Copper tungstate

Structural formula
General
Surname	Copper tungstate
other names	Copper tungsten oxide; Copper (II) tungstate;
Molecular formula	CuWO 4
Brief description	odorless yellow-brown solid
External identifiers / databases
EC number	237-022-7
ECHA InfoCard	100,033,642
PubChem	22221750
Wikidata	Q18211785
properties
Molar mass	311.38 g mol −1
Physical state	firmly
density	7.5 g cm −3
Melting point	930 ° C
solubility	practically insoluble in water; Dihydrate soluble in acetic acid and nitric acid ; Dihydrate decomposes into mineral acids ;
safety instructions
GHS labeling of hazardous substances Caution
H and P phrases	H: 302-332-315-319-335
	P: 261-280-305 + 351 + 338-304 + 340-405-501
	As far as possible and customary, SI units are used. Unless otherwise noted, the data given apply to standard conditions .

Copper tungstate is an inorganic chemical compound of copper from the group of tungstates .

Occurrence

Copper tungstate occurs naturally in basic form as the mineral cuproscheelite .

Extraction and presentation

Copper tungstate can be obtained by reacting copper nitrate with sodium tungstate in an aqueous solution.

{\ displaystyle \ mathrm {Cu (NO_ {3}) _ {2} + Na_ {2} WO_ {4} \ \ longrightarrow {} \ CuWO_ {4} \ downarrow +2 \ NaNO_ {3}}}

It can also be produced by reacting copper (II) oxide with tungsten (VI) oxide at 600 to 800 ° C.

{\ displaystyle \ mathrm {CuO + WO_ {3} \ {\ xrightarrow {800 \, ^ {\ circ} C}} \ CuWO_ {4}}}

properties

Copper tungstate is an odorless yellow-brown solid that is practically insoluble in water. The dihydrate is greenish and changes its color to brown to gray-yellow when heated above 340 ° C, releasing water of crystallization . The anhydrate has a triclinic crystal structure that resembles a distorted wolframite structure with the space group P 1 (space group no. 2) and a = 0.47026 nm , b = 0.58389 nm, c = 0.48784 nm, α = 91.788 °, β = 92.469 °, γ = 82.805 °, Z = 2. The anhydrate has two high-pressure modifications that occur from around 9 and 18 PGa. The monoclinic dihydrate (wolframite structure) retains its crystal structure up to at least 40 GPa. Template: room group / 2

use

Copper tungstate nanopowder is used for supercapacitors and as anode material in lithium ion accumulators ( lithium chlorate and lithium phosphorus oxynitride ). Thin layers of copper tungstate are used for nitric oxide measurements. It is also used in nuclear reactors and as a catalyst in polyester production. It is also used as a photocatalyst (it is an n- type semiconductor with a band gap of 2.25 eV ).

