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Thin films based on aluminum nitride were obtained by fs-laser assisted Pulsed Laser Deposition (fs-PLD) at room temperature on tantalum substrates for studying the electron emission performance in the temperature range 700- 1600 °C, so to investigate the possibility of their exploitation as thermionic cathodes. Results of structural, chemical and morphological analyses show the growth of nanostructured thin films with a significant oxygen contamination, forming a mixture of crystalline aluminum nitride and aluminum oxide as well as metallic aluminum inclusions. Despite the considerable presence of oxygen, the developed cathodes demonstrate to possess promising thermionic emission characteristics, with a work function of 3.15 eV, a valuable Richardson constant of 20.25 A cm−2K−2, and a highly thermo- electronic stability up to operating temperatures of 1600 °C. [ABSTRACT FROM AUTHOR]

Starting in January 2017, AMADEUS (www.amadeus-project.eu) is the first project funded by the European Commission to research on a new generation of materials and solid-state devices for ultra-high temperature energy storage and conversion. By exploring storage temperatures well beyond 1000 °C, one of the main objectives of the project is to create new PCMs (phase change materials) with latent heat in the range of 1000-2000 kWh/m3, an order of magnitude greater than that of typical salt-based PCMs used in concentrated solar power (CSP), along with developing advanced thermal insulation, PCM casing designs, and novel solid-state thermal-to-electric energy conversion devices able to operate at temperatures in the range of 1000-2000 °C. In particular, the project is investigating silicon-boron based alloys as PCMs and hybrid thermionic-photovoltaic (TIPV) devices for energy conversion. This paper describes the main project R&D activities and the results that have been attained during the first two years of the project. This includes the thermophysical characterization of Si-B alloys, the wettability and solubility analysis of said alloys with solid refractory materials, the numerical simulation of phase-change and heat losses through thermal insulation cover, as well as the realization of the two main proof-of-concept experiments: the TIPV converter, and the full latent heat energy storage system. [ABSTRACT FROM AUTHOR]

Starting in January 2017, AMADEUS (www.amadeus-project.eu) is the first project funded by the European Commission to research on a new generation of materials and solid state devices for ultra-high temperature energy storage and conversion. By exploring storage temperatures well beyond 1000 ºC the project aims at breaking the mark of ~ 600ºC rarely exceeded by current state of the art thermal energy storage (TES) systems. AMADEUS Project, through a collaborative research between seven European partners, aims to develop a novel concept of latent heat thermal energy storage (LHTES) systems with unprecedented high energy density. One of the main objectives of the project is to create new PCMs (phase change materials) with latent heat in the range of 1000-2000 kWh/m3, an order of magnitude greater than that of typical salt-based PCMs used in concentrated solar power (CSP), along with developing advanced thermal insulation, PCM casing designs, and novel solid-state heat to power conversion technologies able to operate at temperatures in the range of 1000-2000 ºC. In particular, the project will investigate Silicon-Boron alloys as PCMs and hybrid thermionic-photovoltaic (TIPV) devices for heat-to-power conversion. This paper describes the project R&D activities and the main results that have been attained during the first 6 months of work. This includes the first wettability and solubility analysis of liquid Si-B alloys, the numerical simulation of silicon phase-change and heat loss analysis through thermal insulation cover, as well as the first steps for the realization of the two main AMADEUS proof-ofconcept experiments: the TIPV converter, and the full LHTES device. [ABSTRACT FROM AUTHOR]

1-D and 2-D detector arrays have been realized on CVD-diamond. The relatively high resistivity of diamond in the dark allowed the fabrication of photoconductive 'sandwich' strip (1D) or pixel (2D) detectors: a semitransparent light-receiving back-side contact was used for detector biasing. Cross-talk between pixels was limited by using intermediate guard contacts connected at the same ground potential of the pixels. Each pixel photocurrent was conditioned by a read-out electronics composed by a high sensitive integrator and a Σ-Δ ADC converter. The overall 500 μs conversion time allowed a data acquisition rate up to 2 kSPS. The measured fast photoresponse of the samples in the ns time regime suggests to use the proposed devices for fine tuning feedback of high-power pulsed-laser cavities, whereas solar-blindness guarantees high performance in UV beam diagnostics also under high intensity background illumination. Offering unique properties in terms of thermal conductivity and visible-light transparency, diamond represents one of the most suitable candidate for the detection of high-power UV laser emission. The technology of laser beam profiling is evolving with the increase of excimer lasers applications that span from laser-cutting to VLSI and MEMS technologies. Indeed, to improve emission performances, fine tuning of the laser cavity is required. In such a view, the development of a beam-profiler, able to work in real-time between each laser pulse, is mandatory. [ABSTRACT FROM AUTHOR]