Conveners
Advanced Materials and Processes for Energy (Posters)
- Estelina Silva (IFIMUP, Department of Physics and Astronomy)
- Diogo Santos (IST)
- Carlos Costa (University of Minho)
- Antonio Pereira Goncalves
Multiferroic materials have been under the spotlight due to their fundamental scientific interest and for potential applications in technology. Among these interesting materials are the group of compounds belonging to the Pyroxene family with general chemical formula AM(Si,Ge)2O6. More specifically, SrMnGe2O6 [1] and CaMnGe2O6[2] are isostructural, crystallizing with monoclinic C2/c symmetry...
There is a great need to control the thermal expansion (TE) in the technology industry, where devices can be degraded due to differences in TE. Negative thermal expansion (NTE) arises as a key to customize the TE. [1] Recent advances at the nanoscale, more precisely nanomaterials with 1D architecture have revealed that TE is a size-dependent feature. [2] FeCo alloys thin films have been...
In Europe, buildings are responsible for over 40% of energy consumption and greenhouse gas emissions, so that improving their sustainability is a much-needed demand for the construction sector. To reduce energy use and CO2 emissions, it is necessary to contain as much as possible the energy requirements of a building [1]. Among the several solutions studied, the development of materials with...
Population growth and improved lifestyle are responsible for the increase in energy demand. The commitment to renewable energies and batteries for energy storage represent one of the solutions to support continuous energy demands. Lithium-ion batteries (LIB) have the advantage over other batteries with respect to higher energy density by mass and volume, which allows smaller and lighter...
Recently, the demand for intelligent textiles and smart materials is growing in the world motivated by the market requests for innovative high-performance products [1]. Electrochemical energy storage systems like supercapacitors (SCs) are promising technologies to develop smart functionalities on textiles, particularly for the area of health and wellness [2]. Screen-printing has long been used...
Energy harvesting devices allowing to recover wasted energy from the environment are increasingly developed. Mechanical energy is the most interesting sources of power for energy harvesting and piezoelectric materials present excellent overall properties for the scavenging of wasted energy. Piezoelectric polymers and, in particular, polyvinylidene fluoride (PVDF), show appropriate mechanical...
Ocean related activities are often supported by offshore equipment with particular power demands. These are usually deployed at remote locations and have limited space, thus small energy harvesting technologies, such as photovoltaic panels or wind turbines, are used to power their instruments. However, the inherent energy sources are intermittent and have lower density and predictability than...
The ion beam analytical (IBA) techniques capabilities are enhanced when coupled to a scanning nuclear microprobe due to the possibility of: i) focusing the beam to sub-micrometer spot sizes and, ii) rastering the area under analysis. In this way, it is possible to obtain elemental distribution maps and the elemental depth profile in a fully quantitative manner.
The type of materials...
An important challenge of this century is to focus on the production of renewable and sustainable energy, which thrives on research in the development of photovoltaic (PV) materials [1] (solar energy to electricity) and photoelectrochemical (PEC) water-splitting materials (solar energy into chemical energy) [2]. Among the various PV and PEC materials, perovskite structured oxides (ABO3 where...
Currently available commercial thermoelectric generators contain expensive and potentially hazardous elements, such as Bi, Pb or Te. To overcome this hindrance, the application of alternative materials, like the p-type semiconductor mineral tetrahedrite (Cu12Sb4S13), is being studied. Tetrahedrite is a naturally occurring and abundant mineral with low toxicity that displays good electrical and...
This work intends to develop a theoretical model for the membrane processes on direct liquid fuel cells, particularly the direct borohydride-peroxide fuel cell (DBPFC), as a first step to create a numerical model. The DBPFC is based on the anodic oxidation of sodium borohydride (NaBH4) in alkaline solution with the simultaneous cathodic reduction of hydrogen peroxide (H2O2) in acid media. As...
Naturally Layered Perovskite structures with improper ferroelectricity [1, 2], such as the Ruddlesden-Popper calcium manganite compound Ca3Mn2O7, offer an alternative route to achieve non-expensive and high-performance room temperature multiferroic magnetoelectricity for information storage, sensors, and actuators or low power energy-efficient electronics. They allow exploring oxygen octahedra...
We present an ab-initio study performed by means of Density Functional Theory (DFT) and lattice dynamics to probe the octahedral distortions, which occur during the structural phase transitions of the quasi-2D layered perovskite Sr$_3$Hf$_2$O$_7$ compound. Such a system is characterized by a high-temperature I4/mmm (space group n. 139) centro-symmetric structure and a ground-state Cmc2$_1$...
The growing concerns on environmental impact require a new generation of materials and processes for sustainable electronics and energy storage systems [1]. In this scope, additive manufacturing techniques arise as an effective process to improve the sustainability of device fabrication [2]. In this work, direct-ink-writing was used to produce poly (vinylidene fluoride-co-hexafluoropropylene)...
The design of a transparent thermoelectric material is a promising technology for touch–screen displays and solar cell applications, rendering a more sustainable powering of the device. In order to enhance the thermoelectric performance, the films must have a high Seebeck coefficient, high electrical but low thermal conductivity [1]. For this purpose, ZnO thin films were deposited by magnetron...
Strong efforts are being carried out looking for efficient, clean and renewable energy sources to meet the decarbonization goals. With respect to solar energy, thin film photovoltaic (PV) systems based on CuInxGa1-xSe2 (CIGS) deserve special attention, due to its outstanding opto-electronic properties. Despite the high-efficiency devices produced by vacuum deposition processes, non-vacuum ones...
Thin and flexible micro thermoelectric generators (𝜇 -TEGs) are being envisaged as alternative power sources in the last decade [1]. They constitute a new business opportunity for the packaging industry such self-powered wearable mobile electronics and/or to be used on remote places for low power consumption devices. One approach to achieve this goal are by producing thin films using composite...
The recently-observed[1] self-assembly of salphen-based metal-organic frameworks (MOF) into networks of interconnected microrings with nano-thin strings may suggests a new intriguing tool for nanoscale patterning. In particular, their ability to align very small amounts of carbon nanotubes into ultra-low density percolating network promises a breakthrough in creating highly transparent...
Thermoelectric materials are important for power-generation devices that can convert waste heat into electrical energy. This conversion may have an important role in the current challenge for the development of alternative energy technologies.
In the present work, the intermetallic thermoelectric materials with the formula RCu9Sn4 (R=Nd, Pr, La, Y) and their stoichiometric variations...
Multiferroic composite materials are of great interest for technological applications due to the magnetoelectric coupling effect, by which an electric (magnetic) field may be used to control the magnetization (polarization). Being insulators, these materials find application in low power energy efficient electronics, due to their low joule heating effect. In the form of thin films the...
Keeping devices operating at adequate temperatures is necessary for numerous technological areas. One innovative component that can contribute to this control is the thermal switch (TS). TSs rely on the switching of thermal resistance between two states: during the “on” (“off”) state, the thermal resistance is minimized (maximized), thus maximizing (minimizing) the heat transfer. In this...
