Jump to main content
Jump to site search

Issue 24, 2014
Previous Article Next Article

Efficient water oxidation with organometallic iridium complexes as precatalysts

Author affiliations

Abstract

Catalytic water oxidation has been investigated using five iridium complexes as precatalysts and NaIO4 as an oxidant at various pH conditions. An increase in the activity of all complexes was observed with increasing pH. A detailed analysis of spectroscopic data together with O2-evolution experiments using Cp*Ir(6,6′-dihydroxy-2,2′-bipyridine)(OH2)2+ as a precatalyst indicate that the high catalytic activity is closely connected with transient species (A) that exhibits an absorption band at λmax 590 nm. The formation of this active form is strongly dependent on reaction conditions, and the species was distinctly observed using a small excess of periodate. However, another species absorbing at 600 nm (B), which seems to be a less active catalyst, was also observed and was more prominent at high oxidant concentration. Dynamic light scattering analysis and transmission electron microscopy have identified species B as 120 nm nanoparticles. The ultrafiltration method has revealed that species A can be attributed to particles with size in the range of 0.5–2 nm, possibly small IrOx clusters similar to those described previously by Harriman and co-workers (J. Phys. Chem., 1991, 95, 616–621).

Graphical abstract: Efficient water oxidation with organometallic iridium complexes as precatalysts

Back to tab navigation

Supplementary files

Article information


Submitted
03 Dec 2013
Accepted
30 Jan 2014
First published
30 Jan 2014

Phys. Chem. Chem. Phys., 2014,16, 11976-11987
Article type
Paper

Efficient water oxidation with organometallic iridium complexes as precatalysts

A. Lewandowska-Andralojc, D. E. Polyansky, C. Wang, W. Wang, Y. Himeda and E. Fujita, Phys. Chem. Chem. Phys., 2014, 16, 11976
DOI: 10.1039/C3CP55101F

Social activity

Search articles by author

Spotlight

Advertisements