum Dresden-Rossendorf
(HZDR), Forschungsstelle Leipzig, Permoserstr. 15, 04318 Leipzig, Germany
- Theoretische
Chemie, Technische Universität Dresden, Bergstr. 66c, 01062 Dresden, Germany
| | - Andreas C. Scheinost
- Institute
of Resource Ecology, Helmholtz-Zentrum Dresden-Rossendorf
(HZDR), Bautzner Landstr.
400, 01328 Dresden, Germany
- The
Rossendorf Beamline (ROBL) European Synchrotron Radiation Facility
(ESRF), Avenue des Martyrs
71, 38043 Grenoble, France
| | - Cristiana Di Valentin
- Dipartimento
di Scienza dei Materiali, Università
di Milano Bicocca, Via
Roberto Cozzi 55, 20125 Milano, Italy
- BioNanoMedicine
Center NANOMIB, Università di Milano
Bicocca, Via Raoul Follereau
3, 20900 Monza, Italy
| | - Gotthard Seifert
- Theoretische
Chemie, Technische Universität Dresden, Bergstr. 66c, 01062 Dresden, Germany
| |
Collapse
|
10
|
Bianchetti E, Perilli D, Di Valentin C. Improving the Oxygen Evolution Reaction on Fe 3O 4(001) with Single-Atom Catalysts. ACS Catal 2023; 13:4811-4823. [PMID: 37066046 PMCID: PMC10088028 DOI: 10.1021/acscatal.3c00337] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/23/2023] [Revised: 03/15/2023] [Indexed: 04/18/2023]
Abstract
Doping magnetite surfaces with transition-metal atoms is a promising strategy to improve the catalytic performance toward the oxygen evolution reaction (OER), which governs the overall efficiency of water electrolysis and hydrogen production. In this work, we investigated the Fe3O4(001) surface as a support material for single-atom catalysts of the OER. First, we prepared and optimized models of inexpensive and abundant transition-metal atoms, such as Ti, Co, Ni, and Cu, trapped in various configurations on the Fe3O4(001) surface. Then, we studied their structural, electronic, and magnetic properties through HSE06 hybrid functional calculations. As a further step, we investigated the performance of these model electrocatalysts toward the OER, considering different possible mechanisms, in comparison with the pristine magnetite surface, on the basis of the computational hydrogen electrode model developed by Nørskov and co-workers. Cobalt-doped systems were found to be the most promising electrocatalytic systems among those considered in this work. Overpotential values (∼0.35 V) were in the range of those experimentally reported for mixed Co/Fe oxide (0.2-0.5 V).
Collapse
Affiliation(s)
- Enrico Bianchetti
- Dipartimento
di Scienza dei Materiali, Università
di Milano Bicocca, Via Roberto Cozzi 55, 20125 Milano, Italy
| | - Daniele Perilli
- Dipartimento
di Scienza dei Materiali, Università
di Milano Bicocca, Via Roberto Cozzi 55, 20125 Milano, Italy
| | - Cristiana Di Valentin
- Dipartimento
di Scienza dei Materiali, Università
di Milano Bicocca, Via Roberto Cozzi 55, 20125 Milano, Italy
- BioNanoMedicine
Center NANOMIB, Università di Milano
Bicocca, Via Raoul Follereau
3, 20900 Monza, Italy
| |
Collapse
|
11
|
Bianchetti E, Di Valentin C. Effect of Surface Functionalization on the Magnetization of Fe 3O 4 Nanoparticles by Hybrid Density Functional Theory Calculations. J Phys Chem Lett 2022; 13:9348-9354. [PMID: 36190176 PMCID: PMC9575150 DOI: 10.1021/acs.jpclett.2c02186] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/13/2022] [Accepted: 09/28/2022] [Indexed: 06/16/2023]
Abstract
Surface functionalization is found to prevent the reduction of saturation magnetization in magnetite nanoparticles, but the underlying mechanism is still to be clarified. Through a wide set of hybrid density functional theory (HSE06) calculations on Fe3O4 nanocubes, we explore the effects of the adsorption of various ligands (containing hydroxyl, carboxylic, phosphonic, catechol, and silanetriol groups), commonly used to anchor surfactants during synthesis or other species during chemical reactions, onto the spin and structural disorder, which contributes to the lowering of the nanoparticle magnetization. The spin-canting is simulated through a spin-flip process at octahedral Fe ions and correlated with the energy separation between O2- 2p and FeOct3+ 3d states. Only multidentate bridging ligands hamper the spin-canting process by establishing additional electronic channels between octahedral Fe ions for an enhanced ferromagnetic superexchange interaction. The presence of anchoring organic acids also interferes with structural disorder, by disfavoring surface reconstruction.
Collapse
Affiliation(s)
- Enrico Bianchetti
- Dipartimento
di Scienza dei Materiali, Università
di Milano Bicocca, Via Cozzi 55, 20125Milano, Italy
| | - Cristiana Di Valentin
- Dipartimento
di Scienza dei Materiali, Università
di Milano Bicocca, Via Cozzi 55, 20125Milano, Italy
- BioNanoMedicine
Center NANOMIB, Università di Milano
Bicocca, 20900Monza, Italy
| |
Collapse
|
12
|
Shutikova MI, Stegailov VV. Frenkel pair formation energy for cubic Fe 3O 4in DFT + U calculations. JOURNAL OF PHYSICS. CONDENSED MATTER : AN INSTITUTE OF PHYSICS JOURNAL 2022; 34:475701. [PMID: 36137505 DOI: 10.1088/1361-648x/ac9440] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/25/2022] [Accepted: 09/22/2022] [Indexed: 06/16/2023]
Abstract
The cubic phase of magnetite is stabilized above the Verwey transition temperature of about 120 K via a complex electron-phonon interaction that is still not very well understood. In this work using the DFT + U method we describe our attempt to calculate point defect formation energies for this cubic phase in the static approximation. The electronic structure calculations and atomic relaxation peculiarities are discussed in this context. Only the cubic phase model with a small band gap and charge disproportionation (Fe2+/Fe3+) gives an adequate point defect formation energies, not the semi-metallic model. The relaxation of the local defect atomic structure and the relaxation of the surrounding crystal matrix are analyzed. Point defects cause only local perturbations of atomic positions and charge-orbital order. After analysis of the supercell size effects for up to 448 atoms, we justify the use of small supercells with 56 atoms to make calculations for the cubic phase. The extensive experimental results of Dieckmannet alon defects in magnetite at high temperature are deployed for comparison of our DFT + U results on Frenkel pair formation energies.
