Book excerpt: The second volume in a series of handbooks on graphene research and applications Graphene is a valuable nanomaterial used in technology. This handbook features graphene topics related to Physics, Chemistry, and Biology. The Handbook of Graphene, Volume 2 delivers an overview on the numerous and diverse graphene research directions and innovations. The handbook covers a range of areas including graphene in optoelectronic devices and as a detector of biomolecules.