Bulk ceramics of lanthanum hexaboride with enhanced spectral selectivity and photothermal efficiency for novel hybrid thermal-thermionic solar absorbers
Year: 2024
Authors: Sani E., Sciti D., Failla S., Bellucci A., Mastellone M., Orlando S., Trucchi DM.
Autors Affiliation: CNR, INO, Largo E Fermi 6, I-50125 Florence, Italy; CNR, Inst Sci Technol & Sustainabil Ceram, Via Granarolo 64, I-48018 Faenza, Italy; CNR, ISM, Montelibretti Sect, Via Salaria Km 29-300, I-00015 Rome, Italy; CNR, ISM, Tito Scalo Sect, Zona Ind, I-85050 Tito, PZ, Italy.
Abstract: Lanthanum hexaboride (LaB6) single-crystals are known from a long time for their excellent thermionic and fieldassisted electron-emitting properties. Recently, multi-crystalline ceramics, which offer several technological advantages over single-crystals, have been studied as well, proving a low work function and Richardson constant, in addition to favorable optical properties for high-temperature solar radiation absorbers. However, to fully disclose to LaB6 ceramics the novel application of a double-function bulk thermionic emitter, enabled by the direct absorption of solar radiation, and, at the same time, thermodynamic solar absorber for Concentrating Solar Power (CSP), their optical properties should be further optimized. The ideal result, consisting in the selective increase of the solar absorptance and decrease of the thermal emittance, thus increasing both the spectral selectivity and the photothermal efficiency of the absorber, has been obtained in this work by realizing LaserInduced Periodic Surface Structures (LIPSS) on the ceramic surface by means of femtosecond-laser treatments. LIPPS formation has been investigated as a function of the accumulated laser fluence.
Journal/Review: SOLAR ENERGY
Volume: 271 Pages from: 112423-1 to: 112423-8
More Information: This study was partially developed in the framework of the research activities carried out within the Project Network 4 Energy Sustainable Transition-NEST, Spoke 1, Project code PE0000021, funded under the National Recovery and Resilience Plan (NRRP) , Mission 4, Component 2, Investment 1.3- Call for tender No. 1561 of 11.10.2022 of Ministero dell’Universita’e della Ricerca (MUR) ; funded by the European Union- -NextGenerationEU. The CNR-INO technicians Mauro Pucci and Massimo D’Uva are acknowledged for technical support, as well as CNR-INO administration staff Francesca Usala, Pasqualina Pipino and Roberta Parenti.KeyWords: Surface texturing; Solar absorbers; Concentrated solar radiation; Solar-to-electric conversion; Spectrally selective solar absorbers; High temperatureDOI: 10.1016/j.solener.2024.112423Connecting to view paper tab on IsiWeb: Click here