Self-assembled silver nanoparticle films at an air-liquid interface and their applications in SERS and electrochemistry

► We report a novel technology to prepare Ag nanoparticle films at air-liquid interface. ► The morphology of films could be controlled by systematic variation of the experimental parameters. ► The as-prepared films show excellent SERS and electrocatalytic activity. ► The films have potential application in fuel cells, sensors and nanodevices design.