Collapse
Affiliation(s)
- M I Shutikova
- Joint Institute for High Temperatures of the Russian Academy of Sciences, Izhorskaya 13 Building 2, Moscow 125412, Russia
- Moscow Institute of Physics and Technologies (National Research University), Institutskij pereulok 9, Dolgoprudny, Moscow Region 141700, Russia
| | - V V Stegailov
- Joint Institute for High Temperatures of the Russian Academy of Sciences, Izhorskaya 13 Building 2, Moscow 125412, Russia
- Moscow Institute of Physics and Technologies (National Research University), Institutskij pereulok 9, Dolgoprudny, Moscow Region 141700, Russia
- HSE University, Myasnitskaya Ulitsa 20, Moscow 101000, Russia
| |
Collapse
|
13
|
Rehman AU, Atif M, Younas M, Rafique T, Wahab H, Ul-Hamid A, Iqbal N, Ali Z, Khalid W, Nadeem M. Unusual semiconductor-metal-semiconductor transitions in magnetite Fe 3O 4 nanoparticles. RSC Adv 2022; 12:12344-12354. [PMID: 35480359 PMCID: PMC9036052 DOI: 10.1039/d2ra00530a] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/25/2022] [Accepted: 04/19/2022] [Indexed: 01/14/2023] Open
Abstract
Magnetite (Fe3O4) nanoparticles were successfully prepared by a co-precipitation method. Rietveld refinement on the X-ray diffraction pattern confirmed the development of a single-phase cubic spinel structure with space group Fd3̄m. However, 57Fe Mössbauer spectroscopy suggested the presence of Fe3+ and Fe2.5+ (mixed Fe3+ and Fe2+) ions at the tetrahedral and octahedral sites of the inverse spinel structure, respectively. Impedance spectroscopy measurements showed a discontinues variation in the temperature dependence of the sample's resistive behavior, indicating the appearance of semiconductor–metal–semiconductor like transitions between the temperature range of 293 and 373 K. A similar dual transition was also observed from the dielectric and conductivity measurements around the same temperature regions. The observed unusual transition is explained in term of the competitive effects among the hopping of localized/delocalized and short-range/long-range charge carriers present in the sample. Moreover, the prepared sample exhibits colossal dielectric permittivity (∼106), reduced tangent loss (∼0.2) and moderate conductivity (>10−6 S cm−1) values, making Fe3O4 nanoparticles a potential candidate for electromagnetic absorbing materials. Herein, we report the existence of a novel semiconductor–metal–semiconductor type transition in Fe3O4 nanoparticles by employing impedance spectroscopy techniques.![]()
Collapse
Affiliation(s)
- Atta Ur Rehman
- Functional Materials Lab, Department of Physics, Air University PAF Complex E-9 Islamabad Pakistan
| | - M Atif
- Functional Materials Lab, Department of Physics, Air University PAF Complex E-9 Islamabad Pakistan
| | - M Younas
- Polymer Composite Group, Physics Division, Directorate of Science, PINSTECH P.O. Nilore Islamabad Pakistan
| | - T Rafique
- Functional Materials Lab, Department of Physics, Air University PAF Complex E-9 Islamabad Pakistan
| | - H Wahab
- Polymer Composite Group, Physics Division, Directorate of Science, PINSTECH P.O. Nilore Islamabad Pakistan
| | - A Ul-Hamid
- Core Research Facilities, King Fahd University of Petroleum & Minerals Dhahran 31261 Saudi Arabia
| | - N Iqbal
- US-Pakistan Centre for Advanced Studies in Energy (USPCAS-E), NUST H-12 Islamabad 44000 Pakistan
| | - Z Ali
- Functional Materials Lab, Department of Physics, Air University PAF Complex E-9 Islamabad Pakistan
| | - W Khalid
- Functional Materials Lab, Department of Physics, Air University PAF Complex E-9 Islamabad Pakistan
| | - M Nadeem
- Polymer Composite Group, Physics Division, Directorate of Science, PINSTECH P.O. Nilore Islamabad Pakistan
| |
Collapse
|
14
|
Attfield JP. Magnetism and the Trimeron Bond. CHEMISTRY OF MATERIALS : A PUBLICATION OF THE AMERICAN CHEMICAL SOCIETY 2022; 34:2877-2885. [PMID: 35814039 PMCID: PMC9261838 DOI: 10.1021/acs.chemmater.2c00275] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/27/2022] [Revised: 03/14/2022] [Indexed: 05/06/2023]
Abstract
A review of progress in understanding the Verwey transition in magnetite (Fe3O4) over the past decade is presented. This electronic and structural transition at T V ≈ 125 K was reported in 1939 and has since been a contentious issue in magnetism. Long range Fe2+/Fe3+ charge ordering has been confirmed below the transition from crystal structure refinement, and Fe2+ orbital ordering and formation of trimerons through weak bonding of Fe2+ states to two Fe neighbors has been discovered. This model has accounted for many spectroscopic observations such as the 57Fe NMR frequencies. The trimeron lifetime has been measured, and trimeron soft modes have been observed. The origin of the first to second order crossover of Verwey transitions in doped magnetites has been revealed by a nanoparticle study. Electronic and structural fluctuations are found to persist to temperatures far above T V and local structural distortions track the bulk magnetization, disappearing at the 850 K Curie transition. New binary mixed-valent iron oxides discovered at high pressure are found to have electronic transitions and orbital molecule ground states similar to those of magnetite.
Collapse
|
15
|
Time- and Spectrally-Resolved Photoluminescence Study of Alloyed Cd xZn 1-xSe yS 1-y/ZnS Quantum Dots and Their Nanocomposites with SPIONs in Living Cells. Int J Mol Sci 2022; 23:ijms23074061. [PMID: 35409422 PMCID: PMC8999546 DOI: 10.3390/ijms23074061] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/03/2022] [Revised: 03/30/2022] [Accepted: 04/04/2022] [Indexed: 12/18/2022] Open
Abstract
Magnetic-luminescent composites based on semiconductor quantum dots (QDs) and superparamagnetic iron oxide nanoparticles (SPIONs) can serve as a platform combining visualization and therapy. Here, we report the construction of QD-SPION nanocomposites based on synthesized SPIONs and alloyed QDs (CdxZn1−xSeyS1−y)/ZnS solubilized with L-cysteine molecules. The study of the spectral-luminescence characteristics, the kinetics of luminescence decay show the composite’s stability in a solution. After incubation with HeLa cells, QDs, SPIONs, and their composites form clusters on the cell surface and associate with endosomes inside the cells. Component-wise analysis of the photoluminescence decay of cell-associated QDs/SPIONs provides information about their localization and aggregate status.
Collapse
|
16
|
Creutzburg M, Sellschopp K, Gleißner R, Arndt B, Vonbun-Feldbauer GB, Vonk V, Noei H, Stierle A. Surface structure of magnetite (111) under oxidizing and reducing conditions. JOURNAL OF PHYSICS. CONDENSED MATTER : AN INSTITUTE OF PHYSICS JOURNAL 2022; 34:164003. [PMID: 35051906 DOI: 10.1088/1361-648x/ac4d5a] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/06/2021] [Accepted: 01/20/2022] [Indexed: 06/14/2023]
Abstract
We report on differences in the magnetite (111) surface structure when prepared under oxidizing and reducing conditions. Both preparations were done under UHV conditions at elevated temperatures, but in one case the sample was cooled down while keeping it in an oxygen atmosphere. Scanning tunneling microscopy after each of the preparations showed a different apparent morphology, which is discussed to be an electronic effect and which is reflected in the necessity of using opposite bias tunneling voltages in order to obtain good images. Surface x-ray diffraction revealed that both preparations lead to Fe vacancies, leading to local O-terminations, the relative fraction of which depending on the preparation. The preparation under reducing conditions lead to a larger fraction of Fe-termination. The geometric structure of the two different terminations was found to be identical for both treatments, even though the surface and near-surface regions exhibit small compositional differences; after the oxidizing treatment they are iron deficient. Further evidence for the dependence of iron vs oxygen fractional surface terminations on preparation conditions comes from Fourier transform infrared reflection-absorption spectroscopy, which is used to study the adsorption of formic acid. These molecules dissociate and adsorb in chelating and bidentate bridging geometries on the Fe-terminated areas and the signal of typical infrared absorption bands is stronger after the preparation under reducing conditions, which results in a higher fraction of Fe-termination. The adsorption of formic acid induced an atomic roughening of the magnetite (111) surface which we conclude from the quantitative analysis of the crystal truncation rod data. The roughening process is initiated by atomic hydrogen, which results from the dissociation of formic acid after its adsorption on the surface. Atomic hydrogen adsorbs at surface oxygen and after recombination with another H this surface hydroxyl can form H2O, which may desorb from the surface, while iron ions diffuse into interstitial sites in the bulk.
