Low-temperature Synthesis Of Novel Metal Oxides By Topochemical Reactions

Content Provider	Indian Institute of Science (IISc)
Author	Gopalakrishnan, J.
Editor	Rao, C. N. R.
Copyright Year	1986
Abstract	Novel metal oxides were prepd. at low temps. by topochem. reactions. Topochem. dehydration of $Mo1- \times W \times O_3.H_2O$ provides a convenient route for the prepn. of $Mo1-\timesW\timesO3$ in ReO\times3-type structure. Dehydration of $HMoO_2PO_4.H_2O$ to $HMoO_2PO_4$ results in a topotactic transformation of the parent chain structure to a layered structure in the product. Exchange of Li with protons in $LiNbWO_6$ and $LiTaWO_6$ results in a novel structural transformation from the rutile to the $ReO_3$ structure of the product phases, $HNbWO_6$ and $HTaWO_6$. Topotactic redn. of LaNiO3 and LaCoO3 yields new vacancy-ordered perovskite-related phases, $La_2Ni_2O_5$ and $La_2Co_2O_5$ that cannot be prepd. otherwise. H can be inserted topotactically into $LaNiO_3$ and $LaCoO_3$ around ambient temps. in the presence of Pt-catalyst to yield $HxLaNiO_3$ and $HxLaCoO_3$. Insertion of Bi into $WO_3$ yielding intergrowth W bronzes, $BixWO_3$, can also be viewed as a topotactic process.
File Format	PDF
Journal	PeerReviewed
Language	English
Publisher	Indian Natitonal Science Academy
Publisher Date	1986-01-01
Access Restriction	Authorized
Subject Keyword	Solid State & Structural Chemistry Unit
Content Type	Text
Resource Type	Article