  The intricate interaction between the deformability of a substrate and the
dynamic spreading of a liquid drop on the same, under the application of an
electrical voltage, has remained far from being well understood. Here, we
demonstrate that electrospreading dynamics on soft substrates is dictated by
the combined interplay of electrocapillarity, the wetting line friction and the
viscoelastic energy dissipation at the contact line. Our results reveal that
during such electro-elastocapillarity mediated spreading of a sessile drop, the
contact radius evolution exhibits a universal power law in a substrate
elasticity based non-dimensional time, with an electric potential dependent
spreading exponent. Simultaneously, the macroscopic dynamic contact angle
variation follows a general power law in the contact line velocity, normalized
by elasticity dependent characteristic velocity scale. Our results are likely
to provide the foundation for the development of a plethora of new applications
involving droplet manipulations by exploiting the interplay between
electrically triggered spreading and substrate-compliance over interfacial
scales.