Collapse
Affiliation(s)
- Marcus Creutzburg
- Centre for X-Ray and Nano Science CXNS, Deutsches Elektronen-Synchrotron DESY, Notkestr. 85, 22607 Hamburg, Germany
| | - Kai Sellschopp
- Institute of Advanced Ceramics, Hamburg University of Technology (TUHH), Denickestr. 15, 21073 Hamburg, Germany
| | - Robert Gleißner
- Centre for X-Ray and Nano Science CXNS, Deutsches Elektronen-Synchrotron DESY, Notkestr. 85, 22607 Hamburg, Germany
- Department of Physics, University of Hamburg, Luruper Chaussee 149, 22607 Hamburg, Germany
| | - Björn Arndt
- Centre for X-Ray and Nano Science CXNS, Deutsches Elektronen-Synchrotron DESY, Notkestr. 85, 22607 Hamburg, Germany
| | - Gregor B Vonbun-Feldbauer
- Institute of Advanced Ceramics, Hamburg University of Technology (TUHH), Denickestr. 15, 21073 Hamburg, Germany
| | - Vedran Vonk
- Centre for X-Ray and Nano Science CXNS, Deutsches Elektronen-Synchrotron DESY, Notkestr. 85, 22607 Hamburg, Germany
| | - Heshmat Noei
- Centre for X-Ray and Nano Science CXNS, Deutsches Elektronen-Synchrotron DESY, Notkestr. 85, 22607 Hamburg, Germany
| | - Andreas Stierle
- Centre for X-Ray and Nano Science CXNS, Deutsches Elektronen-Synchrotron DESY, Notkestr. 85, 22607 Hamburg, Germany
- Department of Physics, University of Hamburg, Luruper Chaussee 149, 22607 Hamburg, Germany
| |
Collapse
|
17
|
Eppstein R, Caspary Toroker M. On the Interplay Between Oxygen Vacancies and Small Polarons in Manganese Iron Spinel Oxides. ACS MATERIALS AU 2022; 2:269-277. [PMID: 36855379 PMCID: PMC9888643 DOI: 10.1021/acsmaterialsau.1c00051] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Ternary spinel oxides are promising materials due to their potentially versatile properties resulting from the disorder inherent in their crystal structure. To fully unlock the potential of these materials, a deeper understanding of their electronic structures, both as pristine and defective crystals, is required. In the present work, we investigate the effects of oxygen vacancies on the electronic structure and charge transport properties of the ternary spinel oxide Mn x Fe3-x O4, modeled on epitaxial thin films of the material, using density functional theory + U (DFT + U). The formation energy of a single oxygen vacancy in the spinel cell is found to be large and unaffected by changes in stoichiometry, in agreement with experimental results. We find that the immediate vicinity of the vacancy has a marked impact on the formation energy. In particular, Mn cations are found to be preferred over Fe as sites for charge localization around the vacancy. Finally, we examine the charge transport in the defective cell using the formalism of Marcus theory and find that the activation barrier for electron small-polaron hopping between sites not adjacent to the vacancy is significantly increased, with a large driving force toward sites that reside on the same (001) plane as the vacancy. Hence, vacancies delay charge transport by increasing the activation barrier, attributed to a rearrangement of vacancy-released charge on the cations immediately neighboring the vacancy site. These results highlight the impact of oxygen vacancies on charge transport in spinel oxides.
Collapse
Affiliation(s)
- Roni Eppstein
- Department
of Materials Science and Engineering, Technion-Israel
Institute of Technology, Haifa 3200003, Israel
| | - Maytal Caspary Toroker
- Department
of Materials Science and Engineering, Technion-Israel
Institute of Technology, Haifa 3200003, Israel,The
Nancy and Stephen Grand Technion Energy Program, Haifa 3200003, Israel,
| |
Collapse
|
18
|
Doping effect of Cu (II) in the adsorption of CrO42- by the Fe3O4 (1 1 1) surface: A theoretical study. Chem Phys Lett 2021. [DOI: 10.1016/j.cplett.2021.138984] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
|
19
|
Choquehuanca A, Ruiz-Montoya JG, La Rosa-Toro Gómez A. Discoloration of methylene blue at neutral pH by heterogeneous photo-Fenton-like reactions using crystalline and amorphous iron oxides. OPEN CHEM 2021. [DOI: 10.1515/chem-2021-0077] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
Abstract
Abstract
Different iron oxides were evaluated for the discoloration of methylene blue (MB) at neutral pH by heterogeneous photo-Fenton-like reactions with a UV-LED lamp. Fe3O4, α-Fe2O3, and a-FeOOH catalysts were synthesized and characterized by X-ray diffraction, scanning electron microscopy (SEM), Raman spectroscopy, Fourier transform infrared spectroscopy, and adsorption isotherms of N2. The results show high crystallinity and relatively low surface areas for Fe3O4 and α-Fe2O3, and amorphous structure with high surface area for the case of a-FeOOH. The discoloration of MB by iron oxides as catalysts was studied using UV-Vis spectroscopy. Despite the relative high adsorption of MB for magnetite (12%) compared to the other oxides, it shows a slow discoloration kinetics. Besides, amorphous oxide (named a-FeOOH) shows a higher discoloration kinetics with negligible adsorption capacity. The pseudo first-order kinetic constant values for Fe3O4, α-Fe2O3, and a-FeOOH are 5.31 × 10−3, 6.89 × 10−3, and 13.01 × 10−3 min−1; and the discoloration efficiencies at 120 min were 56, 60, and 82%, respectively. It was testified that low crystallinity iron oxide can be used in the efficient discoloration of MB by photo-Fenton process with a hand UV-A lamp.
Collapse
Affiliation(s)
- Astrid Choquehuanca
- Laboratorio de Investigación de Electroquímica Aplicada, Facultad de Ciencias, Universidad Nacional de Ingeniería , 15333 Lima , Perú
- Center for the Development of Advanced Materials and Nanotechnology, Universidad Nacional de Ingeniería , 15333 Lima , Peru
| | - José G. Ruiz-Montoya
- Laboratorio de Investigación de Electroquímica Aplicada, Facultad de Ciencias, Universidad Nacional de Ingeniería , 15333 Lima , Perú
- Center for the Development of Advanced Materials and Nanotechnology, Universidad Nacional de Ingeniería , 15333 Lima , Peru
| | - Adolfo La Rosa-Toro Gómez
- Laboratorio de Investigación de Electroquímica Aplicada, Facultad de Ciencias, Universidad Nacional de Ingeniería , 15333 Lima , Perú
- Center for the Development of Advanced Materials and Nanotechnology, Universidad Nacional de Ingeniería , 15333 Lima , Peru
| |
Collapse
|
20
|
Assadi MHN, Gutiérrez Moreno JJ, Hanaor DAH, Katayama-Yoshida H. Exceptionally high saturation magnetisation in Eu-doped magnetite stabilised by spin-orbit interaction. Phys Chem Chem Phys 2021; 23:20129-20137. [PMID: 34551040 DOI: 10.1039/d1cp02164h] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
The significance of the spin-orbit interaction is very well known in compounds containing heavier elements such as the rare-earth Eu ion. Here, through density functional calculations, we investigated the effect of the spin-orbit interaction on the magnetic ground state of Eu doped magnetite (Fe3O4:EuFe). By examining all possible spin alignments between Eu and magnetite's Fe, we demonstrate that Eu, which is most stable when doped at the tetrahedral site, adapts a spin almost opposite the substituted Fe. Consequently, because of smaller spin cancellation between the cations on the tetrahedral site (FeTet and EuTet) and the cations on the octahedral sites (FeOct), Fe3O4:EuFe exhibits a maximum saturation magnetisation of 9.451 μB per f.u. which is significantly larger than that of undoped magnetite (calculated to be 3.929 μB per f.u.). We further show that this large magnetisation persists through additional electron doping. However, additional hole doping, which may unintentionally occur in Fe deficient magnetite, can reduce the magnetisation to values smaller than that of the undoped magnetite. The results presented here can aid in designing highly efficient magnetically recoverable catalysts for which both magnetite and rare earth dopants are common materials.
