WO3

semiconductor
· WO3

Tungsten trioxide (WO3) is a transition metal oxide semiconductor with a monoclinic crystal structure, commonly used in optoelectronic and electrochromic devices. It is widely employed in smart windows, gas sensors (particularly for NOx and volatile organic compounds), and photocatalytic applications for environmental remediation and water splitting. Engineers select WO3 for its tunable bandgap, strong absorption in the visible-near-infrared spectrum, and ability to reversibly change color and conductivity under applied voltage or light exposure—making it valuable for applications requiring dynamic optical or electrical response with relatively low processing temperatures.

electrochromic smart windowsgas sensorsphotocatalytic water treatmentphotoelectrochemical hydrogen generationoptical coatings and filterssolid-state battery materials

Compliance & Regulations

?EAR?Conflict Free?RoHS?REACH?TSCA?Prop 65
PropertyValueUnitConditionsSource
Bulk Modulus(K)3 entries
223.4
GPa
169.8
GPa
180.6
GPa
Elastic Compliance Tensor(Sij)
Matrix (redacted)
1/GPa
Elastic Anisotropy(AU)
2.848
-
Elastic Stiffness Tensor(Cij)
Matrix (redacted)
Pa
Poisson's Ratio(ν)2 entries
0.2647
-
0.2700
-
Shear Modulus(G)3 entries
124.7
GPa
110.2
GPa
109.5
GPa
N entriesMultiple entries per property — large groups are collapsed; click a summary row to expand. Use filters above to narrow by form / heat treatment / basis.
Verified Unverified Low confidence (<80%) Link to source
PropertyValueUnitConditionsSource
Density(ρ)
6.741
kg/m³
Verified Unverified Low confidence (<80%) Link to source
PropertyValueUnitConditionsSource
Band Gap(Eg)2 entries
2.900
eV
0.1770
eV
Dielectric Constant (Relative Permittivity)(εr)
14.57
-
Electrical Conductivity(σ)
0.00123
S/cm127°C
Electrical Resistivity(ρe)
8.098
Ω·m127°C
Magnetic Moment(μB)
0.1190
µB
Piezoelectric Modulus(eij)
0.000
C/m²
Thermoelectric Power Factor(PF)
1.429e-9
W/(m·K²)127°C
Seebeck Coefficient(S)2 entries
107.6
μV/K127°C
313.9
µV/K
N entriesMultiple entries per property — large groups are collapsed; click a summary row to expand. Use filters above to narrow by form / heat treatment / basis.
Verified Unverified Low confidence (<80%) Link to source
PropertyValueUnitConditionsSource
Energy Above Hull(ΔEhull)
0.09930
eV/atom
Formation Energy(ΔHf)2 entries
-2.183
eV/atom
-2.281
eV/atom
N entriesMultiple entries per property — large groups are collapsed; click a summary row to expand. Use filters above to narrow by form / heat treatment / basis.
Verified Unverified Low confidence (<80%) Link to source

Regulatory Screening

Environmental

Export Control

RoHS, REACH, and Prop 65 statuses are validated against official substance lists (ECHA SVHC Candidate List, OEHHA Prop 65, RoHS Annex II). Other regulations are estimated from composition and material classification. All screening is a starting point for due diligence — always verify with your supplier before making compliance decisions.