We produce graphene nanoplates and nanoflakes from oxidized graphene in two categories (see table 3). Drying of graphene oxide powders from aqueous or other solutions is carried out by vacuum sublimation drying methods with special control of heating and cooling.
Table 3
| Parameters | Graphene flakes №1 IG-GONF-1 | Graphene flakes №2 IG-GONF-2 | Graphene flakes №3 IG-GONF-3 | Comments |
| Graphene purity | > 99,4% | > 98% | > 97% | Batch control |
| Defects density | Low | Low | Low | Primary control |
| Number of layers | 3 – 7 | 3 – 9 | 4 – 9 | Batch control |
| Content of Sp2 | > 91% | > 90% | > 90% | Batch control |
| Thickness of graphene flakes (plates) | 1,5-3 nm | 2-3 nm | 3-4 nm | |
| Lateral size | to 100 μm | to 50 μm | to 30 μm | |
| Electrical conductivity | (6-8)·105 Ohm/m | (2-5)·105 Ohm/m | (8-9)·104 Ohm/m | |
| Thermal conductivity | 2500-3400 W/m·К | 1800-2900 W/m·К | 1400-2600 W/m·К | |
| Optical transparency, % | 95 | 94 | 93 | |
| True density | 1,9–2,2 g/cm3 | 1,9–2,2 g/cm3 | 1,9–2,2 g/cm3 | Bulk density |
| Content of hybridized carbon | > 95% | > 94% | > 93% | Primary control |
| Colour | Practically black | Practically black | Practically black |