Report

Teaser, summary, work performed and final results

Periodic Reporting for period 2 - MAGENTA (MAGnetic nanoparticle based liquid ENergy materials for Thermoelectric device Applications)

Teaser

Today, thermal loss amounts to as much as 20 -50 % of total energy consumption across different industrial sectors and as much as 60-70% in internal combustion engine vehicles. Therefore, if even a small fraction of ‘waste-heat’ can be converted into more useful forms of...

Summary

Today, thermal loss amounts to as much as 20 -50 % of total energy consumption across different industrial sectors and as much as 60-70% in internal combustion engine vehicles. Therefore, if even a small fraction of ‘waste-heat’ can be converted into more useful forms of energy such as electricity, it would lead to reducing considerable amount of energy consumption and to boosting industrial competitiveness. Thermoelectric (TE) materials that are capable of converting heat into electricity have been long considered as a possible solution to recover the low-grade waste-heat from industrial waste-stream, motor engines, household electronic appliances or body-heat. Solid semiconductor-based TE-modules were the first to enter the commercial application, and they still dominate the TE-market today. Despite their technical robustness including long life-time, simple usage involving no moving parts, TE-technology has long been limited mostly to small-power applications due to their low efficiency. Nanotechnology (nano-structuration) of TE materials has led to remarkable improvements in TE-energy conversion capacity in the past 20 years. However, the most promising materials reported in the literature are yet to enter a wide-scale commercial deployment, partly due to their small sizes, substantial production costs and the use of scarce and/or toxic raw materials.

In MAGENTA, we explore an alternative TE-technology using ionic liquid based ferrofluids (colloidal dispersions of magnetic nanoparticles (MNP) in ionic liquids) made of earth abundant and non-toxic materials. The magneto-thermodiffusion of MNPs is believed to enhance the IL’s TE-energy conversion capacity and also gives an additional control parameter; namely, magnetic field. By developing application specific MTE materials and devices, we hope to provide innovation leadership to European companies in waste-heat recovery industries, in particular for the automobile and microelectronic sectors. Furthermore, MAGENTA strives to build an innovation ecosystem around the novel MTE technology, presenting long-term impacts on future renewal energy science and technology.

3 specific objectives of MAGENTA are: Providing foundational knowledge of novel MTE phenomena in IL based ferrofluids, Prototype thermoelectric modules, and Building an innovation ecosystem around the novel MTE technology in the field of waste-heat recovery research and development. To achieve these goals, the project is built upon 5 interacting technical blocks; namely; 1) Material synthesis and characterizations, 2) Magneto-thermoelectric and Magneto-thermodiffusion measurements and 3) Theoretical investigations, 4) Prototype development and 5) Dissemination and exploitation.

Work performed

1) Material Synthesis and characterizations
Among the 1st generation IL-FFs synthesized in the first period, a few were found to be stable up to 200°C. New synthesis protocols have been developed leading to additional, stable IL-FFs. The comprehension on solid-liquid interface has advanced in regards to its effect on MNP clustering and colloidal stability. An improved tuning of MNPs’ magnetic anisotropy through doping has also been demonstrated.
2) Magneto-thermodiffusion and Magneto-thermoelectric measurements.
A high device for studying the MTD behaviour of MNP’s was successfully developed and used to characterize IL-FFs. A varieties of ILs, organic solvents (OS), IL-FFs and their mixtures have been studied for their MTE properties. Notably, the IL-FF based on EMI-TFSI based FF has emerged as the most promising liquid for the TEG applications. EMI-AcO based FF is so far considered as the best candidate for the TCS applications. New investigations to improve the power output (via solvent mixing) have also been initiated.
3) Theory/Simulation
The prediction of Se coefficients in 15000 ILs using the QSPR algorithm has been extended to include cobalt redox salts (in addition to iodine/iodide from previous period) examined in the project. The parameters for MD simulations for modelling the electron conductivity of ILs were identified.
The Se coefficient dependence on the intrinsic magnetic properties of MNPs has been demonstrated. The MNPs physical parameters calculated via MD simulations successfully reproduced experimental results on the MNP assemblies. Additionally, by means of quantum methods (Born-Haber cycle algorithm), the redox potentials of all hypothetically possible redox reactions of all individual ions present in the IL-FF system were calculated; i.e., redox ions, IL-ions, and nanoparticles. Analytically, a linear growth of conductivity with the increase of the colloidal particles concentration has been demonstrated in agreement with experimental findings.
4) Prototyping
The mock-up prototype thermocells have been used extensively for the device optimization for the purpose of building more advanced multi-channel, high-temperature prototype devices. The design and testing have advanced on high-temperature, multi-channel and micro-module devices. Feasibility analysis for the use of TEG modules in ICE vehicles was conducted. Based on these analysis, numerical investigation is started and the designing of the prototype cell is starting.
5) Dissemination
In addition to the project website, Twitter and YouTube accounts were created to reach wider audience. The number of publications have tripled in this period. All of these articles are published in OA journals and deposited in a public repository Zenodo. MAGENTA has also co-organized an international conference with ICTP-UNESCO entitled “Conference on Modern Concepts and New Materials for Thermoelectricity,” in Trieste, Italy, March 2019.

Final results

Beyond-the-state-of-the-art progresses were achieved in all fronts of project’s technical blocks, from material synthesis (new IL-FFs with proven stability at high temperatures), characterizations (magnetism, MTE and MTD properties), comprehension (theoretical and numerical models and simulations) to new prototype thermocell development as detailed above.
Building upon the results obtained in the 1st & 2nd periods, MAGENTA will continue to explore both the fundamental aspect of magneto-thermoelectric phenomena in IL-FFs and the technological aspect of building TE devices. In particular, MAGENTA will achieve following milestones toward the project’s final goals.
• Production novel thermoelectric IL-FFs and their characterizations, and optimization of IL-FFs with superior MTE properties.
• Fundamental knowledge base building through numerical and analytical models describing the physical origins of MTE and MTD effects in IL-FFs.
• Production of 3 traget-specific prototype thermocells; i.e., demonstration (showcasing), micro-scale modules and TEG for internal combustion engine cars.
Due to its foundational character, a new line of R&D activities should follow MAGENTA, to seek enhanced TE effects in ferrofluids. MAGENTA members will continue to participate in popular science events, including showcasing of demonstration prototype thermocell. The social network accounts created in the 2nd period will be utilized to reach a wider audience. As the project mature, the knowledge and skills developed within the project will be exploited to promote technology transfer to targeted industrial sectors, from ionic-liquids and nanofluids manufactures to automobile and mobile (micro) electronics industries, providing head-start competitiveness to European companies.

Website & more info

More info: https://www.magenta-h2020.eu.