View source for Lithium titanate

{{Split|date=May 2022|lithium titanate|lithium titanate spinel|lithium metatitanate|discuss=Talk:lithium titanate#Split}}
{{Chembox
| Verifiedfields = changed
| Watchedfields = changed
| verifiedrevid = 431743819
| ImageFile1 = Lithium titanate powder.jpg
| ImageFile2 = File:Li2TiO3.png
| ImageSize =
| ImageCaption2 = <span style="color:#FF9900; background-color:#FF9900;">__</span>[[Lithium|Li]]<sup>+</sup>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;<span style="color:#C0C0C0;background-color:#C0C0C0;">__</span> [[Titanium|Ti]]<sup>4+</sup>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;<span style="color:#FF0000;background-color:#FF0000;">__</span> [[Oxygen|O]]<sup>2−</sup>
| ImageAlt =
| IUPACName =
| OtherNames =Lithium metatitanate
|Section1={{Chembox Identifiers
| CASNo =12031-82-2
| CASNo_Ref = {{cascite|correct|CAS}}
| ChemSpiderID = 141418
| EC_number = 234-759-6
| PubChem = 160968
| InChI = 1S/2Li.3O.Ti/q2*+1;3*-2;+4
| InChIKey = AXQWGBXVDWYWDE-UHFFFAOYSA-N
| SMILES = [Li+].[Li+].[O-2].[O-2].[O-2].[Ti+4]
 }}
|Section2={{Chembox Properties
| Formula = Li<sub>2</sub>TiO<sub>3</sub>
| MolarMass = 109.76
| Appearance = White powder<ref name=crc/> 
| Density = 3.43&nbsp;g/cm<sup>3</sup><ref name="Laan">{{cite journal|doi=10.1016/S0022-3115(98)00794-6|title=Properties of lithium metatitanate pebbles produced by a wet process|journal=Journal of Nuclear Materials|volume=271-272|pages=401–404|year=1999|last1=Van Der Laan|first1=J.G|last2=Muis|first2=R.P|bibcode=1999JNuM..271..401V}}</ref>
| MeltingPtC = 1533
| MeltingPt_ref=<ref name=crc>{{cite journal| title= Solution based synthesis of mixed-phase materials in the Li<sub>2</sub>TiO<sub>3</sub>-Li<sub>4</sub>SiO<sub>4</sub> system | journal= Journal of Nuclear Materials| year=2014| volume=456| pages=151–161
| doi=10.1016/j.jnucmat.2014.09.028 | arxiv=1410.7128| last1= Hanaor| first1= Dorian A.H.| last2= Kolb| first2= Matthias H.H.| last3= Gan| first3= Yixiang| last4= Kamlah| first4= Marc| last5= Knitter| first5= Regina| bibcode= 2015JNuM..456..151H| s2cid= 94426898}}</ref>
| BoilingPt =
| Solubility = }}
| Section3 = {{Chembox Structure
| Structure_ref =<ref>Claverie J., Foussier C., Hagenmuller P. (1966) ''Bull. Soc. Chim. Fr.'' 244-246</ref>
| CrystalStruct = Monoclinic, [[Pearson symbol|mS48]], No. 15
| SpaceGroup = C2/c
| PointGroup = 
| LattConst_a = 0.505 nm
| LattConst_b = 0.876 nm
| LattConst_c = 0.968 nm
| LattConst_alpha = 90°
| LattConst_beta = 100°
| LattConst_gamma = 90°
| LattConst_ref =
| LattConst_Comment = 
| UnitCellVolume = 0.4217 nm<sup>3</sup>
| UnitCellFormulas = 8
  }}
|Section8={{Chembox Hazards
| MainHazards =
| FlashPt =
| AutoignitionPt = }}
}}

