Nanostructured materials have shown extraordinary promise for high surface area applications. Here we report the design of polystyrene (PS)-silicone nanofilaments (SNFs) composites, which can be flexibly grown on various substrates. The high surface area achieved by the SNFs is further extended by grafting with polystyrene. By changing the polymerization conditions and post treatment methods, the morphology of grafted PS is easily tuned into three types: leaf-shaped, bead-shaped and well-wrapped. The tuneable morphology of PS is optimized for oil-water separation and photocatalytic reactions and exhibited improved performances.