“…Many targeted applications such as fluorescent labelling [19], drug delivery [20], and imaging for detecting biological species like virus, bacteria, cell, DNA, RNA molecules, or proteins [15,18,19] of new hybrid nanophosphors containing rare-earth elements (Eu, Tb, and Er) with various host materials (GdPO 4 , Gd 2 O 3 , YVO 4 , and NaYF 4 ) have been carried out so far [20][21][22][23][24][25]. For the synthesis of these materials, numerous chemical methods of luminescent nanomaterials containing rare earth elements have been used such as coprecipitation [5], sol-gel Pechini [6], and hydrothermal/solvothermal method [26][27][28][29]. Among these hybrid nanophosphors, Tb 3+ -doped GdPO 4 •nH 2 O nanomaterials are found to be one of the most promising candidates for these abovementioned applications due to these nanomaterials that exhibit strong luminescent intensity, paramagnetic behavior, no toxicity, and ability to minimize photobleaching and photochemical decomposition [22,23,[30][31][32][33].…”