CAO Ting, LIU LijianCollege of Chemistry and Molecular Sciences, Wuhan University, Wuhan 430072, Hubei, China
Conventionally, each fluorophore is only clarified with the wavelength of incident beam shorter (down-conversion) or longer (up-conversion) than that of emission light. However, three anthracenes presented in this paper are the wave-length-focused (WF) molecules which can shift the portions of shorter and longer wavelengths of incident light into an identical wavelength in between. UV (ultraviolet) and NIR (near infrared) portions of Xenon light-simulated solar spectrum are focused into visible light with maximum wavelengths ranging from 415 to 471 nm through the two-way photoluminescence of the three anthracenes (anthracene (AN), fluoranthene (FLA) and 9, 10-diphenylanthracene (DPA)). At the same time, the intensity of the visible light is two times as that of excitation light. Besides, DPA dissolved in different solvents shows excellent fluorescence features. The results present great potential for applications in enhancing the intensity of solar spectrum at visible region and utilizing more portions of sunlight with solar cell.
Key words:focusing; solar spectrum; two-way conversion; anthracene
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