IrO2 (iridium oxide) synthesis [closed]








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How do I synthesize $\ce{IrO2}$ from $\ce{IrCl3}$ ? Please suggest a least expensive method.




One elder reference is Brauer's *Handbook of Preparative Inorganic Chemistry*, which states for this compound



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> "In the method of Wöhler and Streicher, $\ce{IrO2}$ is prepared from green $\ce{IrCl3}$ which can readily oxidized in a stream of $\ce{O2}$ at 600$^\circ$C giving blue-black $\ce{IrO2}$.
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> The oxidation of fine iridium powder in a stream of air or oxygen does not give $\ce{IrO2}$ quantitatively. [...]"
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which is accessible in archive.org's public scanned version [here](https://archive.org/details/Handbook_of_Preparative_Inorganic_Chemistry_1_2_Brauer/page/n1635), p. 1590 (book's counting) / p. 1636 (the website's counting) of the 1963-edition by Academic Press. The age of the edition should neither defer you from using it as *a* reference, nor inhibit you to look up additional references.


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Iridium(IV) oxide can be prepared by slow hydrolysis of iridium(III) chloride at ambient conditions. A non-stoichiometric compound is obtained at first which is purified further.



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> Pure iridium oxide has been synthesized through a chimie douce
> process. This synthesis proceeds by a slow basic hydrolysis of
> hydrated iridium(III) chloride, at room temperature. A highly
> disordered oxihydroxide $\ce{IrO\_{1.45}(OH)\_{1.10}·\frac{3}2H2O}$ is first
> obtained.[...]
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Another method is by adding freshly aqueous sodium borohydride to a solution of 0.1 M iridium chloride(molar ratio between them 1:4) at 80°C. The stirring was carried for 10 min till a black colored solid material floated on the surface. The colloidal solution was cooled to room temperature, the solid taken out and washed with ethanol.


**References**


1. N. Bestaoui and E. Prouzet, "A Chimie Douce Route to Pure Iridium Oxide" Chem. Mater.1997, 9, 4, 1036-1041, April 16, **1997** DOI:[https://doi.org/10.1021/cm9606282](https://pubs.acs.org/doi/pdf/10.1021/cm9606282)
2. Chakrapani, K., & Sampath, S. (**2015**). The dual role of borohydride depending on reaction temperature: synthesis of iridium and iridium oxide. Chemical communications, 51 47, 9690-3 ([link](https://www.semanticscholar.org/paper/The-dual-role-of-borohydride-depending-on-reaction-Chakrapani-Sampath/b4c11d9464a8ea75dd2aeba097971d6e14f4d765?p2df))


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