Amandeep Jindal (Advisor: Prof. S. Basu)

Synthesis of carbon nitride nanofibers by electrospinning using
poly(vinyl) alcohol as supporting polymer as effective electro catalysts
for oxygen reduction reaction in fuel cells.

Electrochemical oxygen reduction reaction (ORR) via nitrogen rich carbon
catalyst materials has the potential for significant cost reduction in
fuel cells. Carbon nitride (CNx) showed inherent catalytic activity for
ORR with low peak current densities due to limited surface area. CNx
nanoparticles embedded in nanofibers were synthesized by electrospinning
using poly(vinyl alcohol) (PVA) as a supporting polymer to augment the
active surface area. It is evident from ORR studies that CNx/PVA
nanofibers has the potential to serve as a cost effective non-metal
catalyst. CNx/PVA nanofibers were studied and characterized using TEM,
SEM, EDX, FTIR, Raman spectroscopy and XPS. Cyclic voltammetry revealed
improved ORR activity of CNx/PVA nanofibers with onset potential
increased from 0.75 V for native CNx nanoparticles to 0.8 V. Significant
improvement in peak current density in LSV studies for ORR of CNx/PVA
nanofibers was also observed. ORR mechanism was further analysed using
RRDE and in-situ FTIR with LSV studies. RRDE analysis confirmed that ORR
primarily takes place via 4-electron pathway. LSV studies for ORR (5000
repetitions) showed significant improvement of catalytic activity of
CNx/PVA nanfibers over a period of time. In-situ FTIR spectroscopy
coupled with linear sweep voltammetry was used to understand the ORR
mechanism over 5000 repetitions.

0500 pm High Tea