Projects
Research Projects
Thermo-mechanical aspects of BaFeO3 based perovskite ceramics for solid oxide cells
- FONDECYT Regular
- Project No.: 1240319
- 2024 - 2026
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Principal Investigator
Ali Akbari-Fakhrabadi -
Co-Investigator
Viviana Meruane
Mixed ionic and electronic conducting (MIEC) oxides with perovskite-related structures have attracted significant attention due to extensive applications for solid oxide cells (SOCs) and oxygen separation membrane reactors as highly efficient electrochemical energy conversion devices. Among all MIEC perovskites, BaFeO3 based materials as
potential cobalt-free, iron-rich and cost-effective mixed ionic and electronic conductive perovskite oxides for air electrode in SOCs with improved long-term stability and high compatibility with other cell components as well as favorable electrochemical performance at intermediate temperatures is becoming a new research trend. BaFeO3 demonstrates different or mixed structure types as multi-phase material depending on atmosphere, temperature, the synthesis method, and thermal history, which affect the oxygen concentration in its lattice, which have profound effects upon the electrical and magnetic properties. It has a high temperature disordered symmetric cubic crystal structure above 900 °C, which transforms to ordered low symmetric crystal structures upon cooling which deteriorate oxygen permeability due to much less three-dimensional oxygen diffusion paths comparing with cubic lattice. Also, its linear elastic behavior at elevated temperatures will turn to non-linear ferroelastic behavior at room temperature. Doping strategies have been often adopted to stabilize the cubic lattice structure of the BaFeO3 oxide. It has been demonstrated that the appropriate selection of the A- and B-site dopants (or dopants combinations) can stabilize its high temperature cubic structure to room temperature and change its electrical, electrochemical, and mechanical characteristics. Due to the high thermal reduction tolerance, favorable mixed conduction, outstanding oxygen reaction catalytic ability and cost-effective feature, active research continues to optimize doping strategies for BaFeO3 parent compounds to stabilize its high temperature cubic lattice structure at lower temperatures to be used in low temperature SOCs and improve their electrochemical performance and phase stability. While the electrochemical performance of SOCs has been greatly improved, a broad adoption of the technology still awaits meeting the challenge of long-term mechanical and chemical stability. Despite a number of publications reporting successful improvement of the melectrochemical performance and chemical stability by composition optimization of novel materials for SOC´s air electrode, there is few research on their elastic, thermo-mechanical and creep behavior, which are fundamental knowledge to determine deformation response to forces and analyze mechanical stability specially at low temperatures when residual stresses magnitude could be significant and could affect SOC reliability during heating-cooling transients. It is realized that electrochemical degradation and mechanical failure of these multilayered devices can be suppressed by using novel materials for cell components and optimizing the microstructure to maintain their long-term stability. So, investigation on the elastic, thermo-mechanical and creep behavior of novel materials with optimized composition for high electrochemical performance is vital for studies on the mechanical reliability and durability of such cells.
1. Fabrication of nanostructure perovskite powders and their powder characteristics
2. Fabrication, densification studies, structural and microstructural characterizations of polycrystalline bulk perovskites
4. Effect of temperature on elastic behavior of polycrystalline bulk perovskites
5. Creep behavior of polycrystalline bulk perovskites
Time Dependent Creep Deformation of Lanthanum based Ferroelastic Perovskite Ceramics
- FONDECYT Regular
- Project No.: 1200141
- 2019 - 2023
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Principal Investigator
Ali Akbari-Fakhrabadi -
Co-Investigator
Viviana Meruane -
Co-Investigator
Roger Bustamante
The developments of Perovskite-structured ceramics with a flexible crystal structure (ABO3) which can be tailored by doping and/or co-doping of the A- and B-site cations and obtain various properties accordingly have attracted significant attention due to extensive applications as piezoelectric, ferroelectrics and multiferroics. These ferroic polycrystalline perovskites transform to low symmetry phases on cooling through the Curie temperature which leads to the possibility of the formation of different domains in alternating patterns surrounded by mobile domain walls. Applying external forces to such materials below their Curie temperature causes a non-linear behavior as well as hysteresis in stress–strain curves known as ferroelastic behavior due to domain switching and a time-dependent deformation behavior known as ferroelastic creep due to domain walls mobility.
