A molecular keypad lock with 3-output signals built on stimulus-responsive polymer film electrodes containing diallyl viologen. (20th February 2022)

• Record Type: Journal Article
• Authors: Wei, Wenting; Li, Jiaxuan; Yao, Huiqin; Liu, Hongyun
• Is Part Of: Electrochimica acta. Volume 406(2022)
• Publication Date: 2022-02-20
• Subjects: Molecular logic gates -- Electrochemical catalysis -- Viologen derivatives -- Electrochromism -- Keypad lock; Electrochemistry -- Periodicals; Electrochemistry, Industrial -- Periodicals; 541.37
• DOI: 10.1016/j.electacta.2022.139839
• Languages: English
• ISSNs: 0013-4686

Abstract

Highlights: A viologen derivative DAV was immobilized at electrochromic polymer film electrodes by one-step. A computing platform was constructed with DAV as the calculation core. A resettable and reprogrammable keypad lock with 3 different output signals was built. Abstract: Herein, by a one-step synthetization method, a viologen derivative diallyl viologen (DAV) was first polymerized with methacryloylglycine (MAG) into P(MAG-DAV) polymer films on the surface of ITO electrodes. DAV component in the P(MAG-DAV) films was used not only as a cross-linker and immobilized in the film phase for repetitive usages, but also demonstrated reversibly electrochromic and luminescent properties. When the electrode voltage was switched between −0.7 and −0.5 V (vs SCE), DAV could transfer from its purple reduction state (DAV + ) to colorless oxidation state (DAV 2+ ) through the electrode reactions, accompanied with the fluorescence signal switching between non-fluorescence (DAV + ) and green fluorescence (DAV 2+ ) states. The addition of KMnO4 in the solution could oxidize DAV + to its DAV 2+ form in the films to generate electrocatalytic signals and change the optical signals at the same time. Based on various reversible stimulus-responsive behaviors of P(MAG-DAV) film electrodes, a logic system of 3-input/3-output was established using potential, KMnO4 and ultraviolet excitation light as inputs, and cyclic voltammetry (CV), fluorescence (FL) and UV−vis signals as outputs. Including an encoder and a decoder, a unique resettable and reprogrammable keypad lock was built with 3 different outputs. The system used a single immobilized molecule as the core of computing, and applied only 3 stimuli as inputs to construct an integrated logic computing system with 3 different output signals, which greatly improved the complexity and diversity of the molecular computing system. This might provide a new idea for the subsequent development of multifunctional integrated logic devices. Graphical abstract: A resettable and reprogrammable keypad lock was constructed based on the redox, electrochromic and fluorescent properties of a viologen derivative immobilized in the films. Image, graphical abstract