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Title: Using Host‐Guest Chemistry to Examine the Effects of Porosity and Catalyst‐Support Interactions on CO 2 Reduction
Abstract Bis‐porphyrin nanocages (M2BiCage, M = FeCl, Co, Zn) and their host‐guest complexes with C60and C70were used to examine how molecular porosity and interactions with carbon nanomaterials affect the CO2reduction activity of metalloporphyrin electrocatalysts. The cages were found to adsorb on carbon black to provide electrocatalytic inks with excellent accessibilities of the metal sites (≈50%) even at high metal loadings (2500 nmol cm−2), enabling good activity for reducing CO2to CO. A complex of C70bound inside(FeCl)2BiCageachieves high current densities for CO formation at low overpotentials (|jCO| >7 mA cm−2,η= 320 mV; >13.5 mA cm−2,η= 520 mV) with ≥95% Faradaic efficiency (FECO), andCo2BiCageachieves high turnover frequencies (≈1300 h−1,η= 520 mV) with 90% FECO. In general, blocking the pore with C60or C70improves the catalytic performance of(FeCl)2BiCageand has only small effects onCo2BiCage, indicating that the good catalytic properties of the cages cannot be attributed to their internal pores. Neither enhanced electron transfer rates nor metal‐fullerene interactions appear to underlie the ability of C60/C70to improve the performance of(FeCl)2BiCage, in contrast to effects often proposed for other carbon nanosupports.  more » « less
Award ID(s):
2117792 2204045
PAR ID:
10581485
Author(s) / Creator(s):
; ; ; ; ; ; ;
Publisher / Repository:
German Chemical Society
Date Published:
Journal Name:
Angewandte Chemie International Edition
ISSN:
1433-7851
Subject(s) / Keyword(s):
C1 Building Blocks Catalysis Electrochemistry Porphyrinoids Supramolecular chemistry
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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