Triboelectric Characterization of Colloidal TiO2 for Energy Harvesting Applications

Abstract

Nowadays, energy-related issues are of paramount importance. Every energy transformation process results in the production of waste heat that can be harvested and reused, representing an ecological and economic opportunity. Waste heat to power (WHP) is the process of converting the waste heat into electricity. A novel approach is proposed based on the employment of liquid nano colloids. In this work, the triboelectric characterization of TiO2 nanoparticles dispersed in pure water and flowing in a fluorinated ethylene propylene (FEP) pipe was conducted. The idea is to exploit the waste heat to generate the motion of colloidal TiO2 through a FEP pipe. By placing an Al ring electrode in contact with the pipe, it was possible to accumulate electrostatic charges due to the triboelectric effect between the fluid and the inner pipe walls. A peristaltic pump was used to drive and control the flow in order to evaluate the performances in a broad fluid dynamic spectrum. The system generated as output relatively high voltages and low currents, resulting in extracted power ranging between 0.4 and 0.6 nW. By comparing the power of pressure loss due to friction with the extracted power, the electro-kinetic efficiency was estimated to be 20%.

Liquid-state pyroelectric energy harvesting

“…Thus, the idea to combine solid and liquid properties to achieve better results in harvesting efficiency for applications where flexibility is fundamental, exploiting the properties of nanomaterials, comes straightforward. The use of colloids, defined as solid nanoparticles dispersed in a carrier fluid, is our natural framework, in a study that starts from a toroidal dynamo (TORODYNA) exploiting thermomagnetic advection, 15 encompasses triboelectric colloids, 16 and finally aims at creating colloidal energy systems. 17 Here, an experimental apparatus for monitoring the shortcircuit current and open-circuit voltage production brought by the PyE colloid under different heating conditions is presented.…”

“…The functional colloid is heated up in a reservoir by means of a heating plate and then forced using a peristaltic pump into a Fluorinated Ethylene Propylene (FEP) pipe. 16 Along the loop the fluid is subject to forced convection cooling. In order to collect the electrostatic charges developed thanks to the PyE and carried by the BT NPs, two titanium electrodes are placed along the pipe going in direct contact with the colloid.…”

Waste Heat to Power: Technologies, Current Applications, and Future Potential

“…The idea is to combine solid and liquid properties, realizing a stable suspension of nanoparticles in a carrier fluid, and move this mixture by means of the combination of thermal and magnetic flux gradient. This thermomagnetic motion will allow the nanoparticles to crawl on the walls of the container, provoking charge accumulation by means of a triboelectric process, [ 81 ] and experience a temperature variation in time, provoking pyroelectrification. [ 82 ] The device has been tested only in the laboratory and still needs some improvements to be reproduced in a large scale.…”

Density Functional Theory Study of Optical and Electronic Properties of (TiO2)n=5,8,68 Clusters for Application in Solar Cells

“…Titanium dioxide, also known as titania, belongs to the class of transitions metal oxides [26]. TiO 2 has attracted a wide range of interests in the research community owing to its proven ability for many applications in the medical field [27,28], environmental protection [29][30][31], renewable energy [32], etc. TiO 2 is widely employed in solar energy devices, typically used as electron transporting material in nanostructured TiO 2 perovskite-sensitized solar cells and semiconductor in dye sensitized solar cell architecture [18,19,33,34].…”