New simple La‐Ni complexes as efficient precursors for functional LaNiO 3 ‐based ceramics

• Published in: Applied organometallic chemistry Vol. 36; no. 2
• Main Authors: Gavrikov, Andrey V., Ilyukhin, Andrey B., Belova, Ekaterina V., Yapryntsev, Alexey D., Khrushcheva, Alena V., Loktev, Alexey S.
• Format: Journal Article
• Language: English
• Published: 01-02-2022
• ISSN: 0268-2605; 1099-0739
• DOI: 10.1002/aoc.6519

Perovskite LaNiO
3
is of immense significance in a range of fields such as heterogeneous catalysis. Herein, new convenient approach for preparing LaNiO
3
via
thermolysis of new simple complexes, [Ni (bpy)
3
] [La (NO
3
)
5
(MeCN)] (
1
, bpy is 2,2'‐bipyridine) and [Ni (phen)
3
] [La (NO
3
)
5
(H
2
O)]·2MeCN (
2
, phen is 1,10‐phenanthroline), is reported. These first examples of unambiguously characterized LaNiO
3
precursors are chemically stable and can be synthesized rapidly in good yields. While virtually monophasic LaNiO
3
can be prepared from
2
via
only 3‐h annealing on air at 800°C, there are always minor admixtures in oxide samples prepared from
1
. Peculiarities of intrinsic thermal transformations of
1
and
2
affecting such difference have been revealed. Thus,
1
and
2
are the first series of compositionally related heterometallic La‐Ni complexes studied as precursors for LaNiO
3
‐based ceramics. Comparatively high surface areas of LaNiO
3
‐based ceramics produced from
1
and
2
at 800°C determine its high catalytic activity towards dry reforming of methane (DRM) to syngas. Nearly quantitative CH
4
and CO
2
conversions as well as CO and H
2
yields were achieved in 800–900°C range without preliminary reduction to Ni/La
2
O
3
composites. Thus, LaNiO
3
‐based ceramics prepared from
1
and
2
are good precursors for in situ production of efficient catalysts for DRM.