Institution: | 1. Fujian Provincial Key Laboratory of Polymer Materials, College of Chemistry and Materials Science, Fujian Normal University, 350117 Fuzhou, China
These authors contributed equally to this work.;2. Fujian Provincial Key Laboratory of Polymer Materials, College of Chemistry and Materials Science, Fujian Normal University, 350117 Fuzhou, China;3. Xiamen Key Laboratory of Rare Earth Photoelectric Functional Materials, Xiamen Institute of Rare Earth Materials, Haixi Institute, Chinese Academy of Sciences, Xiamen, 361000 China |
Abstract: | Rational design of crystalline porous materials with coupled proton-electron transfer has not yet been reported to date. Herein, we report a donor-acceptor (D-A) π-π stacking hydrogen-bonded organic framework (HOF; HOF-FJU-36 ) with zwitterionic 1,1′-bis(3-carboxybenzyl)-4,4′-bipyridinium (H2L2+) as acceptor and 2,7-naphthalene disulfonate (NDS2?) as donor to form a two-dimensional (2D) layer. Three water molecules were situated in the channels to connect with acidic species through hydrogen bonding interactions to give a 3D framework. The continuous π-π interactions along the a axis and the smooth H-bonding chain along the b axis provide the electron and proton transfer pathways, respectively. After 405 nm light irradiation, the photogenerated radicals could simultaneously endow HOF-FJU-36 with photoswitchable electron and proton conductivity due to coupled electron-proton transfer. By single-crystal X-ray diffraction (SCXRD) analyses, X-ray photoelectron spectroscopy (XPS), transient absorption spectra and density functional theory (DFT) calculations, the mechanism of the switchable conductivity upon irradiation has been demonstrated. |