Lanthanum metal oxides with a perovskite structure have attracted much attention because of their possible applications in solid oxide fuel cells (SOFCs), Oxygen transport membranes (OTMs) and chemical sensors. They display ferroelastic behavior which has been characterized by uniaxial compression, spherical indentation and impression techniques. Despite a number of publications concerning the spin-state, electrical and magnetic transitions, and the oxygen permeability, just a few papers have been published on the ferroelasticity, elastic hysteresis and ferroelastic creep of these materials due to their ferroelastic domain switching and dynamic of domain walls and their interaction with other defects in the structure.
In this research work, synthesis and fabrication of selected La-based perovskite structured (M’, M”: Co, Fe, Mn, and Al; 0≤x≤0.4, 0≤y≤0.5), based on built dataset of published literature and trained machine learning algorithms for material selection and doping strategies, by chemical route methods followed by calcination and densification studies have been proposed. X-ray diffraction and Raman spectroscopy techniques will be used for structural characterizations and Rietveld refinement analyses. We propose a comprehensive study on the effect of chemical compositions, microstructural and crystallographic characteristics, temperature and external force on the elasticity, internal friction and ferroelastic creep behavior of La-based perovskite oxides using impulse excitation (IET), compression and impression techniques. The final phase of the proposal is focused on comparison of impression and compression techniques and developing a phenomenological constitutive model for time-dependent creep deformation of ferroelastic perovskites.
- Synthesis of nanostructure perovskite powders and their powder characteristics
Fabrication, densification studies, structural and microstructural characterizations of polycrystalline bulk perovskites
Elastic modulus (E) and internal friction (Q-1) measurements
- Ferroelastic characterization of perovskites
Development on the synthesis, fabrication and characterization of La-based perovskite nanostructures for reversible solid oxide cells
- FONDECYT Initiation
- Project No.: 11160202
- 2016 - 2019
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Principal Investigator
Ali Akbari-Fakhrabadi
Reversible solid oxide cell (RSOC) technology as a solid-state and high efficient electrochemical energy conversion device is one of the most promising electricity storage/generation options and has been projected as a key component of the future electric grid to increase efficiency and allows large-scale penetration of intermittent renewable resources. It is constructed of a membrane electrode assembly comprising a laminated fuel electrode, solid electrolyte and oxygen electrode. Due to high temperature operation and having highly exothermic and endothermic reactions during fuel and electrolysis cell modes, respectively, one significant challenge of designing RSOC system is its thermal management. In this regard, several strategies including carefully controlling the RSOC stack temperature and pressure have been proposed. The feasibility of such stack operating conditions requires research and cell materials development for long-term durability.
The developments of perovskite materials with a flexible crystal structure (ABO3) have received many attentions as their structures can be tailored by doping and/or co-doping of the A- and B-site cations and obtain various properties accordingly. Despite many studies have concentrated on conduction properties and performance of newly developed perovskite materials, their associated mechanical properties studies is limited in the literature. Therefore in this work, La-based perovskite nanostructures has been proposed to investigate their structural, electrical and room and high temperature mechanical properties in order to improve their chemical stability and mechanical durability during fabrication and operation conditions by cations doping and co-doping strategies. The final phase of this investigation is focused on electrochemical performance analyses of the single cell assembly by fabrication of planar fuel electrode supported single cells.
1.Synthesis of nanostructure perovskite powders and their powder characteristics
2. Physical characterizations of prepared perovskite nanostructures
3. Mechanical characterizations of prepared perovskite nanostructures
4. Fabrication of a single cells and performance analyses by electrochemical measurements
- A. Akbari-Fakhrabadi, E.G. Toledo, J.I. Canales, V. Meruane, S.H. Chan, M.A. Gracia-Pinilla, “Effect of Sr2+ and Ba2+ doping on structural stability and mechanical properties of La2NiO4+δ”, Ceramics International, 2018, 44, 10551-10557.
