In order to improve the performance of thermoelectric materials, nanoinclusions are often used to enhance phonon scattering. In this study, activated carbon, which is porous and thus has a large surface area, was incorporated in GeTe-based materials to cause increased boundary phonon scattering. Carbon dispersed in grain boundaries resulted in improved thermal properties without significant deterioration in electrical properties. Due to the extrinsic addition of activated carbon, the lattice thermal conductivity decreased by 13.8% on average. A maximum dimensionless figure of merit of 1.66 was achieved at 723 K for the Ge0.9Sb0.1Te composition with additional activated carbon.

Carbon electrodes for aqueous supercapacitors should have extensive surface area for higher energy and surface morphology enabling electrolyte ions to access the entire surface. The multiple micropores below 2 nm enhance the

Porous carbon has found commercial applications as a filter material based on the sorption ability of its pores. The pore size and surface properties of the carbon can be varied depending on the type of particles to be filtered. Here, mesoporous carbon was induced through the pyrolysis of polyvinylidene fluoride (PVDF) to fabricate a porous material for microparticle filtration. Because removal of the constituent fluorine at elevated temperature leaves small-sized micropores, the PVDF precursor mainly generates micropores during pyrolysis. To suppress the micropore evolution mechanism, the PVDF precursor was defluorinated before the heat treatment using 1,8-Diazabicyclo[5.4.0]undec-7-ene(DBU) and then pyrolyzed. The suppressed evolution of the micropores during carbon synthesis leads to a lower specific surface area, suggesting low adsorption capacity. The polytetrafluoroethylene (PTFE) was mixed with the PVDF precursor to induce mesoporosity. The PVDF precursor mixed with the PTFE enhanced the surface area since the PTFE could be removed, leaving mesopores after pyrolysis. The effect of the defluorination process on the porosity was investigated by varying the ratio of DBU to vinylidene fluoride unit (1, 5, 10, 20) in the precursor solution. With higher DBU content in the precursor, the micropore evolution was reduced with a lower specific surface area. The porous carbons synthesized from the precursor with a high DBU amount (DBU/vinylidene fluoride unit = 5, 10, 20) were almost entirely composed of mesopores. In addition, the higher DBU content reduced the hydrophilicity of the synthesized carbon. In summary, to separate and absorb relatively large impurities, the mesoporous carbon should be synthesized using a mixture of PVDF and PTFE precursor with an appropriate amount of DBU for a higher specific surface area.