Active site engineering of single-atom carbonaceous electrocatalysts for the oxygen reduction reaction

Abstract

This Perspective summarizes and highlights the recent progress and milestones relating to the active site engineering of single atom carbonous electrocatalysts for enhancing the electrocatalytic oxygen reduction reaction activity.

Highly accessible and dense surface single metal FeN4 active sites for promoting the oxygen reduction reaction

“…29–31 By careful optimization of Fe- and N-containing precursor combinations and thermal treatments, the loading amount of single Fe in the current Fe–N–C electrocatalysts could reach as high as 3.0 wt%. 32–34 However, a large number of FeN 4 sites encased in the carbon substrate still remained inactive for the ORR process due to their inaccessibility. Meanwhile, the adsorption strengths of ORR intermediates ( i.e.…”

Experimental correlation of Mn3+cation defects and electrocatalytic activity of α-MnO2– an X-ray photoelectron spectroscopy study

“…This not only opens up new perspectives in the eld of electrocatalysis, but also complementary strategies in the eld of surface active site/defect engineering of porous catalyst materials for tuning electrocatalytic activities. [182][183][184][185] Moreover, through considering an inner and outer ECSA, a novel opportunity for determining intrinsic activities is provided and can be considered an innovative approach for establishing reasonable structure-activity relationships. A normalization by different ECSA constituents in turn will facilitate a straightforward identication and comprehension of potential catalytically active sites nally guiding the further development and exploration of highly active ORR electrocatalysts for a variety of energy conversion and storage applications such as fuel cells and metal-air batteries.…”

Descriptors and graphical construction forin silicodesign of efficient and selective single atom catalysts for the eNRR

“…12,13 We aim to mitigate these problems by appropriately tuning the electronic structure by altering the environment surrounding metal atoms at the active site of single atom catalysts (SACs). [14][15][16][17][18][19][20] In contrast to many previously studied SACs where the metal atom was adsorbed over a suitably modied two-dimensional (2D) support, [21][22][23][24][25] in our systems the metal atom is embedded within the 2D layer. [26][27][28][29] Moreover, in previous work, typically only one criterion (usually the competing HER) was used to optimize catalyst function, [30][31][32][33][34][35][36][37][38] whereas we will simultaneously optimize with respect to multiple criteria.…”

“…Transition metals are popular eNRR catalysts, however they tend to favor hydrogen adsorption due to the formation of strong metal d -hydrogen σ bonds, and also tend to have low affinity for N2 adsorption 12,13 . We aim to mitigate these problems by appropriately tuning the electronic structure by altering the environment surrounding metal atoms at the active site of single atom catalysts (SACs) [14][15][16][17][18][19][20] .…”

“…12,13 We aim to mitigate these problems by appropriately tuning the electronic structure by altering the environment surrounding metal atoms at the active site of single atom catalysts (SACs). 14–20…”