Phosphor particle coating

A luminescent material comprising:

• a particulate luminescent material having a surface;
• a primer layer disposed on and in contact with the surface of the particulate luminescent material, the primer layer comprising a primer layer metal oxide and having a thickness in the range of 0.1-5 nm;
• a first ALD layer disposed on and in contact with the primer layer and any portion of the surface of the particulate luminescent material not covered with the primer layer, the first ALD layer comprising a first oxide of one or more of Al, Zn, Hf, Ta, Zr, Ti, Sn, Nb, Y, Ga, and V, and different from the primer layer metal oxide;
• a second ALD layer disposed on and in contact with the first ALD layer, the second ALD layer comprising a second oxide of one or more of Al, Zn, Hf, Ta, Zr, Ti, Sn, Nb, Y, Ga, and V, and different from the first oxide, the first ALD layer and second ALD layer forming a main ALD layer having a thickness in the range of 5-250 nm;
• and
• a main sol-gel coating layer disposed on the second ALD layer, wherein the main sol-gel coating has a main sol-gel coating layer thickness (d3) in the range of 50-700 nm, wherein the main sol-gel coating layer has a chemical composition differing from the first ALD layer and the second ALD layer.