Novel preparation strategy of graphdiyne (CnH2n-2): One-pot conjugation and S-Scheme heterojunctions formed with MoP characterized with in situ XPS for efficiently photocatalytic hydrogen evolution

As a new two-dimensional (2D) carbon hybrid material, graphdiyne has attracted much attention for its good electrical conductivity, tunable electronic structure and special electron transfer enhancement properties. With its unique atomic arrangement and 2D network of sp and sp2 conjugated hybridization, graphdiyne has a natural advantage in building active catalytic sites. Meanwhile, its special charge distribution gives graphdiyne the ability to be an electron acceptor or donor. Due to its special properties, it has great potential in the field of hydrogen evolution for photocatalytic water decomposition. In this work, a novel strategy for the simple synthesis of graphdiyne (CnH2n-2) by CaC2, hexabromobenzene and mixed organic solvents was firstly prepared and effectively enhanced the photocatalytic hydrogen evolution by topological semimetals (MoP). Combined with experimental tools such as in situ XPS, EPR and DFT calculations, the possible formation of S-Scheme heterojunctions between graphdiyne and MoP is proposed as an important strategy for the application of graphdiyne in the field of photocatalytic hydrogen evolution.