The chemical-physical properties of thin lanthanum (oxy)boride films deposited on polycrystalline tantalum substrates by different deposition techniques (Pulsed Laser Deposition - PLD - with either nanosecond or femtosecond laser source, and electron beam evaporation) were compared in order to investigate the effect of chemical composition, crystallinity, surface morphology of the thin films on the thermionic electron emission capability. The emission performance of the films was analyzed in the 700–1600 °C temperature range, allowing the determination of work function values ranging from 2.59 to 2.85 eV and an effective Richardson constant at least one order of magnitude lower than the ideal value for all the films. The highest measured thermionic current density value of 1.68 A/cm 2 at 1600 °C was provided by the samples grown by femtosecond PLD, indicating a promising performance for practical application in high-temperature thermal-to-electric energy conversion.

Lanthanum (oxy)boride thin films for thermionic emission applications / Bellucci, A.; Mastellone, M.; Orlando, S.; Girolami, M.; Generosi, A.; Paci, B.; Soltani, P.; Mezzi, A.; Kaciulis, S.; Polini, R.; Trucchi, D. M.. - In: APPLIED SURFACE SCIENCE. - ISSN 0169-4332. - 479:(2019), pp. 296-302. [10.1016/j.apsusc.2019.01.230]

Lanthanum (oxy)boride thin films for thermionic emission applications

Mastellone M.;
2019

Abstract

The chemical-physical properties of thin lanthanum (oxy)boride films deposited on polycrystalline tantalum substrates by different deposition techniques (Pulsed Laser Deposition - PLD - with either nanosecond or femtosecond laser source, and electron beam evaporation) were compared in order to investigate the effect of chemical composition, crystallinity, surface morphology of the thin films on the thermionic electron emission capability. The emission performance of the films was analyzed in the 700–1600 °C temperature range, allowing the determination of work function values ranging from 2.59 to 2.85 eV and an effective Richardson constant at least one order of magnitude lower than the ideal value for all the films. The highest measured thermionic current density value of 1.68 A/cm 2 at 1600 °C was provided by the samples grown by femtosecond PLD, indicating a promising performance for practical application in high-temperature thermal-to-electric energy conversion.
Electron beam evaporation; Lanthanum borides; Low work function; Pulsed Laser Deposition; Thermionic emission
01 Pubblicazione su rivista::01a Articolo in rivista
Lanthanum (oxy)boride thin films for thermionic emission applications / Bellucci, A.; Mastellone, M.; Orlando, S.; Girolami, M.; Generosi, A.; Paci, B.; Soltani, P.; Mezzi, A.; Kaciulis, S.; Polini, R.; Trucchi, D. M.. - In: APPLIED SURFACE SCIENCE. - ISSN 0169-4332. - 479:(2019), pp. 296-302. [10.1016/j.apsusc.2019.01.230]
File allegati a questo prodotto
File Dimensione Formato  
1-s2.0-S0169433219302612-main.pdf

solo gestori archivio

Tipologia: Versione editoriale (versione pubblicata con il layout dell'editore)
Licenza: Tutti i diritti riservati (All rights reserved)
Dimensione 1.31 MB
Formato Adobe PDF
1.31 MB Adobe PDF   Visualizza/Apri   Richiedi una copia

I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.

Utilizza questo identificativo per citare o creare un link a questo documento: https://hdl.handle.net/11573/1341229
Citazioni
  • ???jsp.display-item.citation.pmc??? ND
  • Scopus 12
  • ???jsp.display-item.citation.isi??? 10
social impact