Collapse
Affiliation(s)
- M Hussein N Assadi
- School of Materials Science and Engineering, The University of New South Wales, NSW 2052, Australia.
| | - José Julio Gutiérrez Moreno
- Department of Computer Applications in Science and Engineering, Barcelona Supercomputing Center (BSC), C/Jordi Girona 31, 08034 Barcelona, Spain
| | - Dorian A H Hanaor
- Fachgebiet Keramische Werkstoffe, Technische Universität Berlin, 10623 Berlin, Germany
| | - Hiroshi Katayama-Yoshida
- Center for Spintronics Research Network, Graduate School of Engineering, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-8656, Japan
| |
Collapse
|
21
|
Radoń A, Kądziołka-Gaweł M, Łukowiec D, Gębara P, Cesarz-Andraczke K, Kolano-Burian A, Włodarczyk P, Polak M, Babilas R. Influence of Magnetite Nanoparticles Shape and Spontaneous Surface Oxidation on the Electron Transport Mechanism. MATERIALS (BASEL, SWITZERLAND) 2021; 14:5241. [PMID: 34576465 PMCID: PMC8469694 DOI: 10.3390/ma14185241] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 08/12/2021] [Revised: 08/31/2021] [Accepted: 09/08/2021] [Indexed: 12/14/2022]
Abstract
The spontaneous oxidation of a magnetite surface and shape design are major aspects of synthesizing various nanostructures with unique magnetic and electrical properties, catalytic activity, and biocompatibility. In this article, the roles of different organic modifiers on the shape and formation of an oxidized layer composed of maghemite were discussed and described in the context of magnetic and electrical properties. It was confirmed that Fe3O4 nanoparticles synthesized in the presence of triphenylphosphine could be characterized by cuboidal shape, a relatively low average particle size (9.6 ± 2.0 nm), and high saturation magnetization equal to 55.2 emu/g. Furthermore, it has been confirmed that low-frequency conductivity and dielectric properties are related to surface disordering and oxidation. The electric energy storage possibility increased for nanoparticles with a disordered and oxidized surface, whereas the dielectric losses in these particles were strongly related to their size. The cuboidal magnetite nanoparticles synthesized in the presence of triphenylphosphine had an ultrahigh electrical conductivity (1.02 × 10-4 S/cm at 10 Hz) in comparison to the spherical ones. At higher temperatures, the maghemite content altered the behavior of electrons. The electrical conductivity can be described by correlated barrier hopping or overlapping large polaron tunneling. Interestingly, the activation energies of electrons transport by the surface were similar for all the analyzed nanoparticles in low- and high-temperature ranges.
Collapse
Affiliation(s)
- Adrian Radoń
- Łukasiewicz Research Network—Institute of Non-Ferrous Metals, Sowinskiego 5 St., 44-100 Gliwice, Poland; (A.K.-B.); (P.W.); (M.P.)
- Faculty of Mechanical Engineering, Silesian University of Technology, Konarskiego 18 a St., 44-100 Gliwice, Poland; (D.Ł.); (K.C.-A.); (R.B.)
| | - Mariola Kądziołka-Gaweł
- A. Chelkowski Institute of Physics, University of Silesia, 75 Pułku Piechoty 1A St., 41-500 Chorzów, Poland;
| | - Dariusz Łukowiec
- Faculty of Mechanical Engineering, Silesian University of Technology, Konarskiego 18 a St., 44-100 Gliwice, Poland; (D.Ł.); (K.C.-A.); (R.B.)
| | - Piotr Gębara
- Institute of Physics, Czestochowa University of Technology, al. Armii Krajowej 19, 42-200 Czestochowa, Poland;
| | - Katarzyna Cesarz-Andraczke
- Faculty of Mechanical Engineering, Silesian University of Technology, Konarskiego 18 a St., 44-100 Gliwice, Poland; (D.Ł.); (K.C.-A.); (R.B.)
| | - Aleksandra Kolano-Burian
- Łukasiewicz Research Network—Institute of Non-Ferrous Metals, Sowinskiego 5 St., 44-100 Gliwice, Poland; (A.K.-B.); (P.W.); (M.P.)
| | - Patryk Włodarczyk
- Łukasiewicz Research Network—Institute of Non-Ferrous Metals, Sowinskiego 5 St., 44-100 Gliwice, Poland; (A.K.-B.); (P.W.); (M.P.)
| | - Marcin Polak
- Łukasiewicz Research Network—Institute of Non-Ferrous Metals, Sowinskiego 5 St., 44-100 Gliwice, Poland; (A.K.-B.); (P.W.); (M.P.)
| | - Rafał Babilas
- Faculty of Mechanical Engineering, Silesian University of Technology, Konarskiego 18 a St., 44-100 Gliwice, Poland; (D.Ł.); (K.C.-A.); (R.B.)
| |
Collapse
|
22
|
Pazoki F, Esfandiarpour R, Mohsenzadeh F, Mohammadpanah F, Heydari A. Molecular docking and DFT studies of a series of tetrazole derivatives and computational studies of Fe3O4@Phenyl phosphate creatine. J Mol Struct 2021. [DOI: 10.1016/j.molstruc.2021.130389] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
|
23
|
Enhancing CO2 Conversion to CO over Plasma-Deposited Composites Based on Mixed Co and Fe Oxides. Catalysts 2021. [DOI: 10.3390/catal11080883] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023] Open
Abstract
The hydrogenation of CO2 to produce CO and H2O, known as reverse-water-gas shift reaction (RWGS) is considered to be an important CO2 valorization pathway. This work is aimed at proposing the thin-film catalysts based on iron and cobalt oxides for this purpose. A series of Fe–Co nanocomposites were prepared by the plasma-enhanced chemical vapor deposition (PECVD) from organic cobalt and iron precursors on a wire-mesh support. The catalysts were characterized by SEM/EDX, XPS, XRD, and Raman spectroscopy and studied for hydrogenation of CO2 in a tubular reactor operating in the temperature range of 250–400 °C and atmospheric pressure. The Co-based catalyst, containing crystalline CoO phase, exhibited high activity toward CH4, while the Fe-based catalyst, containing crystalline Fe2O3/Fe3O4 phases, was less active and converted CO2 mainly into CO. Regarding the Fe–Co nanocomposites (incl. Fe2O3/Fe3O4 and CoO), even a small fraction of iron dramatically inhibited the production of methane. With increasing the atomic fraction of iron in the Fe–Co systems, the efficiency of the RWGS reaction at 400 °C increased up to 95% selectivity to CO and 30% conversion of CO2, which significantly exceeded the conversion for pure iron–based films (approx. 9%). The superior performance of the Fe–Co nanocomposites compared to “pure” Co and Fe–based films was proposed to be explained by assuming changes in the electronic structure of the catalyst resulting from the formation of p–n junctions between nanoparticles of cobalt and iron oxides.
