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Three pairs of planar chiral heteroarenes were synthesized using palladium-catalyzed Buchwald-Hartwig coupling and hypervalent iodine-mediated oxidative cyclization from optically pure 4-amino[2.2]paracyclophane. Among them, an enantiomer of planar chiral azahelicene was found to have circularly polarized luminescence activity that was remarkably stronger than that of planar chiral heteroarenes.

Two novel 3-D Ln(III)–Cu(I) heterometallic coordination polymers, [Ln2Cu2(L3)4(C2O4)2]·H2O (Ln = Sm, Eu; HL3 = 5-aminonicotinic acid), were hydrothermally produced by reacting lanthanide oxide and copper halide with 5-aminonicotinic acid and orotic acid. In the two isostructural complexes, {Ln6}-wheel clusters link each other via edge-sharing mode, constructing honeycomb-like layers which stack in –ABAB– mode. On the whole, the architectures can be described as sandwich framework constructed by {Ln6}-wheel layers pillared by interlamellar [CuOL32] triangle pillars. The electronic structure was theoretically calculated by the density functional theory, confirming the direct transition character. The steady and transient photoluminescent spectra were measured, from which the intensity parameters, radiative lifetime and quantum efficiency were calculated within the framework of the Judd–Ofelt theory. [Eu2Cu2(L3)4(C2O4)2]·H2O can be regarded as a potential candidate for LED applications.

Planar chiral boron-nitrogen heteroarenes based on [2.2]paracyclophane were successfully synthesized in a few steps as a new family of circularly polarized luminescence emitters. It represents the first case of boron-nitrogen heteroarenes with planar chirality. Those compounds have been demonstrated to exhibit strong circularly polarized luminescence signals and high quantum yields, in both solution and doped film (with glum up to 5.0 × 10-3 and Φsolution up to 73%).

Electrochemical reduction of CO2 (CO2RR) represents a fascinating route for converting atmospheric CO2 to valuable chemicals, and a variety of intermediates are involved in the different CO2RR pathways. However, it has been hampered by the lack of highly effective electrocatalysts so far. Here, the performance of single 3d non-precious transition metals supported on g-C(CN)3 monolayers [TM-C(CN)3, TM = Sc, Ti, V, Cr, Mn, Fe, Co, Ni, Cu, Zn, respectively] as CO2RR electrocatalysts was systematically investigated by using density functional theory (DFT) calculations. The data indicate that all these TM atoms can strongly interact with the g-C(CN)3 substrate, and the TM active sites possess high CO2RR activity and specific selectivity through *OCHO intermediate. Particularly, Sc-, Co–, and Ni-C(CN)3 monolayers are identified as effective CO2RR electrocatalysts due to the low limiting potentials (- 0.28, − 0.42, and − 0.46 V, respectively), whose excellent performances are mainly attributed to the specific TMN3 active sites. Therefore, this work sheds light on g-C(CN)3 monolayer as an excellent supporting material , and will motivate more experimental and theoretical researches to further explore other potential two-dimensional porous carbon-based materials with specific TMN3 active sites for CO2RR.