A　mechanical　surface　treatment　is　presented　by　using　adhesive　tape　to　modify　the　surface　morphology　of　graphene　cathodes　and　to　improve　their　field　emission　properties.　The　treated　graphene　cathodes　have　numerous　vertical　sharp　edges,　which　act　as　excellent　field　emission　sites.　Effectively　improved　field　emission　properties　with　low　turn　on　field,　low　threshold　field,　high　emission　current　density　and　high　field　enhancement　factor　are　obtained　due　to　the　full　utilization　of　the　unique　structure　and　excellent　properties　of　graphene.　(C)　2013　Elsevier　B.　V.　All　rights　reserved.