White light emitting materials can not only meet people's daily lighting needs, but also have important applications in different fields such as multi-color display, imaging, anti-counterfeiting, visible light transmission and so on, so it has become one of the research hotspots in recent years.

White light emission can be obtained from multi-color emitting materials, usually composed of two complementary colors (blue and yellow) or three optical primary colors (red, green and blue). Dye @MOF material system with controllable composition can be obtained by utilizing the unique pore structure of metal-organic framework (MOF) and adsorbing organic dyes through the interaction between host and guest. In addition, by using the luminescent combination of MOF host and dye guest, the composition ratio, excitation wavelength and energy transfer between host and guest can be adjusted to obtain multi-color luminescence and white light emission. However, the idea of using dye @MOF system to obtain combined white light is mostly limited to the single photon path excited by ultraviolet light.

Recently, Pan Mei Research Group of Sun Yat-sen University has successfully obtained the dye @MOF white light material system with two-way photon conversion by using the single-photon process excited by ultraviolet light and the two-photon process excited by near-infrared light.