Joule Heating Characteristics of Emulsion‐Templated Graphene Aerogels

Abstract

The Joule heating properties of an ultralight nanocarbon aerogel are investigated with a view to potential applications as energy-efficient, local gas heater and other systems. Thermallyreduced graphene oxide (rGO) aerogels (10 mg cm -3 ) with defined shape are produced via emulsion-templating. Relevant material properties, including thermal conductivity, electrical conductivity and porosity, are assessed. Repeatable Joule heating up to 200°C at comparatively low voltages (~ 1V) and electrical power inputs (~2.5 W cm -3 ) is demonstrated.The steady-state core and surface temperatures are measured, analyzed and compared to analogous two-dimensional nanocarbon film heaters. The assessment of temperature uniformity suggests that heat losses are dominated by conductive and convective heat dissipation at the temperature range studied. The radial temperature gradient of an uninsulated, Joule-heated sample is analyzed to estimate the aerogel's thermal conductivity (around 0.4 W m -1 K -1 ). Fast initial Joule heating kinetics and cooling rates (up to 10 K s -1 )were exploited for rapid and repeatable temperature cycling, important for potential 2 applications in catalysis and for the thermal regeneration of solid adsorbers. These principles may be relevant to wide range of nanocarbon networks and applications.

Recent Progress in Multifunctional Graphene Aerogels

“…As a result, these GAs exhibited excellent elasticity, low density, and good electrical conductivity. Menzel et al (2015) ). Because the power generation per unit volume is constant, the adjustable uniform temperature in GAs offered convenient, low voltage heating in a scalable way.…”

Zeolite Nanocrystals Embedded in Microcellular Carbon Foam as a High‐Performance CO2 Capture Adsorbent with Energy‐Saving Regeneration Properties

“…To increase the efficiency of CO 2 capture even further, zeolites have been incorporated into electrically conductive carbon monoliths to alleviate the amount of energy consumed for the regeneration, as the heat required for zeolite/electrically conductive carbon adsorbent regeneration is produced simply by passing an electric current (Joule heating) through the conductive carbon framework . Thus, such adsorbents have potential for efficient, energy‐saving, and fast desorption of the adsorbed CO 2 through the so‐called electrical swing adsorption process (ESA).…”

M13 Virus Aerogels as a Scaffold for Functional Inorganic Materials

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