- A. Akbari-Fakhrabadi, O. Rodriguez, R. Rojas, V. Meruane, M.H. Pishahang, “Ferroelastic behavior of LaCoO3: A comparison of impression and compression techniques”, Journal of European Ceramic Society, 2019, 39, 1569-1576.
Hydrid TiO2-MoS2/Carbon@Trimetallic Co based spinel oxide as advanced oxygen reduction electrocatalyst for fuel cell application
- FONDECYT Postdoctoral
- Project No.: 3220390
- 2022 - 2025
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Principal Investigator
Mudaliar Mahesh Margoni
The current research is intended to explore trimetallic Cobalt (Co) based spinel oxide electrocatalyst with special emphasis on design and synthesis for application as fuel cell. The pace of innovation in the present work is to develop carbon supported mono/-, bi/- and tri/-metallic Co based spinel oxide electrocatalyst and investigate the oxygen reduction reaction (ORR) and stability for fuel cell application. A comprehensive hybrid of TiO2/MoS2 and Carbon@trimetallic Co based spinel oxide electrocatalyst with improved ORR activity will also be developed. To investigate the structural, morphological, optical, electrical and electrochemical studies using sophisticated analytical techniques such as XRD, Raman and FTIR for structural confirmation, SEM and HRTEM for morphology and confirm the accurate size of the nanostructure and quantum dots, Electrochemical measurements. Further the single entity electro/-photochemistry will be study for all the synthesized nanoparticle in order to study not only the basic particle characterization such as chemical identity, sizing, concentration, porosity and agglomeration/aggregation state but also one can understand in depth about the mechanism and dynamics at single particle levels while performing photo/-electrochemical processes. Finally, Enhanced ORR activity, high stability, durability, reproducibility and compatibility towards oxidizing and reducing environment to improve the performance of fuel cells will be extensively studied. The synthesis of carbon supported mono/-, bi/- and tri/-metallic Co based spinel oxide electrocatalyst will be carried out using Hydrothermal technique followed by drying in hot air oven and annealing at high temperature in furnace. Whereas TiO2 nanotube /MoS2 quantum dots will be synthesized by hydrothermal method. Finally TiO2 nanotube/MoS2 and Carbon@trimetallic Co based spinel oxide hybrid electrocatalyst will be prepared using facile chemical method. The proposed research helps to synthesize carbon supported mono/-, bi/- and tri/- metallic Co based nanostructures as well as TiO2 nanotube-MoS2 quantum/trimetallic NiCo3-xFexO4 composite nanostructures as electrocatalysts for fuel cell application. In the course of research, the above samples will be synthesized with high electrocatalytic activity, high stability, durability, compatibility and reproducibility for fuel cell application. Also the prepared samples will be subjected to electrochemical and photoelectrochemical studies along with single entity electrochemistry by nano impact method. The results of the proposed research work will be published in leading international journals, conferences, seminars and workshops. Hence the results will reach the scientific community and the investigators working in this and related areas
Synthesis of XCo3O4 and XFeCo2O4 through hydrothermal technique where X is carbon based materials like reduced graphene oxide (rGO).
Preparation of trimetallic NiCo3-xFexO4 nanostructures by facile chemical technique.
Synthesis of carbon supported trimetallic NiCo3-xFexO4 nanostructures by facile chemical technique.
Preparation of TiO2 quantum dots and trimetallic NiCo3-xFexO4 hybrid nanostructures by facile chemical technique.
Synthesis of MoS2 quantum dots and trimetallic NiCo3-xFexO4 hybrid nanostructures by facile chemical technique.
To investigate the structural, morphological, optical, electrical and electrochemical studies using sophisticated analytical techniques.
To study and investigate the photo/-electrochemical activity of semiconducting nanostructures for energy conversion. Thereafter, studies on single entity electrochemistry on semiconducting materials TiO2/MoS2 quantum dots materials will be performed.
The samples will be prepared using solution based methods (Solvo/hydrothermal technique and if needed any other chemical technique will be employed) and will be subjected to characterization techniques like XRD, Raman and FTIR for structural confirmation, SEM and HRTEM for morphology and confirm the accurate size of the nanostructure and quantum dots.
