Insights into electrochemical dealloying of Cu out of Au-doped Pt-alloy nanoparticles at the sub-nano-scale

Abstract

Abstract

Resolving the nanoparticles' structure-property relationships at the atomic level: a study of Pt-based electrocatalysts

“…to induce crystal order or disorder ( Hodnik et al., 2014 )), the addition of some dopant or decoration (e.g. with Au ( Gatalo et al., 2016 ; 2018 ; Jovanovič et al., 2016 ; Ruiz-Zepeda et al., 2017 ) or Ru ( Jovanovič et al., 2018a )), or oxidation of the metal in its oxide form (e.g. Ru ( Hodnik et al., 2015 ) or Ir ( Jovanovič et al., 2017b )).…”

“…Therefore, if we wish to use Pt-M-containing electrocatalysts in PEMFCs, it is of paramount importance to understand, lower, and eventually eliminate leaching of M. In order to do this, it is crucial for the PEMFC community to first understand the related chemical and electrochemical phenomena on a fundamental level. Many extensive studies have already addressed the structure-property behavior of Pt-based electrocatalysts ( Baldizzone et al., 2015a ; Gatalo et al., 2018 ; Gong et al., 2020 ; Han et al., 2015 ; Li et al., 2014 ; Oezaslan et al., 2012b ; Strasser and Kühl, 2016 ; Strasser et al., 2010 ; Yu et al., 2012 ; Zalitis et al., 2020 ). However, most of these studies are based on the oversimplified, perfectly shaped model systems, which are based on either model single-crystal measurements or a result of purely theoretical calculations, and thus, do not cover the necessary complexity of real nanoparticulate systems behind these relations.…”

Elucidating the structure-dependent selectivity of CuZn towards methane and ethanol in CO2 electroreduction using tailored Cu/ZnO precatalysts

“…However, dedicated studies, which combine identical location or in-situ microscopy studies with sensitive analytical techniques, are needed to further understanding this phenomenon, which has indeed been reported for other bimetallic systems. 27,28 Fig. 2 (a,b) EDXS elemental maps of Cu@ZnO and ZnO@Cu after activation at -1.1 VRHE for 1 hour.…”

Synthesis and Advanced Electrochemical Characterization of Multifunctional Electrocatalytic Composite for Unitized Regenerative Fuel Cell

“…For the case of ORR, the catalysts with PtCu present a superior activity compared to pure Pt or Ir. The effect of alloying Pt to improve the ORR activity is well-known and has been extensively reported in our previous studies. − Analyzing the results of Figure b, one finds that the best performance is achieved by the TiON-RuPtCu-Ir, both for ORR and ORR. Looking separately at OER, one finds that the presence of Ru has a clear beneficial impact on activity.…”

“…Prior to activity measurements, the catalyst was electrochemically activated for 200 cycles between 0.05 and 1.2 V vs RHE at 300 mV s –1 under Ar. During activation, Cu leaches out of the PtCu particles − improving the activity for ORR compared to pure Pt. After activity measurements, the materials were degraded for 10 000 cycles within variable potential windows (0.4 to 1.0 V vs RHE for “ORR degradation”, 1.0 to 1.2 V vs RHE for “OER degradation” and 0.4 to 1.6 V vs RHE for “ORR & OER or ALL degradation”) under Ar at 1 V s –1 .…”