'''Lithium titanates''' are [[chemical compound]]s of [[lithium]], [[titanium]] and [[oxygen]]. They are [[mixed oxide]]s and belong to the [[titanate]]s. The most important lithium titanates are:
* [[lithium titanate spinel]], Li<sub>4</sub>Ti<sub>5</sub>O<sub>12</sub> and the related compounds up to Li<sub>7</sub>Ti<sub>5</sub>O<sub>12</sub>. These titanates are used in [[Lithium-titanate battery|lithium-titanate batteries]].
* lithium metatitanate, a compound with the [[chemical formula]] Li<sub>2</sub>TiO<sub>3</sub> and a melting point of {{convert|1533|C|F}}<ref name="Knitter">{{cite journal|url=https://hal.archives-ouvertes.fr/hal-02307643/document|author1=Dorian Hanaor|author2=Matthias Kolb|author3=Yixiang Gan|author4=Marc Kamlah|author5=Regina Knitter|title=Mixed phase materials in the Li<sub>4</sub>SiO<sub>4</sub> Li<sub>2</sub>TiO<sub>3</sub> system|journal=Journal of Nucl Materials|year=2014|volume=456|pages=151–166}}</ref> It is a white powder with possible applications in [[tritium]] breeding materials in nuclear fusion applications.
Other lithium titanates, i.e. mixed oxides of the system Li<sub>2</sub>O–TiO<sub>2</sub>, are:
* Lithium orthotitanate Li<sub>4</sub>TiO<sub>4</sub>, melting point of {{convert|1200|C|F}}<ref name="Knitter" />
* Ramsdellite lithium titanate Li<sub>2</sub>Ti<sub>3</sub>O<sub>7</sub> and Li<sub>''x''</sub>TiO<sub>2</sub> (0 ≦ ''x'' ≦ 0.57)  with ramsdellite structure.<ref>{{Cite journal |last1=Tsuyumoto |first1=Isao |last2=Moriguchi |first2=Takumi |date=October 2015 |title=Synthesis and lithium insertion properties of ramsdellite LixTiO2 anode materials |url=https://linkinghub.elsevier.com/retrieve/pii/S0025540815003840 |journal=Materials Research Bulletin |language=en |volume=70 |pages=748–752 |doi=10.1016/j.materresbull.2015.06.014|url-access=subscription }}</ref>

== Lithium metatitanate ==
'''Lithium metatitanate''' is a compound with the [[chemical formula]] Li<sub>2</sub>TiO<sub>3</sub>. It is a white powder with a melting point of {{convert|1533|C|F}}.<ref name="Knitter"/> It is also used as an additive in [[porcelain]] [[Vitreous enamel|enamel]]s and [[ceramic]] insulating bodies based on titanates. It is frequently utilized as a [[flux (metallurgy)|flux]] due to its good stability.<ref name="Thermograde">{{cite web|url=http://www.thermograde.com/our-products/lithium-titanate/prod_16.html|title=Lithium Titanate Fact Sheet|work=Product Code: LI2TI03|publisher=Thermograde|access-date=24 June 2010|url-status=dead|archive-url=https://web.archive.org/web/20110323125234/http://www.thermograde.com/our-products/lithium-titanate/prod_16.html|archive-date=23 March 2011}}</ref> In recent years, along with other lithium ceramics, metatitanate pebbles have been the subject of research efforts towards [[tritium]] breeding materials in nuclear fusion applications.<ref name="l2s">{{cite journal| last1=Hanaor| first1=D. A. H.| last2=Kolb| first2=M. H. H.| last3=Gan| first3=Y.| last4=Kamlah| first4=M.| last5=Knitter| first5=R.| title= Solution based synthesis of mixed-phase materials in the Li<sub>2</sub>TiO<sub>3</sub>-Li<sub>4</sub>SiO<sub>4</sub> system | journal= Journal of Nuclear Materials | year=2014| volume=456| pages=151–161| doi=10.1016/j.jnucmat.2014.09.028| arxiv=1410.7128| bibcode=2015JNuM..456..151H| s2cid=94426898}}</ref>

