The poor durability of Pt-based nanoparticles dispersed on carbon
black is the challenge for the application of long-life polymer electrolyte
fuel cells. Recent work suggests that Fe- and N-codoped carbon (Fe–N–C)
might be a better support than conventional high-surface-area carbon.
In this work, we find that the electrochemical surface area retention
of Pt/Fe–N–C is much better than that of commercial
Pt/C during potential cycling in both acidic and basic media. In situ inductively coupled plasma mass spectrometry studies
indicate that the Pt dissolution rate of Pt/Fe–N–C is
3 times smaller than that of Pt/C during cycling. Density functional
theory calculations further illustrate that the Fe–N–C
substrate can provide strong and stable support to the Pt nanoparticles
and alleviate the oxide formation by adjusting the electronic structure.
The strong metal–substrate interaction, together with a lower
metal dissolution rate and highly stable support, may be the reason
for the significantly enhanced stability of Pt/Fe–N–C.
This finding highlights the importance of carbon support selection
to achieve a more durable Pt-based electrocatalyst for fuel cells.
The electrochemical reduction reaction of carbon dioxide (CO2RR) is considered to be an effective way to realize carbon neutrality. As a type of intensively studied materials, covalent organic frameworks (COFs) with a tunable pore structure and various functional groups are promising catalysts for CO2RR. Herein, COF synthesized by 2,6‐diaminoanthraquinone and 2,4,6‐triformylphloroglucinol is employed to assist the synthesis of electrocatalysts from Cu single atoms (SAs) to nanoclusters by controlling the electrodeposition. A tandem catalyst for CO2‐to‐CH4 conversion is thus achieved by the Cu nanoclusters dispersed among the isolated Cu SAs in the COF network. It is proposed that CO2 is first reduced to CO over the atomically isolated Cu SAs, followed by diffusion onto the neighboring Cu nanoclusters for further reduction into CH4. In addition, mechanistic analysis suggests that the coordinated K+ ions on the COF network promote the activation of CO2 and the adsorption of reaction intermediates, thus realizing the suppressed hydrogen evolution reaction and selective production of CH4. This study presents a new insight of COFs for the confined synthesis of a tunable SA to nanocluster electrocatalysts, disclosing the great potential of COFs in electrocatalysis.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.