The role of structure on the thermal properties of graphitic foams

Nanostructuring effect of multi-walled carbon nanotubes on electrochemical properties of carbon foam as constructive electrode for lead acid battery

“…Later on, coal tar and petroleum pitches were used for the development of CFoam (Chen et al 2006). To make highly crystalline CFoam of high electrical and thermal conductivity, generally mesophase pitch is used as the starting material (Klett et al 2000(Klett et al , 2004 and it is prepared by high temperature and pressure foaming process. It is an expensive process, therefore in the present study, using the simple sacrificial template (Chen et al 2007) technique CFoam is developed from the coal tar pitch (CTP) (Yadav et al 2011).…”

Thermal conductivity enhancement of laser induced graphene foam upon P3HT infiltration

“…These constants were derived for CVD grown graphitic foam networks and may not exactly correlate with our material system; however, because our material has a relatively high density and low bulk thermal conductivity, simpler models (Equations (1) and (2) in Ref. 15) with constants that are universally applied to all foam systems produce results within the uncertainty bounds associated with our density measurements. The bulk density (GF density) and the solid density (graphene ligament density) are both denoted by q where the bulk is measured to be 385 6 70 mg/cm 3 and the ligament value is taken from the literature as 2.2 g/cm 3 .…”

“…109, 253107-1 plane thermal conduction as free standing foams or when combined with secondary polymer to form a composite. 13,14 The percolated skeletal carbon ligaments provide heat transport pathways with no interfacial contact points and hence reduced interfacial phonon scattering, and graphene foam composite systems have demonstrated ligament thermal conductivities greater than 1600 W/m-K. 15 In addition, free standing graphene foams, with ligament thermal conductivity estimated to be 500 W/m-K, have demonstrated high effective thermal conductivity under compression and exceptional performance in thermal interface applications. 16 However, expensive, high temperature and time consuming CVD or pyrolytic methods are often used to fabricated graphene foams, pricing graphene foam based TIMs out of the commercial market [13][14][15][16] (high performance TIMs typically sell for between $0.5 and $5.00/in.…”

“…These measured values and the manufacturer specified density of the PI film (1.42 g/cm 3 ) are then used to calculate the LIG density. Using the measured 6% duty cycle LIG density and the measured bulk thermal conductivity as a function of polymer filling (k Bulk ), the estimated ligament thermal conductivity (k Solid ) is calculated and plotted in Figure 2 utilizing a simple analytical model to predict the thermal conductivity of connected graphite networks 15 (Equation (1))…”

“…The bulk density (GF density) and the solid density (graphene ligament density) are both denoted by q where the bulk is measured to be 385 6 70 mg/cm 3 and the ligament value is taken from the literature as 2.2 g/cm 3 . 15 The blue shaded region represents the upper and lower bounds of the estimated ligament conductivity as a function of GF density, where the bounds are determined by the uncertainty in the density measurements. The relatively low values of GF ligament thermal conductivity are likely due to the ultra-polycrystalline nature of the LIG foams and poor structural integrity (fractured ligaments), which will both contribute to enhanced interfacial phonon scattering and contact resistance.…”