Intelligent process monitoring of smart polymer composites using large area graphene coated fabric sensor.

Herein, we report the development of an online process monitoring system for vacuum-assisted resin transfer molding (VARTM) process using large area graphene coated in-situ fabric sensor. Besides imparting excellent mechanical properties to the final composites, these sensors provide critical information during the composite processing including detecting defects and evaluating processing parameters. The obtained information can be used to create a digital passport of the manufacturing phase to develop a cost-effective production technique and fabricate high-quality composites.  The fabric sensor was produced using a scalable dip-coating process by coating 1-, 3- or 5-layers of thermally reduced graphene oxide (rGO) onto glass fabric surface according to the number of dips of the fabrics into GO solution. The electrical resistances from all electrode pairs were simultaneously and continuously recorded during distinct stages of the VARTM process to determine the relative conductance. During the vacuum cycle, the range of relative conductance increased with the number of coated rGO layers, with the 5-layer rGO-coated sensor showing the highest conductance range of 16.9 %. Additionally, it was observed that the 5-layer coated sensor showed a consistent decrease in conductance during the infusion phase due to the fluid flow pressure dominating the resin electrical conductivity.

Nano-Carbon Electrodes for Thermal Energy Harvesting.

Thermogalvanic cells are capable of converting waste heat (generated as a by-product of almost all human activity) to electricity. These devices may alleviate the problems associated with the use of fossil fuels to meet the world's current demand for energy. This review discusses the developments in thermogalvanic systems attained through the use of nano-carbons as the electrode materials. Advances in cell design and electrode configuration that improve performance of these thermo converters and make them applicable in a variety of environments are also summarized. It is the aim of this review to act as a channel for further developments in thermogalvanic cell design and electrode engineering.

Carbon nanotube - reduced graphene oxide composites for thermal energy harvesting applications.

By controlling the SWNT-rGO electrode composition and thickness to attain the appropriate porosity and tortuosity, the electroactive surface area is maximized while rapid diffusion of the electrolyte through the electrode is maintained. This leads to an increase in exchange current density between the electrode and electrolyte which results in enhanced thermocell performance.