Systematic Approach to Designing a Highly Efficient Core–Shell Electrocatalyst for N₂O Reduction

Abstract

Nitrous oxide (N 2 O) is a notorious greenhouse gas because of its higher global warming potential and longer lifetime than those of CO 2 and CH 4 . Here, we present a rational design of a highly stable and active electrocatalyst that surpasses the activity of conventional Pd catalysts for N 2 O reduction. Theoretical calculations predicted that the catalytic activity of surface Pd atoms in an Au@Pd core−shell structure can be increased by optimizing the thickness of the Pd shell. This prediction was confirmed by the catalytic activity of an Au substrate on which Pd overlayers of different thicknesses were precisely deposited using the atomic layer deposition method. By applying these findings, we synthesized Au@Pd nanoparticles with an optimal shell thickness that exhibited excellent catalytic activity for electrochemical reduction of N 2 O. The catalytic activity of Au@Pd with a Tafel slope of 0.105 V/dec was much higher than that of Pd/C (0.126 V/dec). Moreover, even after 1000 cycles, the activity decreased by only 16%, whereas it decreased by 44% on the Pd/C catalyst.

Large Au@Pd/PdOx core–porous shell nanoparticles as efficient ethanol oxidation electrocatalysts

“…Based on the results of the XRD and XPS analysis for our Au@Pd core-porous shell NPs, the strain in the Pd shells could be ignored due to the non-conformal growth and also the electron transfer between the Au cores and the thick Pd shells is negligible. [44][45][46] Therefore, the contributions of lattice strain and electron transfer to electrocatalytic activity could be excluded. The high electrocatalytic activity and durability should be mainly ascribed to the porous structure of the Pd shells, which offer more active sites and allow the reactants to enter and contact the inner Pd shell.…”

Development of a high surface area Cu electrocatalyst for effective nitrous oxide reduction reaction

“…The kinetics of the process was also investigated using electrochemical impedance spectroscopy (EIS) to shed light on the origin of enhanced activity. The optimized high surface area electrode exhibited an improved onset potential, surpassing other Cu-based N 2 ORR catalysts previously reported, 21,22,24–26 an increased partial current density towards N 2 , and excellent stability. The performance exhibited by this high surface area Cu electrode affirms its potential as a N 2 ORR catalyst alternative to noble metals.…”

“…20 Various Pd-based catalysts have been investigated for N 2 ORR such as bimetallic catalysts 15 and core-shell structures. 21 While these Pd-based catalysts have the earliest onset potential of any catalyst now available, 15,21,22 their exorbitant cost makes large-scale production of this technology challenging.…”

Efficient urea formation from N2O + CO on dual-atom catalysts TM2/g-CN

“…36,37 Because of its higher global warming potential and longer lifetime than those of CO 2 and methane, removing N 2 O from the atmosphere is also an urgent issue. Current research focuses on N 2 O inversion to harmless N 2 ; 38 the high-value-added products are however never be studied.…”