Single‐Entity Electrocatalysis of Individual "Picked‐and‐Dropped" Co3O4 Nanoparticles on the Tip of a Carbon Nanoelectrode. Issue 7 (14th December 2020)

• Record Type: Journal Article
• Authors: Quast, Thomas; Aiyappa, Harshitha Barike; Saddeler, Sascha; Wilde, Patrick; Chen, Yen‐Ting; Schulz, Stephan; Schuhmann, Wolfgang
• Is Part Of: Angewandte Chemie international edition. Volume 60:Issue 7(2021)
• Page Start: 3576
• Page End: 3580
• Publication Date: 2020-12-14
• Subjects: carbon nanoelectrodes -- Co3O4 -- electrocatalysis -- single-entity electrochemistry -- single-particle immobilization; Chemistry -- Periodicals; 540
• DOI: 10.1002/anie.202014384
• Languages: English
• ISSNs: 1433-7851

Abstract

Abstract: Nano‐electrochemical tools to assess individual catalyst entities are critical to comprehend single‐entity measurements. The intrinsic electrocatalytic activity of an individual well‐defined Co3 O4 nanoparticle supported on a carbon‐based nanoelectrode is determined by employing an efficient SEM‐controlled robotic technique for picking and placing a single catalyst particle onto a modified carbon nanoelectrode surface. The stable nanoassembly is microscopically investigated and subsequently electrochemically characterized. The hexagonal‐shaped Co3 O4 nanoparticles demonstrate size‐dependent electrochemical activity and exhibit very high catalytic activity with a current density of up to 11.5 A cm −2 at 1.92 V (vs. RHE), and a turnover frequency of 532±100 s −1 at 1.92 V (vs. RHE) towards catalyzing the oxygen evolution reaction. Abstract : A SEM‐controlled micromanipulator technique is proposed to pick single Co3 O4 nanoparticles and place them on a modified carbon nanoelectrode surface. The obtained nanoassembly allows to extract the intrinsic oxygen evolution activity of the nanoparticle at industrially relevant current density devoid of film and ensemble effects. Post‐electrochemistry TEM analyses offer insight into structural transformations during electrocatalysis.