Investigation of sintering temperature and Ce3+ concentration in YAG:Ce phosphor powder prepared by microwave combustion for white-light-emitting diode luminance applications

YAG:Ce3+ Phosphor: From Micron-Sized Workhorse for General Lighting to a Bright Future on the Nanoscale

“…The latter dries the sol in the microwave oven at 900W, leading to formation of many fumes and subsequent ignition. The product formed is reheated in a conventional oven, where a temperature of 950 °C for 5 h is needed to obtain phase pure YAG particles and results in particle dimensions >100 nm (Figure I) …”

“…The resulting particles are either sintered structures ,,,,− ,,,,,, (H) or large crystals ,, (I), depending on the calcination conditions used. Only when protective matrices are used during the calcination, individual nanocrystals are formed. , Starting from a sol–gel synthesis, the YAG precursor is first combusted − (sometimes in a microwave oven − ) and then calcined in an oven. The matrix approach made use of an oven, without separate combustion step .…”

“…The matrix approach made use of an oven, without separate combustion step . The resulting particles are either large crystals ,,, or sintered materials. − ,, The solvothermal procedure is a one-step synthesis to yield either agglomerated − or individual nanocrystals. ,− One paper reports subsequent calcining in a matrix, yielding large crystals …”

“…(I) YAG particles first treated in a microwave oven, then calcined at 950 °C. Reprinted (adapted) with permission from refs (panels A–D, Copyright 2003 Elsevier), (panel F, Copyright 2004 Elsevier), (panel G, Copyright 2004 The Royal Society of Chemistry), (panel H, Copyright 2009 Elsevier), and (panel I, Copyright 2019 Elsevier).…”

“…Calcination using alternative equipment was reported by Vaidhyanathan et al and the group of Ahmed, , who used a microwave oven for this step of the reaction. The first paper reports preparation of a dried gel from NO 3 salts and nitric acid and subsequent heating of this product in a 2.45 GHz microwave oven at 1 kW, obtaining temperatures of 500 to 1000 °C.…”