Table 1. Cost Effectiveness of the Production of Metal Oxide NPs.
| solvothermal organic | solvothermal aqueous | automated or manual mechanochemical | |
|---|---|---|---|
| direct cost (USD) | 23650 | 24800 | 22800 |
| solvent | ethanol | water | N/A |
| time | 4 h | 4 h | 5 min |
| heating | 80 °C | 80 °C | N/A |
| sintering | 400 °C for 4 h | 400 °C for 4 h | 400 °C for 4 h |
| steps | 5 | 5 | 2 |
| yield percent (%) (CuO, ZnO) | 79.5%, 47.47% | 41.58%, 69.9% | 87.5%, 82.5%a |
a
The yield percent of the mechanochemical method is the average of the yields from the manual and automated methods.