VNU Journal of Science Mathematics – Physics, Vol 37, No 3 (2021) 22 31 22 Original Article Photoluminescent Properties of Red emitting AlPO4 Cr 3+ Phosphor for Plant Growth LEDs Tran Manh Trung1, Nguyen Tu1,*, Nguyen Van Quang5, Do Quang Trung1, Pham Thanh Huy1,2 1Phenikaa University, Yen Nghia, Ha Dong, Hanoi, Vietnam 2Phenikaa Research and Technology Institute (PRATI), Phenikaa University, A&A Green Phoenix Group, 167 Hoang Ngan, Hanoi, Vietnam 3Hanoi Pedagogical University 2, Xuan Hoa, Vin[.]