Energy efficient microwave-assisted preparation of deep red/near-infrared emitting lithium aluminate and gallate phosphors

The development of impurity doped luminescent materials, or phosphors, have been continuously pursued for a variety applications nowadays. However, the majority phosphors undergo time-consuming and energy inefficient preparation, such as conventional high-temperature solid-state reaction (SSR). In present work, facile microwave-assisted (MASS) method is used to prepare series transition metal (Mn 4+ Cr 3+ ) lithium aluminates gallates. With one-step 25-min MASS method, LiAlO 2 obtained in ? phase rather than ? phase. Using same followed by short thermal treatment air two-step inverse spinel LiAl 5 O 8 :Mn with deep-red emission are obtained, while near-infrared emitting LiGa :Cr persistent successfully prepared 40-min process. Compared SSR achieved exhibits totally different trap depth distributions, which evidenced temperature dependency luminescence. study detailed preparation gallates may enable more widespread use facilitate exploration new luminescence properties involving defects. • Lithium energy-efficient fast synthesis (MASS). less suited intermediate phases. Trap structure strongly dependent on method.