Innovative technologies are highly pursued for the detection and avoidance of counterfeiting in modern information society. Herein, we report the construction of photo-responsive supramolecular polymers toward fluorescent anti-counterfeit applications, by taking advantage of multicycle anthracene‒endoperoxide switching properties. Due to σ-metalation effect, photo-oxygenation of anthracene to endoperoxide is proceeded under the mild visible light irradiation conditions, while the backward conversion occurs spontaneously at room temperature. Supramolecular polymers are formed with cooperative nucleation‒elongation mechanism, which facilitate fluorescence resonance energy transfer process via two-component co-assembly strategy. Fluorescence resonance energy transfer efficiency is delicately regulated by either light-triggered anthracene‒endoperoxide conversion or vapor-induced monomer–polymer transition, leading to high-contrast fluorescent changes among three different states. On this basis, dual-mode anti-counterfeiting patterns have been successfully fabricated via inkjet printing techniques. Hence, cooperative supramolecular polymerization of photo-fluorochromic molecules represents an efficient approach toward high-performance anti-counterfeit materials with enhanced security reliability, fast response, and ease of operation.

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Scanning electrochemical microscopy was used to probe the influence of a driving force on the heterogeneous electron transfer (ET) processes at the externally polarized water/1,2-dichloroethane interface. Being a part of the driving force, the Galvani potential difference at the interface, Deltaowphi, can be quantitatively controlled in a wide range, allowing the precise measurements of the rate constants of the ET reactions. Two opposite systems were chosen in this work. One was 5,10,15,20-tetraphenyl 21H,23H-porphyrin zinc (ZnPor, O)/Fe(CN)64- (W), and the other was TCNQ (O)/Fe(CN)63- (W). For both systems studied, the relations between the rate constant and the Deltaowphi were of parabolic shape; that is, the rate constants increased initially with the Deltaowphi until reaching a maximum and then decreased steadily as the Deltaowphi increased further. This is in accordance with the prediction of the Marcus theory. To our knowledge, this is the first report that the Marcus inverted region can be observed electrochemically at an unmodified liquid/liquid interface with only one redox couple at each phase. The effect of the concentrations of the organic supporting electrolyte has also been discussed in detail.