Near-infrared emitting Ca 5 (PO 4 ) 3 Cl:Eu 2+ ,Nd 3+ phosphor for modification of the solar spectrum

• Published in: Luminescence (Chichester, England) Vol. 33; no. 7; pp. 1288 - 1293
• Main Authors: Tawalare, P K, Bhatkar, V B, Omanwar, S K, Moharil, S V
• Format: Journal Article
• Language: English
• Published: England 01.11.2018
• Subjects: Energy Transfer; Europium - chemistry; Infrared Rays; Luminescence; Luminescent Agents - chemical synthesis; Luminescent Agents - chemistry; Luminescent Measurements; Neodymium - chemistry; Solid-Phase Synthesis Techniques; X-Ray Diffraction; solar photovoltaics; Eu2+→Nd3+ energy transfer; neodymium; photoluminescence; near-infrared
• ISSN: 1522-7235; 1522-7243
• DOI: 10.1002/bio.3548

Intense near-infrared (NIR) emitting phosphors Ca (PO ) Cl:Eu ,Nd were synthesized using a conventional solid-state reaction method and characterized using X-ray diffraction, reflectance, photoluminescence (PL) emission and PL excitation (PLE) spectroscopy, and PL lifetime measurements. The emission could be excited by broad band radiation in the nUV region as a consequence of Eu →Nd energy transfer. The efficiency of Eu →Nd energy transfer was as high as 80.8%. Two components observed in the decay curves could be identified with Eu substituting different Ca sites. Eu lifetimes were shortened after Nd doping. Near infra-red emission intensity was limited by Nd →Nd energy transfer and the consequent concentration quenching. The critical distance for Nd →Nd energy transfer was estimated to be 11.41 Å. Absorption of nUV radiations followed by conversion to NIR indicated the potential application in solar photovoltaics.