In-Situ Monitoring of Nanoparticle Formation during Iridium-Catalysed Oxygen Evolution by Real-Time Small Angle X-Ray Scattering

Maya Singer Hobbs, Emma V. Sackville, Andrew J. Smith, Karen J. Edler, Ulrich Hintermair

Research output: Contribution to journalArticle

Abstract

Real-time Small Angle X-Ray Scattering (SAXS) has been used to investigate the homogeneity of a series of molecular iridium complexes during water oxidation catalysis in aqueous NaIO4 solution through a continuous flow cell. The results obtained for the unstable [Cp*Ir(OH2)3]2+ precursor forming amorphous IrOx nanoparticles (NPs) in-situ validate and complement previous Dynamic Light Scattering (DLS) studies by providing enhanced sensitivity for small particle sizes and increased temporal resolution under realistic reaction conditions. Correlating particle formation profiles with O2 evolution traces allowed homogeneous catalysis to be clearly distinguished from heterogeneous catalysis. A series of seven pyridine−alkoxide Cp*Ir complexes are shown to be fully homogeneous by SAXS, validating previous studies and confirming their catalysis to be molecular in nature throughout the reaction.

Original languageEnglish
Pages (from-to)5313-5321
Number of pages11
JournalChemCatChem
Volume11
Issue number21
Early online date19 Aug 2019
DOIs
Publication statusPublished - 7 Nov 2019

Keywords

  • homogeneous vs. heterogeneous catalysis
  • iridium
  • nanoparticles
  • SAXS
  • water oxidation

ASJC Scopus subject areas

  • Catalysis
  • Physical and Theoretical Chemistry
  • Organic Chemistry
  • Inorganic Chemistry

Cite this

In-Situ Monitoring of Nanoparticle Formation during Iridium-Catalysed Oxygen Evolution by Real-Time Small Angle X-Ray Scattering. / Singer Hobbs, Maya; Sackville, Emma V.; Smith, Andrew J.; Edler, Karen J.; Hintermair, Ulrich.

In: ChemCatChem, Vol. 11, No. 21, 07.11.2019, p. 5313-5321.

Research output: Contribution to journalArticle

@article{3348ce5c66d346bb9cb55e95cd2d1faa,
title = "In-Situ Monitoring of Nanoparticle Formation during Iridium-Catalysed Oxygen Evolution by Real-Time Small Angle X-Ray Scattering",
abstract = "Real-time Small Angle X-Ray Scattering (SAXS) has been used to investigate the homogeneity of a series of molecular iridium complexes during water oxidation catalysis in aqueous NaIO4 solution through a continuous flow cell. The results obtained for the unstable [Cp*Ir(OH2)3]2+ precursor forming amorphous IrOx nanoparticles (NPs) in-situ validate and complement previous Dynamic Light Scattering (DLS) studies by providing enhanced sensitivity for small particle sizes and increased temporal resolution under realistic reaction conditions. Correlating particle formation profiles with O2 evolution traces allowed homogeneous catalysis to be clearly distinguished from heterogeneous catalysis. A series of seven pyridine−alkoxide Cp*Ir complexes are shown to be fully homogeneous by SAXS, validating previous studies and confirming their catalysis to be molecular in nature throughout the reaction.",
keywords = "homogeneous vs. heterogeneous catalysis, iridium, nanoparticles, SAXS, water oxidation",
author = "{Singer Hobbs}, Maya and Sackville, {Emma V.} and Smith, {Andrew J.} and Edler, {Karen J.} and Ulrich Hintermair",
year = "2019",
month = "11",
day = "7",
doi = "10.1002/cctc.201901268",
language = "English",
volume = "11",
pages = "5313--5321",
journal = "ChemCatChem",
issn = "1867-3880",
publisher = "Wiley-VCH Verlag",
number = "21",

}

TY - JOUR

T1 - In-Situ Monitoring of Nanoparticle Formation during Iridium-Catalysed Oxygen Evolution by Real-Time Small Angle X-Ray Scattering

AU - Singer Hobbs, Maya

AU - Sackville, Emma V.

AU - Smith, Andrew J.

AU - Edler, Karen J.

AU - Hintermair, Ulrich

PY - 2019/11/7

Y1 - 2019/11/7

N2 - Real-time Small Angle X-Ray Scattering (SAXS) has been used to investigate the homogeneity of a series of molecular iridium complexes during water oxidation catalysis in aqueous NaIO4 solution through a continuous flow cell. The results obtained for the unstable [Cp*Ir(OH2)3]2+ precursor forming amorphous IrOx nanoparticles (NPs) in-situ validate and complement previous Dynamic Light Scattering (DLS) studies by providing enhanced sensitivity for small particle sizes and increased temporal resolution under realistic reaction conditions. Correlating particle formation profiles with O2 evolution traces allowed homogeneous catalysis to be clearly distinguished from heterogeneous catalysis. A series of seven pyridine−alkoxide Cp*Ir complexes are shown to be fully homogeneous by SAXS, validating previous studies and confirming their catalysis to be molecular in nature throughout the reaction.

AB - Real-time Small Angle X-Ray Scattering (SAXS) has been used to investigate the homogeneity of a series of molecular iridium complexes during water oxidation catalysis in aqueous NaIO4 solution through a continuous flow cell. The results obtained for the unstable [Cp*Ir(OH2)3]2+ precursor forming amorphous IrOx nanoparticles (NPs) in-situ validate and complement previous Dynamic Light Scattering (DLS) studies by providing enhanced sensitivity for small particle sizes and increased temporal resolution under realistic reaction conditions. Correlating particle formation profiles with O2 evolution traces allowed homogeneous catalysis to be clearly distinguished from heterogeneous catalysis. A series of seven pyridine−alkoxide Cp*Ir complexes are shown to be fully homogeneous by SAXS, validating previous studies and confirming their catalysis to be molecular in nature throughout the reaction.

KW - homogeneous vs. heterogeneous catalysis

KW - iridium

KW - nanoparticles

KW - SAXS

KW - water oxidation

UR - http://www.scopus.com/inward/record.url?scp=85071887575&partnerID=8YFLogxK

U2 - 10.1002/cctc.201901268

DO - 10.1002/cctc.201901268

M3 - Article

VL - 11

SP - 5313

EP - 5321

JO - ChemCatChem

JF - ChemCatChem

SN - 1867-3880

IS - 21

ER -