The invention relates to acylhydrazone molecules capable of activating
solid-state
fluorescence or
photochromism and preparation and application thereof, in the molecular structure, by changing a
substituent R on a-N (R)-group on one side of benzoyl hydrazine, the conformation and accumulation mode of the molecules can be adjusted, so that selective activation of the
fluorescence or
photochromism property of the acylhydrazone molecules in a
solid state is realized. When the
substituent R is-H, the
molecular conformation is planar, and the intermolecular accumulation is tight. In a
solid state, the compound shows an
excitation wavelength dependent
fluorescence property, and when the
wavelength of excitation light is changed, the fluorescence color is switched between blue and green. When the
substituent R is-CH3, due to the steric effect of-CH3, the
molecular conformation is distorted, and the accumulation among molecules becomes more loose. When
ultraviolet light and visible light are alternately used for
irradiation in a short time, the color of the
powder can be rapidly switched between white and orange. The method provided by the invention is not influenced by R'on a
benzene ring, and shows good universality.