| CuO Thin Films | |||
| Temperature | Optical Bandgap (Tauc) | ||
| Air | O2 | N2 | |
| Room Temperature | 2.19 eV | ||
| 100˚C | 2.12 eV | 2.16 eV | 2.17 eV |
| 200˚C | 2.09 eV | 2.13 eV | 2.10 eV |
| 300˚C | 2.08 eV | 2.11 eV | 2.09 eV |
| 400˚C | 2.05 eV | 2.09 eV | 2.08 eV |