Abstract
Tin oxide nanocubes/sulfonated bentonite (SnO2/sBH) nanocomposite blended with acidified poly ether ether ketone (SPEEK) solid state electrolyte is developed for DMFCs. Morphological investigations reveal the existence of SnO2 nanocubes on sheet-like structure of sBH and the uniform dispersion of above composite on SPEEK matrix. The layered sheet-like structure of BH act as heat diffusion barrier and the ceramic feature of SnO2 further improves the thermal stability of a SPEEK membrane. The exposed large surface area of BH and tightly bound water molecules in SnO2 and -SO3H sites increase the water retention properties, which consequently enhance the ionic conductivity of SPEEK/sBH/SnO2 composite membrane. Furthermore, the high aspect ratio of sBH and methanol resistive characteristic of SnO2 lower the methanol diffusion channels in the sBH/SnO2 composite membrane. With the coalition of above significant electrochemical properties, SPEEK/sBH/SnO2 solid electrolyte demonstrates the high DMFC power density and excellent durability, which showers light on the viability of prepared membrane in high performance and durable DMFCs.
The actualization of sBH/SnO2 nanocomposite as an effectual inorganic filler for improving ionic conductivity and limiting methanol permeation of SPEEK membrane is demonstrated for the development of high performance DMFC. [Display omitted]
•SnO2 nanocubes decorated sBH are developed and exploited as nanofillers.•Layered sheets of sBH act as heat diffusion barrier for SPEEK composite membrane.•Tightly bound water molecules in SnO2 and -SO3H facilitate ion transportation.•Effectual interaction among the components ensures continuous ion conduction.•High aspect ratio of sBH and methanol resistive SnO2 limits methanol permeation.•Preferential ion/fuel transportation paths accelerate the DMFC power out-put