Individual evidence

↑ ^a ^b ^c ^d ^e ^f ^g Data sheet Copper (II) tungsten oxide, 99.5% (metals basis) from AlfaAesar, accessed on June 17, 2016 ( PDF )(JavaScript required) .
^ William M. Haynes: CRC Handbook of Chemistry and Physics, 94th Edition . CRC Press, 2016, ISBN 978-1-4665-7115-0 ( limited preview in Google Book Search).
↑ ^a ^b ^c ^d Dale L. Perry: Handbook of Inorganic Compounds, Second Edition . CRC Press, 2016, ISBN 978-1-4398-1462-8 ( limited preview in Google Book Search).
↑ ^a ^b ^c Gmelin Institute for Inorganic Chemistry and Grenzg: Copper: Part B - Delivery 3: Compounds of copper-lithium to copper-iron reactions of copper ions . Springer-Verlag, 2013, ISBN 978-3-662-13328-6 ( limited preview in Google book search).
↑ Felix Machatschki: Special mineralogy on a geochemical basis . Springer-Verlag, 2013, ISBN 978-3-7091-8006-8 ( limited preview in Google book search).
↑ F. Kosek, J. Horák, J. Kašpar: Conductivity of copper tungstate . In: Collection of Czechoslovak Chemical Communications . tape 24 , no. 6 , January 1, 1959, ISSN 1212-6950 , p. 2034-2037 , doi : 10.1135 / cccc19592034 .
↑ Kihlborg L., Gebert E .: CuWO ₄ , a distorted Wolframite-type structure . In: Acta Crystallographica Section B: Structural Crystallography and Crystal Chemistry . tape 26 , no. 7 , July 15, 1970, doi : 10.1107 / S0567740870003515 .
↑ formatex.info: Structural refinement and photocatalytic properties of CuWO4 crystals , ELS Souza1, CJ Dalmaschio2, MGR Filho1, GE Luz Jr.1, RS Santos1, E. Longo3 and LS Cavalcante, August 28, 2014, accessed June 17, 2016
↑ Li Wang, Feng Ke, Qinglin Wang, Jiejuan Yan, Cailong Liu, Xizhe Liu, Yanchun Li, Yonghao Han, Yanzhang Ma, Chunxiao Gao: Effect of crystallization water on the structural and electrical properties of CuWO ₄ under high pressure . In: Applied Physics Letters . tape 107 , no. 20 , November 16, 2015, p. 201603 , doi : 10.1063 / 1.4935978 .
↑ Juan Carlos Colmenares, Yi-Jun Xu: Heterogeneous Photocatalysis: From Fundamentals to Green Applications . Springer, 2016, ISBN 978-3-662-48719-8 ( limited preview in Google book search).

[Alfa-1] ↑ ^a ^b ^c ^d ^e ^f ^g Data sheet Copper (II) tungsten oxide, 99.5% (metals basis) from AlfaAesar, accessed on June 17, 2016 ( PDF )(JavaScript required) .

[CRC-2] William M. Haynes: CRC Handbook of Chemistry and Physics, 94th Edition . CRC Press, 2016, ISBN 978-1-4665-7115-0 ( limited preview in Google Book Search).

[Dale_L._Perry-3] Dale L. Perry: Handbook of Inorganic Compounds, Second Edition . CRC Press, 2016, ISBN 978-1-4398-1462-8 ( limited preview in Google Book Search).

[Gmelin-4] Gmelin Institute for Inorganic Chemistry and Grenzg: Copper: Part B - Delivery 3: Compounds of copper-lithium to copper-iron reactions of copper ions . Springer-Verlag, 2013, ISBN 978-3-662-13328-6 ( limited preview in Google book search).

[5] Felix Machatschki: Special mineralogy on a geochemical basis . Springer-Verlag, 2013, ISBN 978-3-7091-8006-8 ( limited preview in Google book search).

[6] F. Kosek, J. Horák, J. Kašpar: Conductivity of copper tungstate . In: Collection of Czechoslovak Chemical Communications . tape 24 , no. 6 , January 1, 1959, ISSN 1212-6950 , p. 2034-2037 , doi : 10.1135 / cccc19592034 .

[7] Kihlborg L., Gebert E .: CuWO ₄ , a distorted Wolframite-type structure . In: Acta Crystallographica Section B: Structural Crystallography and Crystal Chemistry . tape 26 , no. 7 , July 15, 1970, doi : 10.1107 / S0567740870003515 .

[formatex.info-8] rmatex.info: Structural refinement and photocatalytic properties of CuWO4 crystals , ELS Souza1, CJ Dalmaschio2, MGR Filho1, GE Luz Jr.1, RS Santos1, E. Longo3 and LS Cavalcante, August 28, 2014, accessed June 17, 2016

[9] Li Wang, Feng Ke, Qinglin Wang, Jiejuan Yan, Cailong Liu, Xizhe Liu, Yanchun Li, Yonghao Han, Yanzhang Ma, Chunxiao Gao: Effect of crystallization water on the structural and electrical properties of CuWO ₄ under high pressure . In: Applied Physics Letters . tape 107 , no. 20 , November 16, 2015, p. 201603 , doi : 10.1063 / 1.4935978 .

[10] Juan Carlos Colmenares, Yi-Jun Xu: Heterogeneous Photocatalysis: From Fundamentals to Green Applications . Springer, 2016, ISBN 978-3-662-48719-8 ( limited preview in Google book search).