Editing Solid-state chemistry (section)

===High-temperature methods===

==== Ceramic method ====
The ceramic method is one of the most common synthesis techniques.<ref name=":0">{{Cite book |last=Rao |first=C. N. R. |url=https://www.worldcat.org/oclc/908260711 |title=Essentials of inorganic materials synthesis |date=2015 |others=Kanishka Biswas |isbn=978-1-118-89267-1 |location=Hoboken, New Jersey |oclc=908260711}}</ref> The synthesis occurs entirely in the solid state.<ref name=":0" />  The reactants are ground together, formed into a pellet using a pellet press and hydraulic press, and heated at high temperatures.<ref name=":0" /> When the temperature of the reactants are sufficient, the ions at the grain boundaries react to form desired phases. Generally ceramic methods give polycrystalline powders, but not single crystals. 

Using a [[mortar and pestle]], ResonantAcoustic mixer, or [[ball mill]], the reactants are ground together, which decreases size and increases [[surface area]] of the reactants.<ref>{{Cite journal |last=Pagola |first=Silvina |date=January 2023 |title=Outstanding Advantages, Current Drawbacks, and Significant Recent Developments in Mechanochemistry: A Perspective View |journal=Crystals |language=en |volume=13 |issue=1 |pages=124 |doi=10.3390/cryst13010124 |issn=2073-4352 |doi-access=free |bibcode=2023Cryst..13..124P }}</ref> If the mixing is not sufficient, we can use techniques such as [[Coprecipitation|co-precipitation]] and [[Sol–gel process|sol-gel]].<ref name=":0" /> A chemist forms pellets from the ground reactants and places the pellets into containers for heating.<ref name=":0" /> The choice of container depends on the precursors, the reaction temperature and the expected product.<ref name=":0" /> For example, [[Oxide|metal oxides]] are typically synthesized in silica or alumina containers.<ref name=":0" /> A [[tube furnace]] heats the pellet.<ref name=":0" /> Tube furnaces are available up to maximum temperatures of 2800<sup>o</sup>C.<ref>{{Cite web |title=Tube Furnaces |url=https://thermcraftinc.com/wp-content/uploads/2017/09/TubeFurnaces.pdf |access-date=March 30, 2023}}</ref> [[File:Horno_tubular.jpg|thumb|Tube furnace being used during the synthesis of [[aluminium chloride]]]]

====Molten flux synthesis====
{{main|Flux method}}
[[File:Steps involved in molten flux synthesis.jpg|center|thumb|440x440px|Steps involved in molten flux synthesis<ref name=":3" />]]
Molten flux synthesis can be an efficient method for obtaining single crystals. In this method, the starting reagents are combined with flux, an inert material with a melting point lower than that of the starting materials. The flux serves as a solvent. After the reaction, the excess flux can be washed away using an appropriate solvent or it can be heat again to remove the flux by sublimation if it is a volatile compound. 

Crucible materials have a great role to play in molten flux synthesis. The crucible should not react with the flux or the starting reagent. If any of the material is volatile, it is recommended to conduct the reaction in a sealed ampule. If the target phase is sensitive to oxygen, a carbon- coated fused silica tube or a carbon crucible inside a fused silica tube is often used which prevents the direct contact between the tube wall and reagents.

==== Chemical vapour transport ====
[[Chemical transport reaction|Chemical vapour transport]] results in very pure materials. The reaction typically occurs in a sealed ampoule.<ref name=":2">{{Cite journal |last1=Binnewies |first1=Michael |last2=Glaum |first2=Robert |last3=Schmidt |first3=Marcus |last4=Schmidt |first4=Peer |date=February 2013 |title=Chemical Vapor Transport Reactions - A Historical Review |url=https://onlinelibrary.wiley.com/doi/10.1002/zaac.201300048 |journal=Zeitschrift für anorganische und allgemeine Chemie |language=en |volume=639 |issue=2 |pages=219–229 |doi=10.1002/zaac.201300048}}</ref> A transporting agent, added to the sealed ampoule, produces a volatile intermediate species from the solid reactant.<ref name=":2" /> For metal oxides, the transporting agent is usually Cl<sub>2</sub> or HCl.<ref name=":2" /> The ampoule has a temperature gradient, and, as the gaseous reactant travels along the gradient, it eventually deposits as a crystal.<ref name=":2" /> An example of an industrially-used chemical vapor transport reaction is the [[Mond process]]. The Mond process involves heating impure [[nickel]] in a stream of [[carbon monoxide]] to produce pure nickel.<ref name="pubs.rsc.org"/>