A Covalent Organic Framework Film for Three‐State Near‐Infrared Electrochromism and a Molecular Logic Gate

• Published in: Angewandte Chemie International Edition Vol. 60; no. 22; pp. 12498 - 12503
• Main Authors: Hao, Qing, Li, Zhi‐Juan, Bai, Bin, Zhang, Xing, Zhong, Yu‐Wu, Wan, Li‐Jun, Wang, Dong
• Format: Journal Article
• Language: English
• Published: Germany Wiley Subscription Services, Inc 25.05.2021
• Edition: International ed. in English
• Subjects: Absorption spectra; Bleaching; Charge transfer; covalent organic frameworks; Electrochromism; Logic circuits; logic gates; Mimicry; Molecular structure; Near infrared radiation; near-infrared electrochromism; optical memory; Optical memory (data storage); Response time; Retention time; near-infrared electrochromism; covalent organic frameworks; logic gates; optical memory
• ISSN: 1433-7851; 1521-3773; 1521-3773
• DOI: 10.1002/anie.202100870

A Kagome structure covalent organic framework (COF) film with three‐state NIR electrochromic properties was designed and synthesized. The COFTPDA‐PDA film is composed of hexagonal nanosheets with high crystallinity and has three reversible color states at different applied potentials. It has high absorption spectra changes in the NIR region, ascribed to the strong intervalence charge transfer (IVCT) interaction of the Class III mixed‐valence systems of the conjugated triphenylamine species. The film showed sub‐second response time (1.3 s for coloring and 0.7 s for bleaching at 1050 nm) and long retention time in the NIR region. COFTPDA‐PDA film shows superior NIR electrochromic properties in term of response time and stability, attributed to the highly ordered porous structure and the π–π stacking structure of the COFTPDA‐PDA architecture. The COFTPDA‐PDA film was applied in mimicking a flip‐flop logic gate with optical memory function. A Kagome structure covalent organic framework (COF) film was synthesized and exhibited three‐state electrochromic properties with sub‐second response time and long retention time in the near‐infrared region. Taking potential and absorbance as input and output signal, respectively, a mimicking logic gate with optical memory functions was demonstrated based on the COFTPDA‐PDA film.