Collapse
|
24
|
Liu H, Siani P, Bianchetti E, Zhao J, Di Valentin C. Multiscale simulations of the hydration shells surrounding spherical Fe 3O 4 nanoparticles and effect on magnetic properties. NANOSCALE 2021; 13:9293-9302. [PMID: 33983352 PMCID: PMC8230581 DOI: 10.1039/d1nr01014j] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 02/15/2021] [Accepted: 04/19/2021] [Indexed: 06/12/2023]
Abstract
Iron oxide magnetic nanoparticles (NPs) are excellent systems in catalysis and in nanomedicine, where they are mostly immersed in aqueous media. Even though the NP solvation by water is expected to play an active role, the detailed structural insight at the nanostructure oxide/water interface is still missing. Here, based on our previous efforts to obtain accurate models of dehydrated Fe3O4 NPs and of their magnetic properties and through multiscale molecular dynamics simulations combining the density functional tight binding method and force field, we unravel the atomistic details of the short range (chemical) and long range (physical) interfacial effects when magnetite nanoparticles are immersed in water. The influence of the first hydration shell on the structural, electronic and magnetic properties of Fe3O4 NPs is revealed by high-level hybrid density functional calculations. Hydrated Fe3O4 NPs possess larger magnetic moment than dehydrated ones. This work bridges the large gap between experimental studies on solvated Fe3O4 NPs and theoretical investigations on flat Fe3O4 surfaces covered with water and paves the way for further study of Fe3O4 NPs in biological environments.
Collapse
Affiliation(s)
- Hongsheng Liu
- Laboratory of Materials Modification by Laser, Ion and Electron Beams, Dalian University of Technology, Ministry of Education, Dalian 116024, China and Dipartimento di Scienza dei Materiali, Università di Milano-Bicocca, via R. Cozzi 55, I-20125 Milano, Italy.
| | - Paulo Siani
- Dipartimento di Scienza dei Materiali, Università di Milano-Bicocca, via R. Cozzi 55, I-20125 Milano, Italy.
| | - Enrico Bianchetti
- Dipartimento di Scienza dei Materiali, Università di Milano-Bicocca, via R. Cozzi 55, I-20125 Milano, Italy.
| | - Jijun Zhao
- Laboratory of Materials Modification by Laser, Ion and Electron Beams, Dalian University of Technology, Ministry of Education, Dalian 116024, China
| | - Cristiana Di Valentin
- Dipartimento di Scienza dei Materiali, Università di Milano-Bicocca, via R. Cozzi 55, I-20125 Milano, Italy.
| |
Collapse
|
25
|
Liu X, Wu M, Qu K, Gao P, Mi W. Atomic-Scale Mechanism of Grain Boundary Effects on the Magnetic and Transport Properties of Fe 3O 4 Bicrystal Films. ACS APPLIED MATERIALS & INTERFACES 2021; 13:6889-6896. [PMID: 33499585 DOI: 10.1021/acsami.0c21705] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/12/2023]
Abstract
In strongly correlated materials, change of the local lattice configuration is expected to tune or even generate new properties otherwise in the ideal bulk materials. For highly spin-polarized materials, the spin-dependent transport is sensitive to the local magnetic structure. Here, the artificial grain boundaries (GBs) with different tilt angles are produced in Fe3O4 films using SrTiO3 bicrystal substrates. The saturation magnetization of Fe3O4 bicrystal films is enhanced. The detailed atomic structural results combining with density functional theory calculations reveal that the elongated FeA-O bond length at GBs resulting in the reduction of charge transfer reduces the FeA magnetic moments, which enhances the total magnetic moments of Fe3O4. The in-plane rotation of the Fe3O4 lattice on bicrystal substrates alters the magnetization processes. Especially, the Fe3O4 bicrystal film with a tilt angle of 22.6° shows strong in-plane magnetic anisotropy due to the zigzag GBs. The altered magnetic anisotropy of Fe3O4 bicrystal films enhances the anisotropic magnetoresistance. The findings reveal the mechanism of GBs on the magnetic and transport properties and manifest that the strategy of utilizing GBs can tune the physical properties in highly spin-polarized materials.
Collapse
Affiliation(s)
- Xiang Liu
- Tianjin Key Laboratory of Low Dimensional Materials Physics and Processing Technology, School of Science, Tianjin University, Tianjin 300354, China
| | - Mei Wu
- International Center for Quantum Materials, School of Physics, Peking University, Beijing 100871, China
| | - Ke Qu
- Electron Microscopy Laboratory, School of Physics, Peking University, Beijing 100871, China
| | - Peng Gao
- International Center for Quantum Materials, School of Physics, Peking University, Beijing 100871, China
- Electron Microscopy Laboratory, School of Physics, Peking University, Beijing 100871, China
- Collaborative Innovation Center of Quantum Matter, Beijing 100871, China
| | - Wenbo Mi
- Tianjin Key Laboratory of Low Dimensional Materials Physics and Processing Technology, School of Science, Tianjin University, Tianjin 300354, China
| |
Collapse
|
26
|
Siani P, Bianchetti E, Liu H, Di Valentin C. Parametrization of the Fe-O water cross-interaction for a more accurate Fe 3O 4/water interface model and its application to a spherical Fe 3O 4 nanoparticle of realistic size. J Chem Phys 2021; 154:034702. [PMID: 33499628 DOI: 10.1063/5.0035678] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
The accurate description of iron oxides/water interfaces requires reliable force field parameters that can be developed through comparison with sophisticated quantum mechanical calculations. Here, a set of CLASS2 force field parameters is optimized to describe the Fe-Owater cross-interaction through comparison with hybrid density functional theory (HSE06) calculations of the potential energy function for a single water molecule adsorbed on the Fe3O4 (001) surface and with density functional tight binding (DFTB+U) molecular dynamics simulations for a water trilayer on the same surface. The performance of the new parameters is assessed through the analysis of the number density profile of a water bulk (12 nm) sandwiched between two magnetite slabs of large surface area. Their transferability is tested for water adsorption on the curved surface of a spherical Fe3O4 nanoparticle of realistic size (2.5 nm).
Collapse
Affiliation(s)
- Paulo Siani
- Dipartimento di Scienza dei Materiali, Università di Milano-Bicocca, via R. Cozzi 55, 20125 Milano, Italy
| | - Enrico Bianchetti
- Dipartimento di Scienza dei Materiali, Università di Milano-Bicocca, via R. Cozzi 55, 20125 Milano, Italy
| | - Hongsheng Liu
- Dipartimento di Scienza dei Materiali, Università di Milano-Bicocca, via R. Cozzi 55, 20125 Milano, Italy
| | - Cristiana Di Valentin
- Dipartimento di Scienza dei Materiali, Università di Milano-Bicocca, via R. Cozzi 55, 20125 Milano, Italy
| |
Collapse
|
27
|
Magnetite (Fe3O4) Nanoparticles in Biomedical Application: From Synthesis to Surface Functionalisation. MAGNETOCHEMISTRY 2020. [DOI: 10.3390/magnetochemistry6040068] [Citation(s) in RCA: 96] [Impact Index Per Article: 24.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
Nanotechnology has gained much attention for its potential application in medical science. Iron oxide nanoparticles have demonstrated a promising effect in various biomedical applications. In particular, magnetite (Fe3O4) nanoparticles are widely applied due to their biocompatibility, high magnetic susceptibility, chemical stability, innocuousness, high saturation magnetisation, and inexpensiveness. Magnetite (Fe3O4) exhibits superparamagnetism as its size shrinks in the single-domain region to around 20 nm, which is an essential property for use in biomedical applications. In this review, the application of magnetite nanoparticles (MNPs) in the biomedical field based on different synthesis approaches and various surface functionalisation materials was discussed. Firstly, a brief introduction on the MNP properties, such as physical, thermal, magnetic, and optical properties, is provided. Considering that the surface chemistry of MNPs plays an important role in the practical implementation of in vitro and in vivo applications, this review then focuses on several predominant synthesis methods and variations in the synthesis parameters of MNPs. The encapsulation of MNPs with organic and inorganic materials is also discussed. Finally, the most common in vivo and in vitro applications in the biomedical world are elucidated. This review aims to deliver concise information to new researchers in this field, guide them in selecting appropriate synthesis techniques for MNPs, and to enhance the surface chemistry of MNPs for their interests.
