Layered van der Waals (vdW) materials, while exhibiting vast interface areas prone to contamination, can spontaneously coalesce interfacial contaminants into larger, easily removable nanopockets. This study demonstrates this coalescence and proposes an elastocapillary cleaning mechanism involving both elastic and capillary forces. The mechanism is elucidated through control of nanopocket morphology and coalescence via mechanical stretch, showcasing bilayer graphene's self-renewal capabilities.