(198f) A Study of Asymmetry Cu-MOFs Electrode Prepared in situ and Its Biomimetic Catalysis

Zhipeng Li, Liwei Ren, Diannan Lu*

Department of Chemical Engineering, Tsinghua University, Beijing 100084, China

To whom it corresponds: ludiannan@tsinghua.edu.cn

Metal–organic frameworks (MOFs) are compounds consisting of metal center or clusters coordinate to organic ligands. MOFs have been widely used in almost essential fields like luminescence, catalysis, storage or separation of gases ^[1-3]. Traditional MOFs with symmetric structure are synthesized using hydrothermal method ^[4]. In this work, we in situ synthesized the asymmetric MOFs, Cu-bipy-BTC, on the surface of gold electrode directly. The structure of Cu-bipy-BTC MOFs on the electrode surface was characterized using FT-IR, XRD, SEM and EDS. It is shown that the newly in situ synthesized Cu-bipy-BTC MOFs have different active metal centers, which are located in different hydrophobic environment. More importantly, the MOFs exhibit flexible structure, which responses to the electric field applied on it. This flexible structure is very similar to that of active site of laccase ^[5], giving better catalytic activity. This MOFs electrode enables the catalytic oxidation of catechol at + 0.4 V(vs Ag/AgCl). The amperometric responses are linear with concentrations of catechol ranged from 10 to 250 µM and 250 to 1000 µM with the sensitivity of 1.6224 µA·cm^-2·µM^-1 and 0.2595 µA·cm^-2·µM^-1, respectively. Compared with other catechol electrochemical sensor, this asymmetric MOFs-based electrode has advantages of higher sensitive and easy-made, which has potential application in the detection of phenols.

Reference:

[1] Yao Q, Bermejo Gómez A, Su J, et al. Series of Highly Stable Isoreticular Lanthanide Metal–Organic Frameworks with Expanding Pore Size and Tunable Luminescent Properties[J]. Chemistry of Materials, 2015, 27(15): 5332-5339.

[2] Schlesinger M, Schulze S, Hietschold M, et al. Evaluation of synthetic methods for microporous metal–organic frameworks exemplified by the competitive formation of [Cu₂(btc)₃(H₂O)₃]and[Cu₂(btc)(OH)(H₂O)][J]. Microporous and Mesoporous Materials, 2010, 132(1): 121-127.

[3] Ren J, Musyoka N M, Langmi H W, et al. Hydrogen storage in Zr-fumarate MOF[J]. International Journal of Hydrogen Energy, 2015, 40(33): 10542-10546.

[4] Mao J, Yang L, Yu P, et al. Electrocatalytic four-electron reduction of oxygen with Copper (II)-based metal-organic frameworks[J]. Electrochemistry Communications, 2012, 19: 29-31.

[5] Song L F, Jiang C H, Jiao C L, et al. Two new metal− organic frameworks with mixed ligands of carboxylate and bipyridine: synthesis, crystal structure, and sensing for methanol[J]. Crystal Growth & Design, 2010, 10(12): 5020-5023.