  Graphene has recently been attracting considerable interest because of its
exceptional conductivity, mechanical strength, thermal stability, etc.
Graphene-based devices exhibit high potential for applications in flexible
electronics, optoelectronics, and energy harvesting. In this paper, we review
various growth strategies including metal-catalyzed transfer-free growth and
direct-growth of graphene on flexible insulating substrates which are major
issues for avoiding the complicated transfer process that cause graphene
defects, residues, tears and performance degradation of its functional devices.
Recent advances in practical applications based on direct-grown graphene are
discussed. Finally, several important directions, challenges and perspectives
in the commercialization of direct growth of graphene are also discussed and
addressed.
