Movable
devices such as mobile phones, laptops etc., have need of energy and power
but simultaneously the functioning charging lifetime of these power sources is
not being improved in agreement with the user demand. In the previous era, the use
of liquefied fuels in devices has been a substitute and fascinating field of
research 1, 2. Primarily, wide efforts have been made on direct methanol fuel
cells (DMFCs) owing to their performance, high energy density, and easy accessibility
of fuel by slight contaminant emissions and efficient energy conversion 3. Though,
the commercial use of DMFCs is restricted because of certain serious complications
such as (i) process at controlled concentration, (ii) deprived kinetics owing
to catalyst poisoning through carbon intermediates produces in methanol
oxidation, causing in reduced fuel performance (iii) at room temperature
activity is very low 4-6, (iv) methanol crossover, which confines the usage
of high methanol
concentrations, normally less than 2 M 7 and lastly (v) the expensive Pt (Pt
is precise catalyst for the DMFCs). To overcome all of above mentioned problems,
DFAFCs have attained attention in current time. Formic acid is  comparatively less poisonous than other liquid
fuels and it has very high open circuit potential (1.450 V) theoretically than
direct formic acid fuel cells (1.190 V) and proton exchange membrane fuel cells (1.229 V) 8.
Moreover, Formic acid also has a lower crossover flux as compared to methanol
and ethanol over nafion, or the proton exchange membrane, because of the
repulsion existing by the membrane terminal groups. Therefore it accelerates
proton transport in the anodic part of the fuel cell which leads to high energy
conversion 9. Although, the energy density of formic acid is 2086 WhL-1
which is smaller as compared to methanol (4690 WhL-1), it transmits additional
energy per unit volume as compared to methanol owing to the fact that concentrated
formic acid (20 M or 70 wt %) can be used as a fuel comparatively low
concentration of methanol (2 M) 10. The further main benefit of formic acid
to use as a fuel is its creation from environmental leftover by the biomass conversion
procedures 11.