“…[6][7][8] In the past years, chromium-activated ZnGa 2 O 4 is being considered as one of the most fascinating optical materials due to its outstanding and bright near-infrared photoluminescence, efficient persistent luminescence, long afterglow, high light harvesting efficiency, wavelength tunability, and superior photostability. 2,3,[9][10][11][12][13] Consequently, ZnGa 2 O 4 :Cr 3+ (ZGOC) has found wide range applications in areas such as bioimaging, optical sensors, optical information storage, drug delivery, and plant growth. 2,9,10,13,14 However, there is still continuous ongoing effort in the global research community to explore more functionalities, add new dimensions, and improve the optical properties of ZGOC nanoparticles.…”