TY - JOUR
T1 - Application of a water-soluble cobalt redox couple in free-standing cellulose films for thermal energy harvesting
AU - Taheri, Abuzar
AU - MacFarlane, Douglas R.
AU - Pozo-Gonzalo, Cristina
AU - Pringle, Jennifer M.
PY - 2019/2/20
Y1 - 2019/2/20
N2 - Thermal energy harvesting using thermoelectrochemical cells (thermocells) is a sustainable method to produce electricity without carbon dioxide emissions. The solvent and redox couple used in the electrolyte play an important role in determining both the safety and performance of thermocells, and development of leak-free electrolytes with high performance is particularly important for transportable devices. Here, the application of aqueous and non-aqueous electrolytes containing the [Co(bpy)] 2+/3+ redox couple in both liquid and solid forms was studied. Cellulose was used as an environmentally friendly material for solidification of the different liquid electrolytes. The properties and performance of the new aqueous [Co(bpy)] 2+/3+ electrolytes was compared to those containing the Fe(CN) 6 3−/4− couple, both in liquid and quasi-solid state electrolytes. Higher diffusivity for the cobalt redox ions was observed in the aqueous electrolyte compared to the non-aqueous electrolytes, while the Seebeck coefficient of the redox couple, which determines the open circuit voltage of the thermocell, was largest in the organic solvents. No significant effect of solidification on the Seebeck coefficient was observed.
AB - Thermal energy harvesting using thermoelectrochemical cells (thermocells) is a sustainable method to produce electricity without carbon dioxide emissions. The solvent and redox couple used in the electrolyte play an important role in determining both the safety and performance of thermocells, and development of leak-free electrolytes with high performance is particularly important for transportable devices. Here, the application of aqueous and non-aqueous electrolytes containing the [Co(bpy)] 2+/3+ redox couple in both liquid and solid forms was studied. Cellulose was used as an environmentally friendly material for solidification of the different liquid electrolytes. The properties and performance of the new aqueous [Co(bpy)] 2+/3+ electrolytes was compared to those containing the Fe(CN) 6 3−/4− couple, both in liquid and quasi-solid state electrolytes. Higher diffusivity for the cobalt redox ions was observed in the aqueous electrolyte compared to the non-aqueous electrolytes, while the Seebeck coefficient of the redox couple, which determines the open circuit voltage of the thermocell, was largest in the organic solvents. No significant effect of solidification on the Seebeck coefficient was observed.
KW - Cobalt redox couple
KW - Hydrogel
KW - Solid electrolyte
KW - Thermal energy harvesting
KW - Thermocell
UR - http://www.scopus.com/inward/record.url?scp=85059314446&partnerID=8YFLogxK
U2 - 10.1016/j.electacta.2018.11.208
DO - 10.1016/j.electacta.2018.11.208
M3 - Article
AN - SCOPUS:85059314446
VL - 297
SP - 669
EP - 675
JO - Electrochimica Acta
JF - Electrochimica Acta
SN - 0013-4686
ER -