We produce graphene dry powders in three categories (see table 1). Drying of graphene powders from aqua or other solutions is carried out by vacuum drying methods with special control of heating and cooling.

Table 1
Parameters | Graphene powder №1 IG-GNP-1 | Graphene powder №2 IG-GNP-2 | Graphene powder №3 IG-GNP-3 | Comments |
Graphene purity | > 99% | > 96% | > 93% | Batch control |
Defects density | Very low | Low | Low | Primary control |
Number of layers | 3 – 7 | 4 – 7 | 4 – 9 | Batch control |
Content of Sp2 | > 91% | > 90% | > 90% | Batch control |
Thickness of graphene flakes (plates) | 1,5-3 nm | 2-4 nm | 3-5 nm | |
Lateral size | to 50 μm | to 30 μm | to 20 μm | |
Electrical conductivity | 5·105 Ohm/m | (7-9)·104 Ohm/m | (2-3)·104 Ohm/m | |
Thermal conductivity | 2200-3400 W/m·К | 1700-2400 W/m·К | 1300-2100 W/m·К | |
Optical transparency, % | 91 | 86 | 81 | |
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 | > 91% | > 91% | > 91% | Primary control |
Color | Practically black | Practically black | Practically black |