Chemical Modification and Functionalization of Graphdiyne

Graphdiyne features sp and sp 2 hybridized carbon atoms.The direct natural band gap and Dirac cone structure for graphdiyne are believed to originated from inhomogeneous π-bonding of differently hybridized carbon atoms and overlap of carbon 2pz orbitals.The special electronic structures and pore structures of graphdiyne are responsible for its potential and important applications in the fields of information technology, electronics, energy, catalysis, and optoelectronics.Recent basic and applied research studies of graphdiyne have led to important results; as a result, graphdiyne has become a new research field for carbon materials.The high activity of acetylenic units in graphdiyne provides a good platform for chemical modification and doping.Several approaches have been developed to modify the band gap of graphdiyne, including invoking strain, BN-doping, preparing nanoribbons, and hydrogenation, leading to a new graphdiyne (GDY) or graphyne (GY) derivatives.In this review, we summarize the recent progress in nonmetallic heteroatom doping, especially by nitrogen, boron, or oxygen; by modifying metal atoms for tuning electronic/spintronic properties, enhancing water splitting performance, and applying dye-sensitized solar cells and catalysts; and by surface functionalization of graphdiyne via hydrogenation, hydroxylation, and halogenation to adjust the band gap.Hence, it can be surmised that the electronic structures of graphdiynes can be tuned for specific applications.These results suggest that graphdiynes can be more advantageous than grapheme for tailoring energy band gaps for application in nanoelectronics.We also discuss the influence of doping and functionalization on the electronic properties of graphdiyne and their effects on the synergistic enhancement of photoelectrocatalytic performance.We hope that the deep and wide application of these new materials in many fields such as energy transfer and storage, catalyst, electronics, gas separation, and spintronics will draw much attention and become a widely focused research direction.