==Crystallization==
The most stable lithium titanate phase is β-Li<sub>2</sub>TiO<sub>3</sub> that belongs to the [[monoclinic system]].<ref name=Vijayakumar>{{cite journal |author1=Vijayakumar M. |author2=Kerisit, S. |author3=Yang, Z. |author4=Graff, G. L. |author5=Liu, J. |author6=Sears, J. A. |author7=Burton, S. D. |author8=Rosso, K. M. |author9=Hu, J. |title = Combined 6,7Li NMR and Molecular Dynamics Study of Li Diffusion in Li<sub>2</sub>TiO<sub>3</sub>| journal = Journal of Physical Chemistry | volume = 113 |issue=46 | pages = 20108–20116 | year = 2009 | doi=10.1021/jp9072125}}</ref> A high-temperature cubic phase exhibiting solid-solution type behavior is referred to as γ-Li<sub>2</sub>TiO<sub>3</sub> and is known to form reversibly above temperatures in the range 1150-1250&nbsp;°C.<ref>{{cite journal| last1=Kleykamp| first1=H | title= Phase equilibria in the Li–Ti–O system and physical properties of Li2TiO3 | journal= [[Fusion Engineering and Design]] |year= 2002| volume=61| pages=361–366| doi=10.1016/S0920-3796(02)00120-5 }}</ref> A metastable cubic phase, isostructural with γ-Li<sub>2</sub>TiO<sub>3</sub>  is referred to as α-Li<sub>2</sub>TiO<sub>3</sub>; it is formed at low temperatures, and transforms to the more stable β-phase upon heating to 400&nbsp;°C.<ref>{{cite journal| last1=Laumann| first1=Andreas| last2=Jensen| first2=Ørnsbjerg| last3=Kirsten| first3=Marie| last4=Tyrsted | first4=Christoffer | title= In-situ Synchrotron X-ray Diffraction Study of the Formation of Cubic Li<sub>2</sub>TiO<sub>3</sub> Under Hydrothermal Conditions| journal= Eur. J. Inorg. Chem.|year= 2011| volume=2011| issue=14| pages=2221–2226| doi=10.1002/ejic.201001133}}</ref>

==Uses in sintering==
The [[sintering]] process is taking a powder, putting it into a mold and heating it to below its [[melting point]]. Sintering is based on atomic diffusion, the atoms in the powder particle diffuse into surrounding particles eventually forming a solid or porous material.

It has been discovered that Li<sub>2</sub>TiO<sub>3</sub> powders have a high purity and good sintering ability.<ref name="Sahu">{{cite journal|author1=A. Shrivastava|author2=T. Kumar|author3=R. Shukla|author4=P. Chaudhuri|title=Li<sub>2</sub>TiO<sub>3</sub> pebble fabrication by freeze granulation & freeze drying method|journal=Fusion Eng. Des.|date=July 2021|volume=168|page=112411|doi=10.1016/j.fusengdes.2021.112411 |s2cid=233544019 |url=https://doi.org/10.1016/j.fusengdes.2021.112411|access-date=27 March 2022|url-access=subscription}}</ref>

==Uses as a cathode==

===Molten carbonate fuel cells===
Lithium titanate is used as a cathode in layer one of a double layer cathode for [[molten carbonate fuel cell]]s. These fuel cells have two material layers, layer 1 and layer 2, which allow for the production of high power molten carbonate fuel cells that work more efficiently.<ref name="EPO">Prohaska, Armin et al. (1997) {{US Patent|6420062}} "Double layer cathode for molten carbonate fuel cells and method for producing the same"</ref>

===Lithium-ion batteries===
Li<sub>2</sub>TiO<sub>3</sub> is used in the cathode of some [[lithium-ion batteries]], along with an aqueous binder and a conducting agent. Li<sub>2</sub>TiO<sub>3</sub> is used because it is capable of stabilizing the high capacity cathode conducting agents; LiMO<sub>2</sub> (M=Fe, Mn, Cr, Ni). Li<sub>2</sub>TiO<sub>3</sub> and the conduction agents (LiMO<sub>2</sub>) are layered in order to create the cathode material. These layers allow for the occurrence of lithium diffusion.

