Caesium carbonate
Chemical compound
From Wikipedia, the free encyclopedia
Caesium carbonate or cesium carbonate is a chemical compound with the chemical formula Cs2CO3. It is white crystalline solid. Caesium carbonate has a high solubility in polar solvents such as water, ethanol and DMF. Its solubility is higher in organic solvents compared to other carbonates like potassium carbonate and sodium carbonate, although it remains quite insoluble in other organic solvents such as toluene, p-xylene, and chlorobenzene. This compound is used in organic synthesis as a base.[3] It also appears to have applications in energy conversion.
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 Caesium, Cs Carbon, C Oxygen, O | |
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| Names | |
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| Preferred IUPAC name
Dicaesium carbonate | |
Other names
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| Identifiers | |
3D model (JSmol) |
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| ChemSpider | |
| ECHA InfoCard | 100.007.812 |
| EC Number |
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PubChem CID |
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| UNII | |
CompTox Dashboard (EPA) |
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| Properties | |
| Cs2CO3 | |
| Molar mass | 325.819 g·mol−1 |
| Appearance | white powder |
| Density | 4.072 g/cm3 |
| Melting point | 610 °C (1,130 °F; 883 K) (decomposes) |
| 2605 g/L (15 °C) | |
| Solubility in ethanol | 110 g/L |
| Solubility in dimethylformamide | 119.6 g/L |
| Solubility in dimethyl sulfoxide | 361.7 g/L |
| Solubility in sulfolane | 394.2 g/L |
| Solubility in methylpyrrolidone | 723.3 g/L |
| −103.6·10−6 cm3/mol | |
| Hazards | |
| GHS labelling:[2] | |
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| Danger | |
| H315, H318, H319, H335, H361f, H373 | |
| P203, P260, P264, P264+P265, P271, P280, P302+P352, P304+P340, P305+P351+P338, P305+P354+P338, P317, P318, P319, P321, P332+P317, P337+P317, P362+P364, P403+P233, P405, P501 | |
| Flash point | Non-flammable |
| Related compounds | |
Other anions |
Caesium bicarbonate |
Other cations |
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Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa).
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Preparation
Caesium carbonate can be prepared by thermal decomposition of caesium oxalate.[4] Upon heating, caesium oxalate is converted to caesium carbonate with emission of carbon monoxide.
- Cs2C2O4 → Cs2CO3 + CO
It can also be synthesized by reacting caesium hydroxide with carbon dioxide.[4]
- 2 CsOH + CO2 → Cs2CO3 + H2O
Reactions
Caesium carbonate facilitates the N-alkylation of compounds such as sulfonamides, amines, β-lactams, indoles, heterocyclic compounds, N-substituted aromatic imides, phthalimides, and other similar compounds.[5]
Caesium carbonate and copper(II) chloride are used in the aerobic oxidation of primary alcohols.[6]
Caesium carbonate can also be used in Suzuki, Heck, and Sonogashira coupling reactions.[citation needed]
Caesium carbonate produces carbonylation of alcohols and carbamination[clarification needed] of amines more efficiently than some of the mechanisms that have been introduced in the past.[7]
Caesium carbonate can be used for sensitive synthesis when a balanced strong base is needed.[citation needed]
Use
Solar cells
Relatively effective polymer solar cells are built by thermal annealing of caesium carbonate. Caesium carbonate increases the energy effectiveness of the power conversion of solar cells and enhances the life times of the equipment.[8] Studies done on UPS and XPS reveal that the system will do less work due to the thermal annealing of the Cs2CO3 layer.
Caesium carbonate breaks down into Cs2O and Cs2O2 by thermal evaporation. It was suggested that, when Cs2O combines with Cs2O2 they produce n-type dopes that supply additional conducting electrons to the host devices. This produces a highly efficient inverted cell that can be used to further improve the efficiency of polymer solar cells or to design adequate multijunction photovoltaic cells.[9]
The n-type semiconductor produced by thermal evaporation of Cs2CO3 reacts intensively with metals like Al, and Ca in the cathode. This reaction will reduce the work on the cathode metals.[10]
Organic electronic materials
Nanostructure layers of Cs2CO3 can be used as cathodes for organic electronic materials due to their capacity to increase the kinetic energy of the electrons. Applications include photovoltaic studies, current-voltage measurements, UV photoelectron spectroscopy, X-ray photoelectron spectroscopy, and impedance spectroscopy.
Devices with Cs2CO3 layers have produced equivalent power conversion efficiency compared to devices that use lithium fluoride.[11]
OLEDs
Placing a Cs2CO3 layer in between the cathode and the light-emitting polymer improves the efficiency of the white OLED.[citation needed]