Molecular modeling study on the water-electrode surface interaction in hydrovoltaic energy

Abstract

The global energy problem caused by the decrease in fossil fuel sources, which have negative effects on human health and the environment, has made it necessary to research alternative energy sources. Renewable energy sources are more advantageous than fossil fuels because they are unlimited in quantity, do not cause great harm to the environment, are safe, and create economic value by reducing foreign dependency because they are obtained from natural resources. With nanotechnology, which enables the development of different technologies to meet energy needs, low-cost and environmentally friendly systems with high energy conversion efficiency are developed. Renewable energy production studies have focused on the development of hydrovoltaic technologies, in which electrical energy is produced by making use of the evaporation of natural water, which is the most abundant in the world. By using nanomaterials such as graphene, carbon nanoparticles, carbon nanotubes, and conductive polymers, hydrovoltaic technology provides systems with high energy conversion performance and low cost, which can directly convert the thermal energy resulting from the evaporation of water into electrical energy. The effect of the presence of water on the generation of energy via the interactions between the ion(s) and the liquid–solid surface can be enlightened by the mechanism of the hydovoltaic effect. Here, we simply try to get some tricky information underlying the hydrovoltaic effect by using DFT/B3LYP/6-311G(d, p) computations. Namely, the physicochemical and electronic properties of the graphene surface with a water molecule were investigated, and how/how much these quantities (or parameters) changed in case of the water molecule contained an equal number of charges were analyzed. In these computations, an excess of both positive charge and negative charge, and also a neutral environment was considered by using the Na+, Cl−, and NaCl salt, respectively.

Carbon Cloth Functionalized with Carbon Nanotubes for Hydroelectric Power Generation

“…In the simulation experiment, another charging simulation was plotted. Figure S11­(a), amorphous carbon and carbon cloth with added carbon CNTs were subjected to work function calculations, respectively. , It can be seen that the addition of CNTs to carbon cloth reduces the energy required for the escape of electrons, with the value decreasing from 4.033 to 3.391, which proves that the new material is more favorable for the electrical energy output of the device. Figure S11­(b) shows the fractional coordinate plot of the material, and it is seen that there are inflection points at the ends of the image of the material with the addition of CNTs, proving that heterojunctions have appeared here, which reduces the energy required for the escape of electrons from the surface of the material.…”