Bachelor’s Theses
Graphene-based asymmetric supercapacitors
By thermal exfoliation of graphite oxide it is possible to obtain graphene on a macroscopic scale with a high specific surface area (> 500 m² / g) and good electrical properties. This material is particularly suitable for the production of electrodes for supercapacitor, namely devices placed between normal capacitors and batteries, useful for energy harvesting and storage. The thesis activity at the Nanocarbon Laboratory, Energy Unit, will involve the realization and study of new asymmetric supercapacitors based on graphene derivatives, able of storing more energy than their respective symmetrical devices.
Study of low environmental impact biochar-based supercapacitors
Bio-char is waste material produced by the pyro-gasification of biomass, used as a soil improver in agriculture. By virtue of its porosity and biocompatibility, the interest in this material has recently considerably increased, due to its use as inexpensive precursor for activated carbon. The activated (specific surface of 1000-2000 m²/g) and super-activated carbon (greater than 3000 m²/g) produced in the Nanocarbon Laboratory of the University of Parma have proved to be excellent electrodes in symmetrical supercapacitors, delivering capacities up to 100 F/g in devices. The thesis work will focus on the optimization of these devices, acting both on the chemical activation process of the bio-char, to control its microporosity, and on the identification of the most suitable water-based electrolytes.
Development of new graphene-based flexible devices for energy storage by means of the “laser-scribing” technique
Recently, new techniques have emerged for the scalable production of flexible devices based on graphene, by means of the photothermal conversion with laser of suitable precursors on a flexible support. The writing of the device with laser allows to reach high speed and precision in the process. In the Nanocarbon Laboratory of the University of Parma, Energy Unit, innovative miniaturized graphene-based supercapacitors are obtained via the “LightScribe Graphene” and the “Laser Induced Graphene” techniques, which have capacities of the order of 5000 F/m². The interest in these devices is in the field of “micro energy harvesting” and in the “Internet of Things” (IoT). The thesis work will focus on the optimization of these systems, to further improve their performance.
Master Theses
Study of new carbon nanostructures for the production of innovative ionic batteries
An important technological challenge in the coming years is how to increase the performance of the current electricity accumulators. Lithium batteries (LIBs) are now extensively used in electronic devices, but their high cost, also due to the scarce availability of lithium, the still low energy and specific powers that can be reached (especially when compared to those of fossil fuels), limit their possible application even on a large scale. Research carried out by the Nanocarbon Laboratory of the University of Parma has shown how carbon nanostructures, in particular some fullerene and graphene derivatives, can operate as efficient negative electrodes in innovative sodium ion batteries (SIBs). By virtue of the high natural availability of sodium, SIBs are inherently cheaper than LIBs and are also suitable for large-scale use. The proposed experimental thesis activity will be conducted at the Nanocarbon Laboratory and will consist in the synthesis, characterization and optimization of new materials based on carbon nanostructures, capable of operating as electrodes in SIBs. The most promising materials will then be tested in battery prototypes to evaluate their performance.
Novel room temperature solid fast-ion conductors based on carbon nanostructures
The extensive use of electrochemical energy accumulators in electronic devices and, in the near future, even on a large scale inside vehicles, poses serious safety problems. In fact, Li-ion batteries, which today represent the “state of the art” in this sector, still operate almost exclusively with liquid organic electrolytes, making these devices dangerous if short-circuited or damaged. Switching to the use of solid electrolytes would make batteries much safer, especially if one considers their use in the field of transport (EV). However, there are still no materials able to offer the necessary mechanical characteristics and good ionic conductivity to be used in devices that are competitive with those on the market. The research activity of the last few years of the Nanocarbon Laboratory at the University of Parma has shown how some fullerene based compounds and its derivatives behave as excellent Li ionic conductors already at room temperature, therefore potentially suitable for developing innovative electrolytes at solid state. The experimental thesis activity will be carried out at the Nanocarbon Laboratory and will consist in the synthesis of new materials based on carbon nanostructures, in particular fullerene derivatives, capable of showing significant ionic conductivity already at room temperature. The most promising materials will then be tested inside all-solid-state battery prototypes, to evaluate their electrochemical performance.