Collapse
|
28
|
Bhattacharjee S, Mazumder N, Mondal S, Panigrahi K, Banerjee A, Das D, Sarkar S, Roy D, Chattopadhyay KK. Size-modulation of functionalized Fe 3O 4: nanoscopic customization to devise resolute piezoelectric nanocomposites. Dalton Trans 2020; 49:7872-7890. [PMID: 32469013 DOI: 10.1039/d0dt01167c] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/24/2023]
Abstract
Magnetite (Fe3O4), a representative relaxor multiferroic material, possesses fundamentally appealing multifaceted size-dependent properties. Herein, to evaluate a prototype spinel transition metal oxide (STMO), monodispersed and highly water-dispersible spherical magnetite nanoparticles (MNPs) with an enormous size range (3.7-242.8 nm) were synthesized via a facile microwave-assisted and polyol-mediated solvothermal approach at a controlled temperature and pressure using unique crystallite growth inhibitors. The excellent long-term colloidal stability of the MNPs in a polar environment and increase in their zeta potential confirmed the coordinative effect of the carboxylate groups derived from the covalent surface functionalization, which was also validated by FTIR spectroscopy, TGA and XPS analysis. The optical bandgap (Eg) between the crystal field split-off bands, which was calculated using the absorption spectra, increased gradually with a decrease in size of the MNPs within a broad UV-Vis range (1.59-4.92 eV). The red-shifting of the asymmetric Raman peaks with a smaller size and short-range electron-phonon coupling could be explained by the modified phonon confinement model (MPCM), whereas ferrimagnetic nature rejigged by superparamagnetism was verified from Mössbauer analysis. These stoichiometric, non-toxic, polar and magnetic nanocrystals are not only ideal for biomedical applications, but also suitable as electroactive porous host networks. Finally, the size-modulated MNPs were incorporated in poly(vinylidene fluoride) [PVDF]-based polytype nanogenerators as an electret filler to demonstrate their piezoelectric performance (VOC∼115.95 V and ISC∼1.04 μA), exhibiting substantial electromagnetic interference shielding.
Collapse
|
29
|
Ruan T, Wang B, Yang Y, Zhang X, Song R, Ning Y, Wang Z, Yu H, Zhou Y, Wang D, Liu H, Dou S. Interfacial and Electronic Modulation via Localized Sulfurization for Boosting Lithium Storage Kinetics. ADVANCED MATERIALS (DEERFIELD BEACH, FLA.) 2020; 32:e2000151. [PMID: 32159890 DOI: 10.1002/adma.202000151] [Citation(s) in RCA: 31] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/07/2020] [Revised: 02/14/2020] [Accepted: 02/25/2020] [Indexed: 05/26/2023]
Abstract
Structural modulation endows electrochemical hybrids with promising energy storage properties owing to their adjustable interfacial and/or electronic characteristics. For MXene-based materials, however, the facile but effective strategies for tuning their structural properties at nanoscale are still lacking. Herein, 3D crumpled S-functionalized Ti3 C2 Tx substrate is rationally integrated with Fe3 O4 /FeS heterostructures via coprecipitation and subsequent partial sulfurization to induce a highly active and stable electrode architecture. The unique heterostructures with tuned electronic properties can induce improved kinetics and structural stability. The surface engineering by S terminations on the MXene further unlocks extra (pseudo)capacitive lithium storage. Serving as anode for lithium storage, the optimized electrode delivers an excellent long-term cycling stability (913.9 mAh g-1 after 1000 cycles at 1 A g-1 ) and superior rate capability (490.4 mAh g-1 at 10 A g-1 ). Moreover, the (de)lithiation pathways associated with energy storage mechanisms are further revealed by operando X-ray diffraction, in situ electroanalytical techniques, and first-principles calculations. The hybrid electrode is proved to undergo stepwise phase transformations during discharging but a relatively uniform reconversion during charging, suggesting an asymmetric conversion mechanism. This work provides a novel strategy for designing high-performance hybrids and paves the way for in-depth understanding of complex lithium intercalation and conversion reactions.
Collapse
Affiliation(s)
- Tingting Ruan
- MIIT Key Laboratory of Critical Materials Technology for New Energy Conversion and Storage, School of Chemistry and Chemical Engineering, Harbin Institute of Technology, Harbin, 150001, China
| | - Bo Wang
- MIIT Key Laboratory of Critical Materials Technology for New Energy Conversion and Storage, School of Chemistry and Chemical Engineering, Harbin Institute of Technology, Harbin, 150001, China
- School of Materials Science and Engineering, Harbin Institute of Technology, Harbin, 150001, China
| | - Yubo Yang
- College of Materials Science and Engineering, Key Laboratory of Advanced Functional Materials, Ministry of Education, Beijing University of Technology, Beijing, 100124, China
| | - Xu Zhang
- College of Materials Science and Engineering, Key Laboratory of Advanced Functional Materials, Ministry of Education, Beijing University of Technology, Beijing, 100124, China
| | - Rensheng Song
- MIIT Key Laboratory of Critical Materials Technology for New Energy Conversion and Storage, School of Chemistry and Chemical Engineering, Harbin Institute of Technology, Harbin, 150001, China
| | - Yu Ning
- MIIT Key Laboratory of Critical Materials Technology for New Energy Conversion and Storage, School of Chemistry and Chemical Engineering, Harbin Institute of Technology, Harbin, 150001, China
| | - Zhenbo Wang
- MIIT Key Laboratory of Critical Materials Technology for New Energy Conversion and Storage, School of Chemistry and Chemical Engineering, Harbin Institute of Technology, Harbin, 150001, China
| | - Haijun Yu
- College of Materials Science and Engineering, Key Laboratory of Advanced Functional Materials, Ministry of Education, Beijing University of Technology, Beijing, 100124, China
| | - Yu Zhou
- School of Materials Science and Engineering, Harbin Institute of Technology, Harbin, 150001, China
| | - Dianlong Wang
- MIIT Key Laboratory of Critical Materials Technology for New Energy Conversion and Storage, School of Chemistry and Chemical Engineering, Harbin Institute of Technology, Harbin, 150001, China
| | - Huakun Liu
- Institute for Superconducting and Electronic Materials, Australian Institute of Innovative Materials, University of Wollongong, Wollongong, NSW, 2500, Australia
| | - Shixue Dou
- Institute for Superconducting and Electronic Materials, Australian Institute of Innovative Materials, University of Wollongong, Wollongong, NSW, 2500, Australia
| |
Collapse
|
30
|
Liu H, Bianchetti E, Siani P, Di Valentin C. Insight into the interface between Fe 3O 4 (001) surface and water overlayers through multiscale molecular dynamics simulations. J Chem Phys 2020; 152:124711. [PMID: 32241149 DOI: 10.1063/1.5140268] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023] Open
Abstract
In this work, we investigate the Fe3O4 (001) surface/water interface by combining several theoretical approaches, ranging from a hybrid functional method (HSE06) to density-functional tight-binding (DFTB) to molecular mechanics (MM). First, we assess the accuracy of the DFTB method to correctly reproduce HSE06 results on structural details and energetics and available experimental data for adsorption of isolated water, dimers, and trimers up to a water monolayer. Second, we build two possible configurations of a second and a third overlayer and perform molecular dynamics simulations with DFTB, monitoring the water orientation, the H-bond network, and the ordered water structure formation. To make our models more realistic, we then build a 12 nm-thick water multilayer on top of the Fe3O4 (001) surface slab model, which we investigate through MM-molecular dynamics (MD). The water layer structuring, revealed by the analysis of the atomic positions from a long MM-MD run for this large MM model, extends up to about 6-7 Å and nicely compares with that observed for a water trilayer model. However, MM and DFTB MD simulations show some discrepancy due to the poor description of the Fe⋯OH2 distance in MM that calls for further work in the parameterization of the model.
