Dual-Optical Signal Molecular Logic System Based on CsPbBr₃@SiO₂ Film Electrodes with Modulated Photoluminescence and Electrochemiluminescence Behaviors

In this study, metal halide perovskites, which are excellent materials for optoelectronic devices, were examined to construct molecular logic gates. The photoluminescence (PL) and electrochemiluminescence (ECL) properties of the CsPbBr₃ nanocrystals (NCs) were effectively maintained in the CsPbBr₃@SiO₂ NC films; these films were simply prepared by depositing nanocrystals on the electrode surface through the viscosity of SiO₂ in the coating. The dual-optical signals of the films were found to have different responses to the external stimuli of Fe­(III) and dopamine (DA). The PL signal of the films was quenched by Fe­(III), and this effect was exacerbated at a high concentration of DA due to the formation of oxidation products. However, the addition of ascorbic acid (AA) could restore the PL signal. While the ECL signal of the films did not show evident changes with the concentration of Fe­(III), the ECL signals quenched by a low concentration of DA could be reverted by Fe­(III). Thus, a multiple input–output molecular logic circuit based on the CsPbBr₃@SiO₂ film electrode system was constructed by using Fe­(III), DA, and AA as 3 inputs and the PL and ECL at different states as 6 outputs. A series of logic circuits, including an encoder/decoder, a dual transfer gate, a parity checker, a demultiplexer, and a resettable keypad lock, were successfully simulated. Specifically, a ternary CONSENSUS logic gate with a dual-optical signal output was initially mimicked based on this film electrode. This work could provide a simple approach to design a molecular information system based on the modulated multioptical signals of perovskites and could further expand the potential applications of perovskites in multiple-molecule recognition, chemical information storage, and optoelectronic devices.