Synthesis and optimization of laser techniques for the assembling of low-cost graphene-based devices (in collaboration with the Information Engineering Department of Parma)
The development of new low-cost techniques for the production of graphene-based materials on a large scale has opened up new possible applications, in particular in the field of consumer electronics. The most interesting synthesis techniques in this area include the possibility of depositing conductive and porous graphene films using laser techniques, which allow the creation of micro-devices with precision at the micrometer scale. The interest in these devices iranges from small-scale energy storage and recovery (micro energy-storage and harvesting), to the realization of disposable biomedical sensors, to the so-called “wearable electronics” and “smart packaging”. At the Nanocarbon Laboratory of the University of Parma innovative graphene-based supercapacitors are obtained by the laser writing on flexible media (Lightscribe® and Laser Induced Graphene techniques). The proposed experimental thesis activity will consist in the optimization and downsizing of these devices, as well as in the study of new laser writing methods and precursor materials, for applications in flexible electronics. The work will be performed both at the Nanocarbon Laboratory and at the Information Engineering Department of Parma.
Nano-porous carbon for hydrogen storage applications for the automotive industry (in collaboration with the Department of Chemistry of Pavia)
The massive use of fossil fuels for energy production is causing epochal problems related to the pollution of our planet, global warming and energy sustainability. A possible solution must derive from the conversion to renewable sources and the use of non-polluting fuels. Hydrogen is a highly efficient energy carrier (three times more energy than gasoline for the same weight), widely available in nature, whose combustion does not produce greenhouse gases and can be directly converted into electricity with high efficiency. However, the transition to a “hydrogen-based economy” is still impeded, especially by the difficulties of efficiently storing this gas. One of the most promising methods is solid state hydrogen storage. Carbon nanostructures are among the most promising systems, because they are intrinsically cheap and biocompatible, characterized by hyerarchical porosity that allows them to adsorb significant quantities of hydrogen already at low working pressures, albeit also at very low temperatures (T = 77 K). Optimizing the binding energy with which the hydrogen molecule binds to carbon (bringing it to the 10-50 kJ/mol regime) would allow the practical application of these systems. The proposed thesis work, of an experimental nature, will consist in the synthesis of new materials with hierarchical porosity (micro- and meso-porosity) obtained starting from vegetable carbon (the so-called biochar) and/or through the use of templates, whose very high expected surface area (over 3000 m²/g) will allow the storage of large quantities of hydrogen. The absorption energy will be optimized through the functionalization of the materials with metallic nanoparticles.
Study of carbon nanostructures by means of muon and neutron spectroscopy
Carbon nanostructures, thanks to their low cost, biocompatibility, lightness and high mechanical and electronic properties, are natural candidates in energy storage systems, both as constituent materials of batteries, and as systems for gas storage (e.g. hydrogen). The research activity of the Carbon Nanostructures Laboratory in Parma has been studying the interaction of hydrogen with carbon nanostructures for several years, using very specific techniques, such as muon and neutron spectroscopy, thanks to a collaboration with the ISIS Neutron and Muon Source research center (Didcot, England). In particular, muon spectroscopy consists in the study of the evolution of the spin of polarized muons, which are implanted in matter and which, under particular conditions, behave as light isotopes of the hydrogen atom (muonium). Neutron spectroscopy, on the other hand, is extremely sensitive to the presence of hydrogen and allows to obtain structural and dynamic information on materials. The combination of these techniques has recently allowed us to identify a new interesting class of hydrogen absorbing materials, namely light alkali-cluster intercalated fullerites. The proposed experimental thesis activity will consist in the study of the hydrogen absorption and desorption mechanism in carbon nanostructures with these two powerful techniques.