Preparation and characterization of PVDF/nonwoven fabric flat-sheet composite membranes for desalination through direct contact membrane distillation

► PVDF flat-sheet composite membranes were prepared for membrane distillation. ► Influence of non-solvent additives on membranes characteristics was investigated. ► The membrane presented excellent permeability and performance stability. ► The membrane surface properties were studied by atomic force microscope. ► The prepared flat-sheet membrane had a narrow pore size distribution.