Ir nanoparticles with ultrahigh dispersion as oxygen evolution reaction (OER) catalysts: synthesis and activity benchmarking

Abstract

In this work, we present a facile and straightforward approach to synthesize, activate and benchmark small, i.e. 1.6 nm in diameter, Ir nanoparticles (NP) as oxygen evolution reaction (OER) catalysts.

Ir/TiONx/C high-performance oxygen evolution reaction nanocomposite electrocatalysts in acidic media: synthesis, characterization and electrochemical benchmarking protocol

“…In contrast to the CO-stripping method for supported Pt catalysts, there is no generally accepted benchmark method to measure ECSA of supported Ir catalysts in the community. Recent studies propose a couple of new methods to measure ECSA for Ir-based catalysts [42][43][44][45]; however, they are not always suitable for different samples (e.g. supported or unsupported Ir).…”

Bifunctional Pt-IrO2 Catalysts for the Oxygen Evolution and Oxygen Reduction Reactions: Alloy Nanoparticles vs. Nanocomposite Catalysts

“…Prior to all electrochemical measurements and accelerated degradation tests (ADTs), the electrolyte was de-aerated by purging with Ar, the supported monometallic Pt NPs were cleaned by potential cycling between 0.05 VRHE and 1.20 VRHE at a scan rate of 500 mV s -1 until a stable cyclic voltammograms (CVs) could be observed, the supported PtxIry alloy NPs and Pt -IrO2 nanocomposites were cleaned by potential cycling between 0.10 VRHE and 0.30 VRHE at a scan rate of 100 mV s -1 for 20 cycles (in order not to oxidize Ir to obtain the exact value of the ECSA originating from Pt as well as Ir; once Ir is oxidized, the CO stripping method for the Ir ECSA determination does not work as Ir oxide does not adsorb CO). 38 After cleaning, for each bimetallic catalyst layer the following automized measurement procedure was applied using a macro-script of the potentiostat software: CO stripping, Ir oxidation, CO stripping, ORR activity determination, OER activity determination, ADT treatment, ORR activity determination, OER activity determination, CO stripping. The activities are determined with respect to the metal mass (mass activity (MA)) as well as with respect to the electrochemically active surface area (specific activity (SA)).…”

UV-induced syntheses of surfactant-free precious metal nanoparticles in alkaline methanol and ethanol

“…[12][13][14] This was for instance demonstrated with Pt NPs for hydrogenation reaction and Ir NPs for the oxygen evolution reaction. 12,15 The synthesis is performed at low temperature (<80 C) and does not require harsh chemicals. Only a mono-alcohol (e.g.…”