  Supercapacitors have recently gained popularity as possible energy storage
systems due to their high cycling ability and increased power density. However,
one of the major drawbacks of supercapacitors is that they have a low energy
density, which makes them less effective than batteries. Herein, we explore
different methods of increasing the supercapacitor performance of the
perovskite SrCoO3. We carry out first-principles calculations to systematically
study how SrCoO3/graphene interface, oxygen vacancies, and doping improve the
performance of strontium cobaltite as an anion-intercalation-type
supercapacitor. The results show that the SrCoO3/graphene interface is
relatively stable with a formation energy of 1.3 eV and is highly conductive,
which makes it a promising material for supercapacitors. We also find that
inducing oxygen vacancies in SrCoO3 significantly increases the conductivity of
this material. Results of doping calculations reveal that doping with Mo, V, P,
and Nb all increase the stability and conductivity of SrCoO3. We find that
niobium is the most stable and most conductive of all four dopants. In
addition, we find that vanadium is a very promising novel dopant for SrCoO3 as
an anion-intercalation-type supercapacitor electrode material.
