A general concept for white light emission formation from two complementary colored luminescent dyes

White-light emitting materials have attracted extensive research interest in recent years, which is largely ascribed to their potential applications in lighting devices and display media. Scientists have reported that organic white-light emitters mostly depend on the integration of several components that simultaneously emit different colors of light. However, it is a challenge to rationally tune the ratios of colored luminescent dyes to produce white-light emitting materials since we still cannot find the general principles to guide their preparation. In this paper, we demonstrate that “equal is important”, which means that once the emission intensities from two complementary colored luminescent dyes are equally maintained, white light emission can be generated in a range of states, including in solids, solutions, and gels. During the research process, we also found that cationic fluorescent cores are highly sensitive to the polarity of solvents. Therefore, our results could inform the design of visual indicators for the polarity and electrical conductivity of solvents using fluorescence signals.