Blue energy harvesting from nanostructured carbon materials

Nowadays, energy issue and environmental problem are two of the most crucial points to deal with. In 2018, less than the 15% of the sources of the total energy supply were renewable. Being so addicted to coal, oil and natural gas brought to an emission of 33.513 Mt of CO2 in that year[1]. For these reasons, a drastic change and a new strategy are needed forcing us to harvest energy from renewable sources. Due to the fact that the 71% of the Earth is water-covered, recovering the potential energy stored in the water is a suggested way forward. In the last years, there has been a growing interest in the so-called "Blue Energy", which is linked to all natural phenomena related to water that cause movement of energy. Basically, it is possible to distinguish three different types of water motion resulting useful for our purpose: the movement of the droplets, the water flow and the phase change. The last will be the one considered within this thesis. Furthermore, thanks to the evolution of technology, it has been observed that carbon-based nanomaterials can play a fundamental role in this specific area because of their multiple properties. They are usually cheap, have a good electrical conductivity and you may find them in different forms (as powders, fibers, etc). The goal set is to create a device capable to harvest energy by focusing on the effect of the water evaporation from different nanostructured carbon materials. In fact, it is possible to obtain a constant voltage generation (without any other external source of power) taking advantage of the interaction of water molecules and carbon layers, as previously shown by some studies. Since none of these were focused on the use graphene oxide (GO), it was chosen as the main material of the research. Another reason for which GO is a good choice for my application is that it presents several good properties: high mechanical strength, electrical conductivity and the hydrophilicity.