Collapse
Affiliation(s)
- Hongsheng Liu
- Dipartimento di Scienza dei Materiali, Università di Milano-Bicocca, via Cozzi 55, 20125 Milano, Italy
| | - Enrico Bianchetti
- Dipartimento di Scienza dei Materiali, Università di Milano-Bicocca, via Cozzi 55, 20125 Milano, Italy
| | - Paulo Siani
- Dipartimento di Scienza dei Materiali, Università di Milano-Bicocca, via Cozzi 55, 20125 Milano, Italy
| | - Cristiana Di Valentin
- Dipartimento di Scienza dei Materiali, Università di Milano-Bicocca, via Cozzi 55, 20125 Milano, Italy
| |
Collapse
|
31
|
Degaga GD, Trought M, Nemsak S, Crumlin EJ, Seel M, Pandey R, Perrine KA. Investigation of N 2 adsorption on Fe 3O 4(001) using ambient pressure X-ray photoelectron spectroscopy and density functional theory. J Chem Phys 2020; 152:054717. [PMID: 32035447 DOI: 10.1063/1.5138941] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
Reactions on iron oxide surfaces are prevalent in various chemical processes from heterogeneous catalysts to minerals. Nitrogen (N2) is known to dissociate on iron surfaces, a precursor for ammonia production in the Haber-Bosch process, where the dissociation of N2 is the limiting step in the reaction under equilibrium conditions. However, little is known about N2 adsorption on other iron-based materials, such as iron oxide surfaces that are ubiquitous in soils, steel pipelines, and other industrial materials. An atomistic description is reported for the binding of N2 on the Fe3O4(001) surface using first principles calculations with ambient pressure X-ray photoelectron spectroscopy. Two primary adsorption sites are experimentally identified from N2 dissociation on Fe3O4(001). The electronic signatures associated with the valence band region unambiguously show how the electronic structure of magnetite transforms near ambient pressures due to the binding of atomic nitrogen to different surface sites. Overall, the experimental and theoretical results of our study bridge the gap between ultra-high vacuum studies and reaction conditions to provide insight into other nitrogen-based chemistry on iron oxide surfaces that impact the agriculture and energy industries.
Collapse
Affiliation(s)
- Gemechis D Degaga
- Department of Physics, Michigan Technological University, 1400 Townsend Drive, Houghton, Michigan 49931-1295, USA
| | - Mikhail Trought
- Department of Chemistry, Michigan Technological University, 1400 Townsend Drive, Houghton, Michigan 49931-1295, USA
| | - Slavomir Nemsak
- Advanced Light Source, Lawrence Berkeley National Laboratory, 1 Cyclotron Road, Berkeley, California 94720-8229, USA
| | - Ethan J Crumlin
- Advanced Light Source, Lawrence Berkeley National Laboratory, 1 Cyclotron Road, Berkeley, California 94720-8229, USA
| | - Max Seel
- Department of Physics, Michigan Technological University, 1400 Townsend Drive, Houghton, Michigan 49931-1295, USA
| | - Ravindra Pandey
- Department of Physics, Michigan Technological University, 1400 Townsend Drive, Houghton, Michigan 49931-1295, USA
| | - Kathryn A Perrine
- Department of Chemistry, Michigan Technological University, 1400 Townsend Drive, Houghton, Michigan 49931-1295, USA
| |
Collapse
|
32
|
Bhattacharjee S, Banerjee A, Mazumder N, Chanda K, Sarkar S, Chattopadhyay KK. Negative capacitance switching in size-modulated Fe 3O 4 nanoparticles with spontaneous non-stoichiometry: confronting its generalized origin in non-ferroelectric materials. NANOSCALE 2020; 12:1528-1540. [PMID: 31854416 DOI: 10.1039/c9nr07902e] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/10/2023]
Abstract
Persistent low-frequency negative capacitance (NC) dispersion has been detected in half-metallic polycrystalline magnetite (Fe3O4) nanoparticles with varying sizes from 13 to 236 nm under the application of moderate dc bias. Using the Havriliak-Negami model, 3D Cole-Cole plots were employed to recapitulate the relaxation times (τ) of the associated oscillating dipoles, related shape parameters (α, β) and resistivity for the nanoparticles with different sizes. The universal Debye relaxation (UDR) theory requires a modification to address the shifted quasi-static NC-dispersion plane in materials showing both +ve and -ve capacitances about a transition/switching frequency (f0). A consistent blue-shift in 'f0' is observed with increasing external dc field and decreasing particle size. Based on this experimental data, a generalized dispersion scheme is proposed to fit the entire positive and negative capacitance regime, including the diverging transition point. In addition, a comprehensive model is discussed using phasor diagrams to differentiate the underlying mechanisms of the continuous transition from -ve to +ve capacitance involving localized charge recombination or time-dependent injection/displacement currents, which has been adequately explored in the scientific literature, and the newly proposed 'capacitive switching' phenomenon. An inherent non-stoichiometry due to iron vacancies [Fe3(1-δ)O4], duly validated from first principles calculations, builds up p-type nature, which consequently promotes more covalent and heavier dipoles and slows the dipolar relaxations; this is incommensurate with Maxwell-Wagner interfacial polarization (MWIP) dynamics. This combinatorial effect is likely responsible for the sluggish response of the associated dipoles and the stabilization of NC.
Collapse
|
33
|
Sanchez-Lievanos KR, Tariq M, Brennessel WW, Knowles KE. Heterometallic trinuclear oxo-centered clusters as single-source precursors for synthesis of stoichiometric monodisperse transition metal ferrite nanocrystals. Dalton Trans 2020; 49:16348-16358. [DOI: 10.1039/d0dt01369b] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/20/2023]
Abstract
Solvothermal reactions of MIIFe2III(μ3-O)(μ2-O2CR)6(H2O)3 (R = CF3, M = Fe, Co, Ni, Cu, Zn) clusters produce monodisperse, phase-pure MFe2O4 nanocrystals.
