Coordination engineering of cobalt phthalocyanine by functionalized carbon nanotube for efficient and highly stable carbon dioxide reduction at high current density

Abstract

Coordination engineering can enhance the activity and stability of the catalyst in heterogeneous catalysis. However, the axial coordination engineering between different groups on the carbon carrier and molecular catalysts in the electrocatalytic carbon dioxide reduction reaction (CO 2 RR) has been studied rarely. Through coordination engineering strategy, a series of amino (NH 2 ), hydroxyl (OH), and carboxyl (COOH) groups functionalized carbon nanotubes (CNT) immobilized cobalt phthalocyanine (CoPc) catalysts are designed. Compared with no groups, OH groups and COOH groups, NH 2 groups can effectively change the coordination environment of the central metal Co, thereby significantly increasing the turnover frequency (TOF) (31.4 s −1 at −0.6 V vs. RHE, CoPc/NH 2 -CNT > CoPc/OH-CNT > CoPc/COOH-CN > CoPc/CNT). In the flow cell, the CoPc/NH 2 -CNT catalyst has high carbon monoxide (CO) selectivity at high current density (~ 100% at −225 mA•cm −2 , ~ 96% at −351 mA•cm −2 ). Importantly, the CoPc/NH 2 -CNT catalyst can operate stably for 100 h at 225 mA•cm −2 . Theoretical calculations reveal that CoPc/NH 2 -CNT catalyst is beneficial to the formation of COOH and desorption of CO, thus promoting CO 2 RR. This work provides an excellent platform for understanding the effect of coordination engineering on electrocatalytic performance and promotes a way to explore efficient and stable catalysts in other applications.

Probing the Synergistic Effects of Mg2+ on CO2 Reduction Reaction on CoPc by In Situ Electrochemical Scanning Tunneling Microscopy

“…The electrochemical measurement shows the high stability of the CoPc-modified electrode during CO 2 RR. Apparent decay in catalytic activity is not observed after 6 h of electrocatalysis (Figure S1b), which is in accord with the previous reports. − …”

Constructing stable charge redistribution through strong metal–support interaction for overall water splitting in acidic solution

“…The peaks at 532.9 eV, 531.6 eV and 529.7 eV correspond to the lattice oxygen (Ru-O), oxygen vacancies, and surface-adsorbed hydroxyl or oxygen species, respectively, and the above results further indicate the existence of RuO 2 . 5,32 Moreover, for the Pt-RuO 2 @KB sample, the peak at 284.7 eV belonging to C-C shied to a higher position than that of KB (284.5 eV) (Fig. 1f).…”

High entropy stabilizing lattice oxygen participation of Ru- based oxides in acidic water oxidation

“…Electrocatalytic water splitting is a green and sustainable means of hydrogen and oxygen production that can effectively mitigate environmental and energy problems. [1][2][3][4][5][6][7][8] At the same time, proton exchange membrane water electrolysis (PEMWE) is a promising technology with the advantages of high current density and high product purity. [9][10][11][12][13][14] In addition, the compact structure of PEMs avoids the formation of contaminant carbonates in acidic media, which is why they are of great interest for acidic oxygen precipitation reactions.…”