Projects / Programmes
Self-assembly of molecular nanomagnets in nanotubes
| Code |
Science |
Field |
Subfield |
| 1.02.01 |
Natural sciences and mathematics |
Physics |
Physics of condesed matter |
| Code |
Science |
Field |
| P260 |
Natural sciences and mathematics |
Condensed matter: electronic structure, electrical, magnetic and optical properties, supraconductors, magnetic resonance, relaxation, spectroscopy |
molecular nanomagnets, nanotubes, self-assembly
Researchers (8)
Organisations (3)
Abstract
The focus of this project is on different ways of adding magnetic properties to nanotubes from elsewhere; filling of nanotubes either by transition metal nanoparticles or by molecular nanomagnets. In general we will initiate our research in two directions: filling of carbon nanotubes and/or nanohorns and filling of titania-derived nanotubes. Prepared samples will be carefully structurally characterised by using different microscopy techniques (scanning electron (SEM) and transmission electron microscopy (TEM)) in order to determine the stability of the complex, structural details (i.e. the arrangement of molecular nanomagnets for instance) and the interaction between the host nanotubes and the magnetic “impurity”. In the next stage, the magnetic properties will be determined by using magnetisation (SQUID) and electron paramagnetic (EPR) techniques. Effective spin Hamiltonian parameters will be determined from the simulation of the data and the results will be discussed in the framework of the superparamagnetic properties of the complexes.
Significance for science
The project "Self assembly of molecular nanomagnets in nanotubes" represents a very original approach towards modification of electronic and magnetic properties of different nanostructures. Molecular nanomagnets, which occurred almost twenty years ago, emerged as a very promising material in a spintronic technology. At about the same time carbon nanotubes have ignited "nanorevolution" mainly because of their exceptional electronic and mechanical properties. The merger of these two concepts, such as we are trying to achieve in this project, into a single material with a special magnetic and transport properties has already led to a completely new systems with unusual properties.
In the framework of realization of the research project, we developed original experimental and theoretical techniques. Scientific contribution can be divided into two parts:
1) Synthesis of new materials
As the first in the world, we have developed effective methods for the intercalation of titanate nanotubes with transition metal elements. These techniques are now generally divided into two methods: in-situ and ex-situ. Our results have been also noticed internationally, as we reported on them at international conferences, published articles and already received the first citations of our work. It is important to note, that with appropriate adaptation of our methods we could use them also in related systems. Thus, we were first to demonstrate,that it is possible to grow a very clean MnOx nanotubes in the presence of Fe3 + ions during the hydrothermal synthesis. Intercalation of Mn12AcBr molecular nanomagnets into carbon nanotubes is also very original idea and, to the best of our knowledge, has not yet been published in world literature. The reason for this probably lies in the extraordinary complexity of the preparation of the samples. However, our idea for the use of Soxhlet extraction will be likely widely used for the intercalation of other species into the carbon nanotubes.
2) Measurements of magnetic properties
Since we have all the measurements performed on a completely new models, all our results that we obtained from the SQUID and EPR measurements are original. Especially we would like to highlight our original approach for understanding the EPR spectra of titanate Cu-doped nanotubes. Through a combination of conventional CW-EPR and pulsed EPR sequences (in particular to mention here ESEEM techniques), we can with incredible accuracy determine the position of Cu2+ ions in the titanate network. Such an assignment is important for understanding of the transport properties of these materials. It is also important for any further applications that will (could) result from the outcome of this project. Cu2+ ions and CuO nanoparticles with size below 10 nm can actually act as excellent catalytic centers for the degradation of hydrocarbon gases, or as the basis for the manufacture of highly sensitive sensor elements. Our research requires the development of appropriate software for the simulation of very complex EPR spectra. This software, based on Matlab software code, will also become an important integral part of our research.
Significance for the country
The relevance of the project for Slovenia is as follows:
1. The development of interdisciplinary research:
In the project we are trying to exploit the synergy between the physical and chemical groups in Slovenia. In the project consortium we have also established Slovenian physicists, as well as chemists. We have also added young researchers. The idea of such approach is that with the coordinated work of physicists and chemists we will try to develop a radically new material with the targeted physical-chemical properties.
2. The development of applied research:
In large measure this project still includes primarily basic research, since we are trying to get to a totally new materials and techniques. Nevertheless, at each stage of the project realisation when we are trying to design new systems we have different application niches that would be most appropriate for our systems in mind. In particular we are intrigued by their sensorial and catalytic properties. It is important to stress that this field today represent a huge market potential. In the context of the current research we also think about the patent application in order to protect some of our achievements.
3. Transfer of knowledge in Slovenia:
As we have mentioned, in the context of this project, we work closely together with three groups from the U.S., France and Croatia. We started to work with these groups because currently Slovenia lacks sufficient knowledge in certain specific areas. By working closely together in the realization of this project, we expect that we will part of their knowledge successfully transfer to Slovenia.
4. The development of young researchers:
We have successfully integrated young researchers into the project team. These researchers will have special knowledge and experience that would be potentially interesting for the Slovenian industry; They will have profound knowledge in the field of nanotechnology, chemistry and physical measurements.
5. Involvement in international projects:
Based on the results of published reports in international journals and conferences, we were invited to the two projects submitted to the European Community (both projects are currently on the waiting list after evaluation in the second round). We are also included as one of the leading members of the new COST project, which was approved and started in november 2009.
Most important scientific results
Annual report
2008,
final report,
complete report on dLib.si
Most important socioeconomically and culturally relevant results
Annual report
2008,
final report,
complete report on dLib.si
