posted on 2021-12-03, 13:05authored byKyeounghak Kim, Jinuk Byun, Hyunjoong Kim, Kug-Seung Lee, Hyeon Seok Lee, Jiheon Kim, Taeghwan Hyeon, Jae Jeong Kim, Jeong Woo Han
Nitrous
oxide (N2O) is a notorious greenhouse gas because
of its higher global warming potential and longer lifetime than those
of CO2 and CH4. Here, we present a rational
design of a highly stable and active electrocatalyst that surpasses
the activity of conventional Pd catalysts for N2O 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 N2O. 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.