Conductive phthalocyanine-based metal-organic framework as a highly efficient electrocatalyst for carbon dioxide reduction reaction

• Published in: Science China. Chemistry Vol. 64; no. 8; pp. 1332 - 1339
• Main Authors: Zhang, Meng-Di, Si, Duan-Hui, Yi, Jun-Dong, Yin, Qi, Huang, Yuan-Biao, Cao, Rong
• Format: Journal Article
• Language: English
• Published: Beijing Science China Press 01.08.2021; Springer Nature B.V
• Subjects: Carbon dioxide; Chemical reduction; Chemistry; Chemistry and Materials Science; Chemistry/Food Science; Conjugation; Current density; Density functional theory; Electrical resistivity; Electrocatalysts; Electrode materials; Low currents; Metal-organic frameworks; Nickel; Phenylenediamine; Porous materials; electroreduction; CO; conductive; metal-organic frameworks
• ISSN: 1674-7291; 1869-1870
• DOI: 10.1007/s11426-021-1022-3

Porous crystalline metal-organic frameworks (MOFs) are one class of promising electrode materials for CO 2 electroreduction reaction (CO 2 RR) by virtue of their large CO 2 adsorption capacities and abundant tunable active sites, but their insulating nature usually leads to low current density. Herein, a two-dimensional (2D) Ni-phthalocyanine-based MOF (NiPc-Ni(NH) 4 ) constructed by 2,3,9,10,16,17,23,24-octaaminophthalocyaninato nickel(II) (NiPc-(NH 2 ) 8 ) and nickel(II) ions attained high electrical conductivity due to the high overlap of d-π conjugation orbitals between the nickel node and the Ni-phthalocyanine-substituted o -phenylenediamine. During CO 2 RR, the NiPc-Ni(NH) 4 nanosheets achieved a high CO Faradaic efficiency of 96.4% at −0.7 V and a large CO partial current density of 24.8 mA cm −2 at −1.1 V, which surpassed all the reported two-dimensional MOF electrocatalysts evaluated in an H-cell. The control experiments and density functional theory (DFT) calculations suggested that the Ni-N 4 units of the phthalocyanine ring are the catalytic active sites. This work provides a new route to the design of highly efficient porous framework materials for the enhanced electrocatalysis via improving electrical conductivity.