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Exploration of environmental-friendly catalysts is important for acetylene hydrochlorination, due that the traditional HgCl 2 catalyst is highly toxic and harmful to human health. Herein，boron and nitrogen heteroatoms dual doped on oxide graphene (B, N-G) catalyst was synthesized using a model calcination method and applied as a non-metallic catalyst for acetylene hydrochlorination. The B, N-G catalyst shows acetylene conversion significantly higher (nearly 95%) than that of singly B-or N-doped graphenes and a little lower than that of Au and Hg catalyst.Density functional theory calculations and temperature-programmed desorption results indicate that the synthetic effect of B and N doping can promote HCl adsorption, which is the rate-determining step in acetylene hydrochlorination. The excellent catalytic efficiency and relatively low cost of B, N-G makes it a promising catalyst for acetylene hydrochlorination.

A series of highly emissive neutral dinuclear silver complexes [Ag(PPh)(X)](tpbz) (tpbz = 1,2,4,5-tetrakis(diphenylphosphanyl)benzene; X = Cl (1), Br (2), I (3)) was synthesized and structurally characterized. In the complexes, the silver atoms with tetradedral geometry are bridged by the tpbz ligand, and the ends of the molecules are coordinated by a halogen anion and a terminal triphenylphosphine ligand for each silver atom. These complexes exhibit intense white-blue (λ = 475 nm (1) and 471 nm (2)) and green (λ = 495 nm (3)) photoluminescence in the solid state with quantum yields of up to 98% (1) and emissive decay rates of up to 3.3 × 10 s (1) at 298 K. With temperature decreasing from 298 to 77 K, a red shift of the emission maximum by 9 nm for all these complexes is observed. The temperature dependence of the luminescence for complex 1 in solid state indicates that the emission originates from two thermally equilibrated charge transfer (CT) excited states and exhibits highly efficient thermally activated delayed fluorescence (TADF) at ambient temperature. At 77 K, the decay time is 638 μs, indicating that the emission is mainly from a triplet state (T state). With temperature increasing from 77 to 298 K, a significant decrease of the emissive decay time by a factor of almost 210 is observed, and at 298 K, the decay time is 3.0 μs. The remarkable decrease of the decay time indicates that thermal population of a short-lived singlet state (S state) increases as the temperature increases. The charge transfer character of the excited states and TADF behavior of the complexes are interrogated by DFT and TDDFT calculations. The computational results demonstrate that the origin of TADF can be ascribed to (ILCT + XLCT+ MLCT) states in complexes 1 and 2 and(XLCT) states mixed with minor contributions of MLCT and ILCT in complex 3.