Collapse
Affiliation(s)
| | - Mehrin Tariq
- Department of Chemistry
- University of Rochester
- Rochester
- USA
| | | | | |
Collapse
|
34
|
Liu H, Di Valentin C. Shaping Magnetite Nanoparticles from First Principles. PHYSICAL REVIEW LETTERS 2019; 123:186101. [PMID: 31763909 DOI: 10.1103/physrevlett.123.186101] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/17/2019] [Revised: 09/12/2019] [Indexed: 06/10/2023]
Abstract
Iron oxide magnetic nanoparticles (NPs) are stimuli-responsive materials at the forefront of nanomedicine. Their realistic finite temperature simulations are a formidable challenge for first-principles methods. Here, we use density functional tight binding to open up the required time and length scales and obtain global minimum structures of Fe_{3}O_{4} NPs of realistic size (1400 atoms, 2.5 nm) and of different shapes, which we then refine with hybrid density functional theory methods to accomplish proper electronic and magnetic properties, which have never been accurately described in simulations. On this basis, we develop a general empirical formula and prove its predictive power for the evaluation of the total magnetic moment of Fe_{3}O_{4} NPs. By converting the total magnetic moment into the macroscopic saturation magnetization, we rationalize the experimentally observed dependence with shape. We also reveal interesting reconstruction mechanisms and unexpected patterns of charge ordering.
Collapse
Affiliation(s)
- Hongsheng Liu
- Dipartimento di Scienza dei Materiali, Università di Milano-Bicocca, via Roberto Cozzi 55, I-20125 Milano, Italy
| | - Cristiana Di Valentin
- Dipartimento di Scienza dei Materiali, Università di Milano-Bicocca, via Roberto Cozzi 55, I-20125 Milano, Italy
| |
Collapse
|
35
|
Liu X, Mi W. Electronic transport properties and magnetoresistance in the Fe 3O 4/SiO 2/p-Si heterostructure with an in-plane current geometry. Phys Chem Chem Phys 2019; 21:7518-7523. [PMID: 30895978 DOI: 10.1039/c9cp00033j] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Abstract
In traditional electronic devices, the electronic charge is manipulated to realize different functions. The fascinating control of electronic spin in conventional semiconductors increases the probability of occurrence of spin-dependent transport properties. Herein, the injection of electronic spin into a Si wafer with in-plane geometry was achieved by Fe3O4, which acted as a spin injector. At high temperatures, the resistivity of Fe3O4 is far less than that of a p-Si wafer. Moreover, above 190 K, the current-voltage (I-V) characteristic and magnetoresistance (MR) of the proposed heterostructure are dominated by the intrinsic properties of a polycrystalline Fe3O4 film, and the in-plane current flows in the Fe3O4 layer. Due to the increased resistivity of Fe3O4 at low temperatures, the in-plane conductive channel gradually switches from Fe3O4 to Si. The spin injection from Fe3O4 results in a spin-polarized space charge region in p-Si. The heterostructure shows an MR of up to -76.1% at 90 K due to the spin-dependent transport of electrons in p-Si. With a further decrease in temperature, the I-V characteristic of the heterostructure shows negative differential resistance below 80 K due to band bending at the Fe3O4/SiO2/p-Si interface.
Collapse
Affiliation(s)
- Xiang Liu
- Tianjin Key Laboratory of Low Dimensional Materials Physics and Preparation Technology, School of Science, Tianjin University, Tianjin 300354, China.
| | | |
Collapse
|
36
|
Liu H, Seifert G, Di Valentin C. An efficient way to model complex magnetite: Assessment of SCC-DFTB against DFT. J Chem Phys 2019; 150:094703. [PMID: 30849917 DOI: 10.1063/1.5085190] [Citation(s) in RCA: 16] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
Magnetite has attracted increasing attention in recent years due to its promising and diverse applications in biomedicine. Theoretical modelling can play an important role in understanding magnetite-based nanomaterials at the atomic scale for a deeper insight into the experimental observations. However, calculations based on density functional theory (DFT) are too costly for realistically large models of magnetite nanoparticles. Classical force field methods are very fast but lack of precision and of the description of electronic effects. Therefore, a cheap and efficient quantum mechanical simulation method with comparable accuracy to DFT is highly desired. Here, a less computationally demanding DFT-based method, i.e., self-consistent charge density functional tight-binding (SCC-DFTB), is adopted to investigate magnetite bulk and low-index (001) surfaces with newly proposed parameters for Fe-O interactions. We report that SCC-DFTB with on-site Coulomb correction provides results in quantitatively comparable agreement with those obtained by DFT + U and hybrid functional methods. Therefore, SCC-DFTB is valued as an efficient and reliable method for the description magnetite. This assessment will promote SCC-DFTB computational studies on magnetite-based nanostructures that attract increasing attention for medical applications.
Collapse
Affiliation(s)
- Hongsheng Liu
- Dipartimento di Scienza dei Materiali, Università di Milano-Bicocca, Via R. Cozzi 55, I-20125 Milano, Italy
| | - Gotthard Seifert
- Theoretische Chemie, Technische Universität Dresden, 01062 Dresden, Germany
| | - Cristiana Di Valentin
- Dipartimento di Scienza dei Materiali, Università di Milano-Bicocca, Via R. Cozzi 55, I-20125 Milano, Italy
| |
Collapse
|
37
|
Molteni G, Ferretti AM, Trioni MI, Cargnoni F, Ponti A. The azide–alkyne cycloaddition catalysed by transition metal oxide nanoparticles. NEW J CHEM 2019. [DOI: 10.1039/c9nj04690a] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
Fe3O4, MnFe2O4, CoFe2O4, MnO, and α-MnS nanoparticles catalyse the title reaction by the ligation of the azide on the surface of the nanoparticle.
Collapse
Affiliation(s)
- Giorgio Molteni
- Dipartimento di Chimica
- Università degli Studi di Milano
- 20133 Milano
- Italy
| | - Anna M. Ferretti
- Laboratorio di Nanotecnologie
- Istituto di Scienze e Tecnologie Molecolari (ISTM)
- Consiglio Nazionale delle Ricerche
- 20138 Milano
- Italy
| | - Mario Italo Trioni
- Istituto di Scienze e Tecnologie Molecolari (ISTM)
- Consiglio Nazionale delle Ricerche
- 20133 Milano
- Italy
| | - Fausto Cargnoni
- Istituto di Scienze e Tecnologie Molecolari (ISTM)
- Consiglio Nazionale delle Ricerche
- 20133 Milano
- Italy
| | - Alessandro Ponti
- Laboratorio di Nanotecnologie
- Istituto di Scienze e Tecnologie Molecolari (ISTM)
- Consiglio Nazionale delle Ricerche
- 20138 Milano
- Italy
| |
Collapse
|
38
|
Liu H, Di Valentin C. Bulk-terminated or reconstructed Fe 3O 4(001) surface: water makes a difference. NANOSCALE 2018; 10:11021-11027. [PMID: 29868664 PMCID: PMC6001776 DOI: 10.1039/c8nr02279h] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/19/2018] [Accepted: 05/08/2018] [Indexed: 05/22/2023]
Abstract
Surfaces and their interaction with water play an important role in most of materials' applications. Magnetite has attracted continued interest in the fields of catalysis, spintronic devices, magnetic resonance imaging (MRI) and drug delivery. In this work, water adsorption and its effect on the stability diagram and on the electronic structure of the Fe3O4(001) surface are investigated by hybrid density functional theory calculations combined with an ab initio atomistic thermodynamic approach. We span a wide range of gaseous O2 and vapor H2O partial pressures. At low water pressure, a reconstructed SCV surface model is confirmed to be the most stable model at common working O2 partial pressures. However, at high water coverage, an unexpected stability inversion is observed that makes the hydrated bulk-terminated DBT surface the most favored. These results open up new horizons in Fe3O4 surface chemistry when working in an aqueous environment and are of key importance to develop rational strategies to surface engineering for high performance Fe3O4 nanomaterials.
Collapse
Affiliation(s)
- Hongsheng Liu
- Dipartimento di Scienza dei Materiali, Università di Milano-Bicocca, via R. Cozzi 55, I-20125 Milano, Italy.
| | | |
Collapse
|