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Developing optical anti-counterfeiting technology with dynamic color changes offers new hope for improving the replication difficulty of anti-counterfeiting labels and promoting the updating and iteration of high-level security technology and information encryption, but remains a huge challenge. Herein, we develop a ground-breaking multi-wavelength excitation-dependent anti-counterfeiting technology based on security inks containing three luminescent materials that respond to 254 nm, 365 nm, and 980 nm excitation, respectively. A blue carbon dots/calcium carbonate (B-CDs/CaCO3) composite and a green carbon dots/silicon dioxide (G-CDs/SiO2) composite are prepared via in situ loading processes. The former exhibits blue fluorescence (FL) emission light and green room-temperature phosphorescence (RTP) when turning on/off 365 nm excitation, and the latter emits green FL under the same conditions. Under 254 nm excitation, excellent red emission is realized in the YVO4:Eu3+ (R-Eu) phosphor. Blue and green upconversion luminescence (UCL) are obtained in YVO4:Tm3+/Yb3+ and YVO4:Er3+/Yb3+ phosphors upon 980 nm excitation. When integrating these luminescent materials into invisible security inks, the printed security patterns exhibit triple-mode polychromatic information and spatial dynamic color-gradient characteristics by varying the excitation conditions (wavelength, intensity, illumination angle, and exposure time of excitation light). The unique optical properties enable the resulting security labels to show a high-level anti-counterfeiting strength and demonstrate application value in next-generation anti-counterfeiting. [ABSTRACT FROM AUTHOR]

Constructing a library of stable phosphors with unconventional fluorescence (FL) and room temperature phosphorescence (RTP) color combination is an effective approach to enhance anti‐counterfeiting strength, but remains a challenge. Herein, a one‐step strategy is proposed to fabricate ultra‐stable CsPbX3/carbon dots (CDs) @NH4AlP2O7 (X = Cl, Br, and I) nanocomposites (PCPNs) with full‐spectrum FL emission and constant short‐wavelength blue RTP emission, breaking the conventional luminescent properties that RTP generally exhibit obvious wavelength red‐shifts compared with FL. The enhanced full‐color (457–612 nm) FL emissions are implemented by adjusting halogen compositions, which is attributed to CsPbX3 as the dominant FL center. Owing to the RTP emission of CDs, constant long‐lived blue RTP emission lasting 12 s is observed from PCPNs. Additionally, the PCPNs exhibit remarkable tolerance to prolonged ultraviolet irradiation and erosion by solutions with various pH and solvents, supported by NH4AlP2O7 inert shell stabilizing the perovskite structure and triplet state. When the anti‐counterfeiting ink based on PCPNs is printed on various substrates, fine anti‐counterfeiting labels with unconventional emission combinations of FL and RTP are formed and show excellent solvent resistance and mechanical stability. This study provides fresh perspectives on the development of anti‐counterfeiting labels with enhanced security strength and long‐term effects. [ABSTRACT FROM AUTHOR]