  We investigate the electronic instabilities in a Kagome lattice with Rashba
spin-orbital coupling by the unbiased singular-mode functional renormalization
group. At the parent $1/3$-filling, the normal state is a quantum spin Hall
system. Since the bottom of the conduction band is near the van Hove
singularity, the electron-doped system is highly susceptible to competing
orders upon electron interactions. The topological nature of the parent system
enriches the complexity and novelty of such orders. We find $120^o$-type
intra-unitcell antiferromagnetic order, $f$-wave superconductivity and chiral
$p$-wave superconductivity with increasing electron doping above the van Hove
point. In both types of superconducting phases, there is a mixture of
comparable spin singlet and triplet components because of the Rashba coupling.
The chiral $p$-wave superconducting state is characterized by a Chern number
$Z=1$, supporting a branch of Weyl fermion states on each edge. The model bares
close relevance to the so-called $sd^2$-graphenes proposed recently.