Analytical response and redox behaviour and electrocatalytic activity, stability and reproducibility for the synthesized samples using electrochemical measurements like cyclic voltammetry. chronoamperometry, chronocoulometry and impedance measurement in order to study the nano impact method.
- Arun Thirumurugan, Prabakaran, R.Udayabhaskar, R.V.Mangalaraja, AliAkbari-Fakhrabadi, Carbon decorated octahedral shaped Fe3O4 and α-Fe2O3 magnetic hybrid nanomaterials for next generation supercapacitor applications, Applied Surface Science, 485, 147-157, 2019.
- T. Arun, T. K. Kumar, R. Udayabhaskar, and R. V Mangalaraja, A. Akbari-Fakhrabadi “Nano hexagonal Co3O4 platelets for supercapacitor applications” Mat. Research Exp. 6, 0850b1, 2019.
Novel Multiferroic BiFe1-xTxO3/CoFe2O4/RTO3 (R=rare earth; T = Mn, Ni and Cr) Nanocomposites and Thin Films: Structural, Vibrational, Magneto-electric Properties for spintronic applications
- FONDECYT Postdoctoral
- Project No.: 3180055
- 2018 - 2021
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Principal Investigator
Muneeswaran Muniyandi
Spin-based random access memory (spin-RAM) is a type of non-volatile information storage, which can be distinguished from permanent (secondary) or mass information storage such as tapes, had disk, CD, and DVD. While spin-RAM has a great advantage over other RAMs, it has some drawbacks of storage capacity and energy consumption. In order to overcome such drawbacks, development of spin-RAM with multiferroic heterostructures is important because no electric current is needed to write information but the application of an electric field can write and store information in the magnetic layer via magneto-electric effect. However, the energy efficient writing mechanism is still under debate. So far, there are different physical origins of magneto-electric effect in ferromagnetic/ferroelectric multiferroic heterostructures, e.g., magneto-electric coupling, interface chemical bonding coupling, and charging modulation coupling. Among them, magneto-electric coupling, where interaction between the magnetization and the strain transfer from a ferroelectric play a vital role, has been one of the most promising mechanisms to switch the magnetization in a controlled manner. Therefore, a detailed study of magneto-electric effects in multiferroic heterostructures can open a new avenue towards developing novel magnetic information storage technology that will be integrated in future spin-RAM devices. In this work, we focus on highly magnetism and ferroelectric materials which show fascinating study of enhance the magneto electric effect. Since the magnetic phase transition is associated with the cell volume and crystal symmetry, strain transfer at the BiFe1-xTxO3/CoFe2O4/RTO3 can manipulate the magnetic phases as well as magnetization orientation by electric field through magneto-electric effect. The purpose of this study is to present a clear demonstration of electric-field control of the magnetic properties of CoFe2O4, RTO3 based oxide such as magnetic phases and magnetization orientation. Electric-field control of spin wave excitation in this material is also the target of this study because it provides a clue to the mechanism of the electric-field induced magnetic phase transition as well as its potential for the use in magnonic information device applications.
- Synthesis and characterization of novel multiferroics BFO, CFO and RTO3 (R = rare earth, T = transition metal) nanocomposites, growth of thin films and heterostructures of these multiferroics.
- Field Emission Scanning Electron Microscope (FESEM) would investigate the morphology and thickness of the thin films and average surface roughness and inormation about domain orientation of BFO/CFO/RTO3 thin films using Atomic Force Microscopy (AFM) and Kelvin Probe Force Microscopy (KPFM), respectively.
- Nuclear Magnetic Resonance (NMR) studies will provide better insights into the magnetic structure, surface-interface phenomena, low energy spin excitations and electron spin correlations of the stated multiferroics.
- Raman spectroscopy studies will provide insights into the structural transition of the proposed materials.
- Ferroelectric properties would be investigated by recording polarization vs. electric field (P–E) loops using Sawyer–Tower circuit at different temperature to determine the remnant polarization (Pr) and electric coactivity (Ec).
- Measurement of magnetization as a function of electric field applied in plane and out-of-plane in VSM/SQUID magnetometer. Changes in magnetization as a function of applied field, anisotropy, order parameter from magnetization vs. temperature will be carried out using VSM/SQUID.
