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ZnOS phosphors were synthesized by a two-step high-temperature solid-phase method. The as-synthesized CaS:Eu 2+ ,Pb 2+ @Ca-ZnOS:Pb 2+ phosphors possess excellent dual-excitation and dualemission (DE 2 ) luminescent properties, which give rise to red emission peaking at 650 nm under green excitation, derived from the core CaS:Eu 2+ ,Pb 2+ , and blue emission peaking at 424 nm, originating from the shell CaZnOS:Pb 2+ , under ultraviolet (UV) excitation. In addition, tunable red/blue emission can be achieved by changing the doping concentration of Pb 2+ in the CaZnOS shell. The red/blue dual emission of core−shell DE 2 phosphors under excitation of UV and green light significantly matches with the absorption spectrum of chlorophyll (a, b); hence, the as-prepared phosphors are excellent solar spectral conversion (SSC) auxiliaries of plastic films or laminated glass for greenhouses and provide ideas for creating more efficient and practically valuable SSC auxiliaries. The DE 2 properties are described, and the energy transfer mechanism from Pb 2+ to Eu 2+ in the core is proposed and discussed in detail.

As a universal sunlight-conversion agent for agricultural shed films, the green-to-red phosphor CaS:Eu 2+ suffers greatly from its poor moisture resistance. Unlike the conventional surface modifications upon application of postprocessing, this work proposes a one-step, two-additive strategy for synthesizing the CaS:Eu 2+ ,CaBr 2 ,CaF 2 composite phosphor. For the first time, we realize remarkable improvements in both the chemical stability and the luminescence intensity of a CaS:Eu 2+ -based material synchronously. The dual halide-modified composite phosphor maintains a stable phase composition against moist air and water immersion. The red emission of the as-obtained CaS:Eu 2+ ,CaBr 2 ,CaF 2 phosphor becomes 3 times as intense as that of nonmodified CaS:Eu 2+ . Moreover, the polymer film fabricated with the modified phosphor presents good weather resistance and brilliant lightconversion performance. Therefore, this one-step method gives the CaS:Eu 2+ ,CaBr 2 ,CaF 2 phosphor a great advantage as a long life light-conversion material for agricultural shed films.