High thermoelectric performance of multiwalled carbon nanotubes based ionogels
Document Type
Article
Publication Date
3-1-2024
Abstract
Ionogels have emerged as promising thermoelectric materials with Seebeck coefficient 2-3 orders of magnitude higher than Seebeck coefficient of their inorganic counter parts. However, they suffer from the problem of low ionic conductivity, which can be improved with the addition of inorganic nanofillers to the ionogels. In the present work, thermoelectric performance of multiwall carbon nanotubes (MWCNTs) based ionogels (IGs) has been investigated. IGs were synthesized via in situ radical polymerization of polyethylene glycol 200 dimethacrylate (PEG200DMA) difunctional monomer in the presence of 1-butyl-3-methyl imidazolium tetrafluoroborate (an ionic liquid) and MWCNTs. Three composites namely MWCNTs-0.25, MWCNTs-0.5 and MWCNTs-1 were prepared having the concentration of MWCNTs by 0.25, 0.5 and 1 wt% respectively. A remarkable 75.3% enhancement in ionic conductivity was achieved for the MWCNTs-1 wt% ionogel compared to the base IG at 40 degrees C. This substantial improvement can be attributed to the ``breathing polymer chain model,'' which describes the dissociation of ion aggregates due to the interaction between the ionic liquid and polymer chains. In terms of thermoelectric performance amongst the MWCNT ionogels, 0.25 wt% MWCNT-based ionogels was the optimized concentration with very high Seebeck coefficient of 1.70 mV/K and power factor of 4.1 mu W/m. K along with excellent thermal stability up to 386 degrees C. These high-performing ionogels hold great promise for efficient utilization of low-grade thermal energy.
Keywords
Ionic Seebeck coefficient, Ionic conductivity, Thermal conductivity, Multiwall carbon nanotubes, Ionogel
Divisions
sch_ecs,mechanical
Funders
Sunway University (STR- RCTR-RCNMET-001-2019),Ministry of Education, Malaysia (FRGS/1/2016/TK10/UM/02/1),King Khalid University King Saud University (RGP.2/303/44)
Publication Title
Materials Today Communications
Volume
38
Publisher
Elsevier
Publisher Location
RADARWEG 29, 1043 NX AMSTERDAM, NETHERLANDS