Lignin, cellulose and hemicellulose are the major components of biomass. The chemical reactivities of the biomass are affected by the difference in chemical structures making the knowledge of their composition, essential to predict the efficiency of the biomass conversion process for utilizing bio-energy, which is of immense importance for successful commercialization of these processes and thus to gain energy security. Despite the presence of accurate and robust Wet Chemical methods, it is very difficult to implement these techniques commercially. Therefore, in this study the chemical composition of biomass has been determined by a simpler physical technique-Thermogravimetric Analysis (TG). The values obtained were correlated with chemical methods and it was found that TG predicted the holocellulose content with a relatively high accuracy while it underestimated the lignin content by a huge margin. The kinetic parameters of degradation of five biomass samples have also been reported in this study. This study also compared the mass loss profiles of the biomass in TG with their mass loss profiles in a furnace.

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The physicochemical properties and proton conductivity are two important parameters of an effective polymer electrolyte membrane for a high-temperature fuel cell (HTPEMFC) (120 °C–180 °C). In this work, a novel composite membrane is prepared by poly (2, 5-Benzimidazole) (ABPBI) polymer matrix together with phosphonated multiwall carbon nanotube (PMWCNT) using the solvent casting method. The membrane typically exhibits fin-like projections due to the addition of PMWCNTs as characterised by SEM micrographs. The membrane also demonstrates enhanced proton conductivity and mechanical strength of 0.16 S cm−1 and 33 MPa respectively compared to pristine doped ABPBI membrane. Interestingly, the fabricated membrane is found to absorb the acid 2.15 times the pristine membrane whereas, acid leaching out per unit absorbed acid is reduced by 2.17 times compared to that of pristine membrane. Open circuit potential of 0.87 V with a fuel cell assembled with the composite membrane underlines better control on fuel crossover delivering a peak power density of 275.0 mW cm−2 compared to 212.8 mW cm−2 for the pristine membrane. Such enhancement in the power density (∼30%) is thus observed by tuning the polymer electrolyte hybrid nanocomposite membrane properties through functionalisation.

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