Thermoelectric materials, equipped for changing warmth into power, are promising while changing over lingering heat into electrical vitality, since they enable us to use scarcely usable or nearly lost warm vitality in a proficient way.
Analysts at the Institute of Materials Science of Barcelona (ICMAB-CSIC) have made a new idea of thermoelectric material, distributed in the journal Energy and Environmental Science. It is a gadget made out of cellulose, delivered in situ in the laboratory by bacteria, with little measures of a conductive nanomaterial, carbon nanotubes, utilizing a supportable and naturally inviting technique.
“Instead of making a material for energy, we cultivate it” clarifies Mariano Campoy-Quiles, an analyst of this examination. “Bacteria, dispersed in an aqueous culture medium containing sugar and carbon nanotubes, produce the nanocellulose fibers that end up forming the device, in which the carbon nanotubes are embedded” proceeds with Campoy-Quiles.
“We obtain a mechanically resistant, flexible and deformable material, thanks to the cellulose fibers, and with a high electrical conductivity, thanks to the carbon nanotubes,” explains Anna Laromaine, researcher of this study. “The intention is to approach the concept of circular economy, using sustainable materials that are not toxic for the environment, which are used in small amounts, and which can be recycled and reused,” explains Anna Roig, researcher of this study, “The device is made with sustainable and recyclable materials, and with a high added value,” sheincludes.
Roig claims that, in contrast with other comparative materials, “this one has a higher thermal stability compared to other thermoelectric materials based on synthetic polymers, which allows it to reach temperatures of 250 °C. In addition, the device does not use toxic elements, and the cellulose can easily be recycled, since it can be degraded by an enzymatic process converting it into glucose, while recovering the carbon nanotubes, which are the most expensive element of the device.” Moreover, the thickness, color and transparency of the material can be controlled.
Campoy-Quiles clarifies that carbon nanotubes have been decided for their measurements: “Thanks to their nanoscale diameter and their few microns in length, carbon nanotubes allow, with very little quantity (in some cases up to 1% ), to obtain electrical percolation, i.e. a continuous path where the electrical charges can travel through the material, allowing cellulose to be conductive.” Additionally, the use of such a small amount of nanotubes (up to a maximum of 10%), while maintaining the overall efficiency of a material containing 100 %, makes the process very economic and energy efficient” adds Campoy-Quiles. “On the other hand, the dimensions of carbon nanotubes are similar to those of cellulose nanofibres, which results in a homogeneous dispersion. In addition, the inclusion of these nanomaterials has a positive impact on the mechanical properties of cellulose, making it even more deformable, extensible and resistant, “adds Roig.
These gadgets could be utilized to create power from residual warmth to sustain sensors in the field of the Internet of Things, Agriculture 4.0 or Industry 4.0. “In the near future, they could be used as wearable devices, in medical or sports applications, for example. And if the efficiency of the device was even more optimized, this material could lead to intelligent thermal insulators or to hybrid photovoltaic-thermoelectric power generation systems” explains Campoy-Quiles. In addition “due to the high flexibility of the cellulose and to the scalability of the process, these devices could be used in applications where the residual heat source has unusual forms or extensive areas, as they could be completely covered with this material” indicates Roig.
Since bacterial cellulose can be home made, maybe we are confronting the initial move towards a new vitality paradigm, where clients will most likely make their very own electric generators. We are still far away, however this investigation is a start. We need to begin some place.
This investigation is the result of an interdisciplinary project between different groups of the Institute of Materials Science of Barcelona (ICMAB-CSIC) in the structure of the “Frontier Inderdisciplinary Projects” call, a vital activity of the Severo Ochoa project of brilliance.