학술논문

High Surface Area Assemblies of Gold Nanoparticles on Hydrophilic Carbon Fiber Paper with Ionomer Overlayers for Aqueous CO2 Reduction Electrocatalysis to Clean Syngas
Document Type
Original Paper
Source
Topics in Catalysis. 67(5-8):344-362
Subject
Electrocatalysis
Nanocatalyst
Carbon dioxide reduction
Carbon fiber paper
Syngas
Ionomer overlayers
Selectivity
Nafion
Sustainion
Microenvironment
Language
English
ISSN
1022-5528
1572-9028
Abstract
We report a universal approach for the utilization of nanoparticles on inexpensive, high surface area carbon substrates in aqueous applications. We immobilized gold nanoparticles from aqueous colloid on hydrophilic carbon fiber paper and assessed this electrode assembly in aqueous carbon dioxide reduction electrocatalysis. Uniform distributions of gold nanoparticles on carbon fibers and stable electrocatalytic current generation indicated that immobilization of gold nanoparticles on hydrophilic carbon fiber paper was successful. Surface analysis before and after electroreduction revealed that the detachment of citrate capping ligands enhanced the amount of exposed surface gold and concomitantly increased the CO-to-H2 ratio in subsequent CO2 reduction electrocatalysis. Systematic variations of ionomer overlayers controlled the ratio of produced CO and H2 towards useful syngas compositions and revealed mechanistic insights into catalyst microenvironments, to enhance CO selectivity. Our results demonstrate that hydrophilic carbon fiber paper is an excellent high surface area electrode substrate for the utilization of nanoparticulate electrocatalysts in aqueous electrolyte.