Graphene Conductivity Ratio Calculator
Calculate the conductivity ratio of graphene relative to standard reference materials. Compare both electrical conductivity (S/m) and thermal conductivity (W/mK) across different graphene types - from pristine monolayer to CVD graphene and graphene composites. Select your reference material and adjust for temperature and doping level to see how graphene performs in real-world conditions. Understand the theoretical advantages and practical limitations of this remarkable 2D material.
Operating temperature in Kelvin (300K = room temperature)
Enhancement (%) = (Ratio - 1) × 100%
Electrical (S/m):
Graphene (monolayer): 1.0×10⁸ | Copper: 5.96×10⁷
Ratio: 1.68 (68% better than copper)
Thermal (W/mK):
Graphene (monolayer): 5,000 | Copper: 400
Ratio: 12.5 (12.5× better than copper)
Temperature effect: σ(T) = σ₃₀₀ × (1 - 0.001 × ΔT)
Graphene conductivity: 1.0×10⁸ S/m
Copper conductivity: 5.96×10⁷ S/m
Ratio: 1.0×10⁸ / 5.96×10⁷ = 1.68
Graphene is 68% more conductive than copper
With moderate doping (1.8×): 1.0×10⁸ × 1.8 = 1.8×10⁸ S/m
Ratio becomes: 1.8×10⁸ / 5.96×10⁷ = 3.02
Doped graphene is 3× better than copper
Practical note: CVD graphene on substrate drops to ~3×10⁷ S/m
How is the graphene conductivity ratio calculated?
The conductivity ratio compares graphene's electrical or thermal conductivity to a reference material (typically copper or silver). Electrical Conductivity Ratio = σ_graphene / σ_reference. Graphene's intrinsic electrical conductivity is approximately 1×10⁸ S/m (Siemens per meter), compared to copper at 5.96×10⁷ S/m, giving a ratio of ~1.68. However, this is for pristine monolayer graphene. Practical considerations reduce this: (1) Bilayer graphene: ratio drops to ~1.2, (2) CVD graphene on substrate: ~0.5-0.8 of copper, (3) Graphene oxide: 0.01-0.1 of copper. Thermal conductivity: graphene (~5,000 W/mK) vs copper (~400 W/mK), ratio ~12.5.
What factors affect graphene's electrical conductivity?
Several factors affect graphene conductivity: (1) Number of layers - monolayer has highest conductivity; each additional layer reduces conductivity by 20-30% due to interlayer scattering. (2) Defect density - point defects and grain boundaries scatter charge carriers; CVD graphene has 10-100× lower mobility than exfoliated graphene. (3) Substrate effects - charged impurities in the substrate (SiO₂, SiC) reduce carrier mobility by 2-5×. (4) Doping - chemical doping can tune conductivity from p-type to n-type. (5) Temperature - at room temperature, phonon scattering limits mobility; cryogenic temperatures increase conductivity by 10-100×.
How does graphene thermal conductivity compare to other materials?
Graphene has the highest known thermal conductivity at ~5,000 W/mK for suspended monolayer. Comparison: Diamond: 2,200 W/mK, Silver: 430 W/mK, Copper: 400 W/mK, Aluminum: 237 W/mK, Silicon: 150 W/mK. The thermal conductivity ratio graphene:copper ≈ 12.5:1. However, supported graphene (on SiO₂) drops to ~600 W/mK due to substrate phonon coupling. Practical graphene films (few-layer, CVD) achieve 100-1,000 W/mK depending on flake size and alignment. For thermal management applications, graphene composites with 10-20% graphene loading achieve 5-20 W/mK, a 2-10× improvement over the base polymer.
What are the practical applications of graphene's conductivity?
Graphene's conductivity enables: (1) Transparent conductive electrodes for touchscreens and solar cells - replacing ITO with 90%+ transparency and <100 Ω/sq sheet resistance. (2) Thermal interface materials for electronics cooling - graphene pads achieve 50-150 W/mK vs 3-5 W/mK for silicones. (3) Conductive inks for printed electronics - graphene inks achieve 10⁴-10⁵ S/m. (4) EMI shielding - graphene films provide >30 dB shielding effectiveness. (5) Supercapacitor electrodes - graphene achieves 100-300 F/g specific capacitance. (6) RF transistors - graphene FETs achieve 100 GHz+ cutoff frequencies.
🔗 Related Calculators
📐 Formula
Enhancement (%) = (Ratio - 1) × 100%
Electrical (S/m):
Graphene (monolayer): 1.0×10⁸ | Copper: 5.96×10⁷
Ratio: 1.68 (68% better than copper)
Thermal (W/mK):
Graphene (monolayer): 5,000 | Copper: 400
Ratio: 12.5 (12.5× better than copper)
Temperature effect: σ(T) = σ₃₀₀ × (1 - 0.001 × ΔT)
📝 Example Calculation
Graphene conductivity: 1.0×10⁸ S/m
Copper conductivity: 5.96×10⁷ S/m
Ratio: 1.0×10⁸ / 5.96×10⁷ = 1.68
Graphene is 68% more conductive than copper
With moderate doping (1.8×): 1.0×10⁸ × 1.8 = 1.8×10⁸ S/m
Ratio becomes: 1.8×10⁸ / 5.96×10⁷ = 3.02
Doped graphene is 3× better than copper
Practical note: CVD graphene on substrate drops to ~3×10⁷ S/m