Thermal-stable blue-red dual-emitting Na2Mg2Si6O15: Eu2+, Mn2+ phosphor for plant growth lighting

Dual-emitting alkaline silicate phosphors Na2Mg2Si6O15: Eu2+, Mn2+ have been synthesized to realize blue and red emissions to boost photosynthesis process. At UV excitation, Na2Mg2Si6O15: Eu2+, Mn2+ phosphors exhibit efficient blue and red emissions due to Eu2+ 4f-5d transition and Mn2+ 3d-3d transition, which matches well with the absorption of plant chlorophylls, and also could be excited by near ultraviolet LED chip. The emitting color could be readily tuned from blue through pink to red due to effective Eu2+-Mn2+ energy transfer by changing Eu2+/Mn2+ ratio. And the corresponding energy transfer mechanism is found to be dipole-dipole interaction. The thermal stability of Na2Mg2Si6O15: Eu2+, Mn2+ is significantly higher than that of most reported Eu2+, Mn2+ co-activated dual-emitting phosphors, due to thermally activated defect-Eu2+-Mn2+ energy transfer process. Thus, it indicates that Na2Mg2Si6O15: Eu2+, Mn2+ is of great potential as converted phosphors for plant growth application.