Highlights •A new route for efficient and high-yield production of F-diamane-like nanosheets.•Using expanded graphite allows uniform dispersion of F atoms in the carbon lattice.•The exfoliation of expanded fluorinated graphite can be readily achieved.•Mild sonication produced F-diamane-like nanosheets up to micrometers in size.•Pre-exfoliation/fluorination and sonication is suitable for large-scale preparation.