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Abstract Searching for a connection between the two‐electron redox behavior of Group‐14 elements and their possible use as platforms for the photoreductive elimination of chlorine, we have studied the photochemistry of [(o‐(Ph2P)C6H4)2GeIVCl2]PtIICl2and [(o‐(Ph2P)C6H4)2ClGeIII]PtIIICl3, two newly isolated isomeric complexes. These studies show that, in the presence of a chlorine trap, both isomers convert cleanly into the platinum germyl complex [(o‐(Ph2P)C6H4)2ClGeIII]PtICl with quantum yields of 1.7 % and 3.2 % for the GeIV–PtIIand GeIII–PtIIIisomers, respectively. Conversion of the GeIV–PtIIisomer into the platinum germyl complex is a rare example of a light‐induced transition‐metal/main‐group‐element bond‐forming process. Finally, transient‐absorption‐spectroscopy studies carried out on the GeIII–PtIIIisomer point to a ligand arene–Cl.charge‐transfer complex as an intermediate.
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Anodically Grown Pt(II) Oxide Microelectrode/Nanoelectrode pH Sensor
Operandomeasurements of local pH at the nanoscale can significantly improve the understanding of the complex microenvironments that exist in electrochemical systems. However, attempts to easily fabricate a nano-sized pH electrode that can operate under a wide range of pH conditions and have fast temporal responses have been difficult. Here, we show that an anodic-grown Pt/Pt(II) oxide pH sensor manufactured in alkaline conditions (1 M NaOH) shows a near-Nernstian response (−60 mV/pH) from pH 0 to pH 14, is insensitive to dissolved oxygen, cation, and anion identities, and responds correctly in solution with different ionic strengths. This is in contrast to Pt/Pt(II) oxide films grown in acidic media, which do not demonstrate a Nernstian relationship due to cation interference other than H+. We observed a response time of 2.25 s, corresponding to 90% of the final measured pH, for an approximately twelve-fold pH step change when growing the Pt(II) oxide layer on a platinum nanoelectrode. Our findings emphasize the influence of solution pH used for anodization synthesis on the anodic Pt(II) oxide pH sensing properties. The direct oxidation approach for fabricating Pt/Pt(II) oxide microelectrode/nanoelectrode pH sensors can simplify the manufacture of real-time pH sensors for complex aqueous environments.
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- Award ID(s):
- 1922649
- PAR ID:
- 10554995
- Publisher / Repository:
- The Electrochemical Society
- Date Published:
- Journal Name:
- Journal of The Electrochemical Society
- Volume:
- 171
- Issue:
- 11
- ISSN:
- 0013-4651
- Format(s):
- Medium: X Size: Article No. 117512
- Size(s):
- Article No. 117512
- Sponsoring Org:
- National Science Foundation
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