- M. Muneeswaran. A. Akbari‑Fakhrabadi1 · M. A. Gracia Pinilla, J. C. Denardin, Structural, electrical, ferroelastic behavior, and multiferroic properties of BiFeO3, Journal of Materials Science: Materials in Electronics, 2020, 31 (16), pp. 13141-13149. DOI: 10.1007/s10854-020-03865-y
Fabrication of Ferrite/Carbon hybrid nanomaterial for electrochemical energy storage applications
- FONDECYT Postdoctoral
- Project No.: 3170696
- 2017 - 2020
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Principal Investigator
Arun Thirumurugan
Carbon materials and carbon based composite hybrid materials are highly studied for the electrochemical energy storage applications. Our interest is on supercapacitors due to its high power density, fast charge-discharge rate, high capacitance, and superlong cycle life. Supercapacitors are the potential device which can complete the charge/discharge process in few seconds and it could able to produce high power density is in the order of 10 kW/kg. . Two types of supercapacitors are available based on the charge storage mechanism namely electrical double layer capacitors (EDLCs) and pseudo-capacitors. The electrode is made by using metal oxides, conducting polymers and carbon materials. Making hybrid nanostructures of carbon materials for supercapacitors with magnetic nanoparticle are in much interest due to the magnetic nature. In energy storage, the performance is subject to the properties of anode and cathode materials. Several advancements have been made to improve the efficiency of the batteries by applying new chemistry into it. RuO2, MnO2, NiO, Co3O4, V2O5 and other transition metal oxides are widely used as an electrode material. Currently, hybrid material such combination of different metal oxide and other carbon based materials are studied for the improvement in the performance. Our interest is to show the utilization of hybrid nanomaterial of ferrite with carbon layered structure for the better performance in electrochemical energy storage.
Materials can exhibit diamagnetic, paramagnetic, ferromagnetic, ferrimagnetic and antiferromagnetic behavior according to their magnetic nature. Magnetic materials can be classified as hard and soft magnetic materials based on the coercivity exhibited by them. Chemical methods have advantages to prepare magnetic materials due to controllable size, morphology and composition which are essential in the area of data storage, and biomedicine. However, the synthesis of non-agglomerated particles with uniform size and shape is a challenging task. In addition, the surface modification is simplest way to control the size and shape of magnetic nanostructures with required and improved biocompatible and physicochemical properties. Most of the reports have focused on the surface modification of super-paramagnetic iron oxide nanoparticles of single size for catalytic and sensor applications. However there are potential uses of magnetic nanoparticles in magnetic field related applications requires specific magnetic nanoparticles with higher saturation magnetization.
This project mainly focuses on the surface modification of the ferrite magnetic nanoparticles (MNPs) by carbon coating and the optimized hybrid nanomaterials are utilized to fabricate the supercapacitors.
- Synthesis of ferrite magnetic nanoparticles using chemical oxidation method.
- Formation of carbon layer on the ferrite magnetic nanoparticle.
- Investigation of structural properties of the prepared hybrid nanostructures.
- The magnetic properties of the hybrid structures will be analyzed using vibrating sample magnetometer.
- Raman and FTIR spectroscopic techniques will be used to characterize the local structure of the prepared materials and to get insight into the influence of influence of carbon on the ferrite nanostructures.
- Thermo-gravimetric (TG) analysis will be used to quantify the fraction of carbon on the hybrid nanostructures.
- The optimized carbon coated ferrite magnetic nanoparticles will be further subject to the analyses of their electrochemical properties.
- Arun Thirumurugan, Prabakaran, R.Udayabhaskar, R.V.Mangalaraja, AliAkbari-Fakhrabadi, Carbon decorated octahedral shaped Fe3O4 and α-Fe2O3 magnetic hybrid nanomaterials for next generation supercapacitor applications, Applied Surface Science, 485, 147-157, 2019.
- T. Arun, T. K. Kumar, R. Udayabhaskar, and R. V Mangalaraja, A. Akbari-Fakhrabadi “Nano hexagonal Co3O4 platelets for supercapacitor applications” Mat. Research Exp. 6, 0850b1, 2019.