==Lithium-titanate battery==
The [[lithium-titanate battery]] is a rechargeable battery that is much faster to charge than other lithium-ion batteries. It differs from other lithium-ion batteries because it uses lithium-titanate on the [[anode]] surface rather than carbon. This is advantageous because it does not create a solid electrolyte interface layer, which acts as a barrier to the ingress and egress of Li-ion to and from the anode. This allows lithium-titanate batteries to be recharged more quickly and provide higher currents when necessary. A disadvantage of the lithium-titanate battery is a much lower capacity and voltage than the conventional lithium-ion battery. The lithium-titanate battery is currently being used in battery electric vehicles{{fact|date=January 2024}} and other specialist applications.

==Tritium breeding==
Fusion reactions, such as those in the proposed [[ITER]] thermonuclear demonstrator reactor, are fueled by [[tritium]] and [[deuterium]]. Tritium resources are extremely limited in their availability, with total resources currently estimated at twenty kilograms. Lithium-containing ceramic pebbles can be used as solid breeder materials in a component known as a helium-cooled [[Breeding blanket|breeder blanket]] for the production of tritium.<ref>{{cite journal|author1=A. Shrivastava|author2=R. Shukla|author3=P. Chaudhuri|title=Effect of porosity on thermal conductivity of Li<sub>2</sub>TiO<sub>3</sub> ceramic compact|journal=Fusion Eng. Des.|volume=166|date=May 2021|page=112318|doi=10.1016/j.fusengdes.2021.112318 |s2cid=234865541 |url=https://doi.org/10.1016/j.fusengdes.2021.112318|url-access=subscription}}</ref> The breeding blanket constitutes a key component of the ITER reactor design. In such reactor designs tritium is produced by neutrons leaving the plasma and interacting with lithium in the blanket. Li<sub>2</sub>TiO<sub>3</sub> along with Li<sub>4</sub>SiO<sub>4</sub> are attractive as tritium breeding materials because they exhibit high tritium release, low activation, and chemical stability.<ref name="l2s" />

===Synthesis of lithium-titanate breeder powder===
Li<sub>2</sub>TiO<sub>3</sub> powder is most commonly prepared by the mixing of [[lithium carbonate]], Ti-nitrate solution, and [[citric acid]] followed by [[calcination]], [[wikt:compaction|compaction]], and [[sintering]]. The nanocrystalline material created is used as a breeder powder due to its high purity and activity.<ref>A. Shrivastava, T. Kumar, R. Shukla, P. Chaudhuri, Li2TiO3 pebble fabrication by freeze granulation & freeze drying method, Fusion Eng. Des. 168 (2021) 112411. https://doi.org/10.1016/j.fusengdes.2021.112411.</ref><ref name="EPO"/><ref name=Aroh>{{cite journal|doi=10.13182/FST13-658|title=Preparation and Characterization of the Lithium Metatitanate Ceramics by Solution-Combustion Method for Indian LLCB TBM|journal=Fusion Science and Technology|volume=65|issue=2|pages=319–324|year=2014|last1=Shrivastava|first1=A.|last2=Makwana|first2=M.|last3=Chaudhuri|first3=P.|last4=Rajendrakumar|first4=E.|bibcode=2014FuST...65..319S |s2cid=123286397 }}</ref>

==See also==
* [[Lithium battery]]

==References==
{{Reflist|30em}}
{{Commons category|Lithium titanate}}
{{Lithium compounds}}
{{Titanium compounds}}
{{Titanates}}

[[Category:Titanates]]
[[Category:Lithium salts]]