The increasing awareness of climate change has led to a growing interest in alternative energy sources that can reduce carbon emissions and dependence on fossil fuels. Osmotic energy, available when fluids with different salt concentration mix, is a promising source of renewable, clean, sustainable, and non- intermittent energy. It is also an abundant potential energy source, as such mixing occurs in nature, but also in industrial processes. Most if the existing technologies for osmotic energy harvesting rely on selective membranes, and produce electricity directly via electrochemical conversion (see Reverse Electro Dialysis). But slective membrane technologies have some drawbacks, for instance for applications that require hydraulic energy.
A novel membrane-free approach is developed at the LIPhy for generating hydraulic energy from solutions of different saline concentrations. We propose to develop a volume swich osmosis (VSO) motor incorporating a completely new process based on filling/emptying cycles of hydrophobic, ion-selective nanoporous materials.
The targeted nanoporous material will be Periodic mesoporous Organosilicas (PMOs) which offer various pore geometry, pore size and surface texture. The goal of the internship is to synthetize such materials in collaboration with Xavier Cattoën from the Institute Néel, and to perform a silanization of these nanoporous structure in LIPhy in order to reach superhydrophobicity. Then, the filling/emptying cycles of these nanoporous materials by various saline solutions will be studied, in order to characterize the solvent and ion penetration in the nanopores.