Molecular and Crystal Structure of 1,3,5-Tris(benzimidazol- 1-ylmethyl)-2,4,6-Trimethylbenzene

The compound 1,3,5-tris(benzimidazol-1-ylmethyl)-2,4,6-trimethylbenzene, crystallizes in the monoclinic system, space group P21/c, with a = 17.571(4), b = 10.860(2), c = 14.126(3) ?; ( = 92.89(3)(, V = 2692(1) ?3, Dc = 1.260 g/cm3, Z = 4, C33H30N6, Mr = 510.63, ((MoK() = 0.077mm-1, F (000) = 1080. The structure was refined to R = 0.0592, wR = 0.1379 for 1492 (I(2((I)) reflections. The title molecule has cis, trans, trans-conformation about the central phenyl ring. The screw-related molecules are connected by hydrogen bonds C-H(((N (x, -0.5-y, 0.5+z) and form the infinite helical chains. The polar molecular chains are antiparallelly stacked through edge-to-face C-H…πinteractions.

Design of AIEgen-based porphyrin for efficient heterogeneous photocatalytic hydrogen evolution Special Collection:Aggregation-Induced Processes and Functions

Tetraphenylethylene(TPE)-conjugated porphyrin TPE-ZnPF is synthesized in high yield and characterized by single-crystal X-ray diffraction.The propeller-shaped TPE groups not only enable exceptional aggregation-induced emission(AIE)in the solid state but also abolish the strongπ-πstacking of porphyrin moieties and thus prohibit aggregation-caused quenching(ACQ).TPE-ZnPF aggregates feature longlived photoexcited states,which subsequently suppress non-radiative decay channels and enhance emission intensity.Moreover,its aggregates show more efficient lightharvesting ability due to the Förster resonance energy transfer from the TPE energy donor to the porphyrin core energy acceptor,well-defined nanosphere morphology,and more efficient photoinduced charge separation than the porphyrin Ph-ZnPF,which possesses ACQ and agglomerated morphology.As a result,an excellent photocatalytic hydrogen evolution rate(ηH_(2))of 56.20 mmol g^(‒1)h^(‒1)is recorded for TPE-ZnPF aggregates,which is 94-fold higher than that of the aggregates of Ph-ZnPF(0.60 mmol g^(‒1)h^(‒1))without the TPE groups.

Steering S-scheme charge transfer via interfacial dipoles induced by amine-containing polyelectrolytes

The lack of a robust interfacial driving source over multicomponent photocatalysts is an essential contributor to the sluggish spatial charge transfer across the heterointerface and severe carrier recombination,thereby rendering maneuvering charge transfer of composite materials a thorny issue.Herein,we demonstrate an electric dipole moment-driven charge transfer photosystem utilizing amine-containing polyfluorene polyelectrolyte(i.e.,PFN)and inorganic semiconductor matrices(i.e.,WO_(3))as the building blocks to direct the interfacial charge transfer,effectively targeting the photoexcited charge carriers to the active sites.Experimental results and theoretical simulations reveal that the electronic coupling interaction between the pendant electron-rich amine groups along the PFN backbone and WO_(3)surface enables the nonuniform charge distribution at the interface over the WO_(3)@PFN heterojunction,which ultimately fosters the formation of interfacial dipoles oriented from conjugated macromolecular backbone of PFN to the surface of WO_(3)matrices.The interfacial dipoles with excellent charge transfer kinetics spontaneously activate the unidirectional and accelerated S-scheme charge motion from the WO_(3)framework to the conjugated chain of PFN due to the suitable band offsets at the interface,thus endowing WO_(3)@PFN heterostructures with a significantly enhanced net efficiency of photoactivity.These findings would provide some insights into the design of advanced heterojunction photocatalysts for solar energy conversion as well as the study of the working mechanism of polyelectrolyte interlayers in optoelectronic devices.

An overview on AIEgen-decorated porphyrins:Current status and applications

One of the major obstacles of porphyrins is the aggregation-caused quenching(ACQ)of photoluminescence due to the strong intermolecularπ–πinteraction of the planar porphyrin core in the solid state.However,ACQ leads to the nonradiative deactivation of the photoexcited states which results in short-lived charge-separated states and thus low photoluminescence and singlet quantum yields.This phenomenon would limit the utilization of porphyrins in near-infrared fluorescent bioimaging,photodynamic therapy,photocatalytic hydrogen evolution,electrochemiluminescence,and chiroptical applications.Hence,to address the ACQ property of porphyrins and enhance the performance of the above applications,a limited number of AIEgen-decorated porphyrins have been designed,synthesized,and tested for their applications.It has been found that the introduction of AIEgens,such as tetraphenylethylene,diphenylacrylonitrile,(3,6-bis-(1-methyl-4-vinylpyridinium)-carbazole diiodide,and iridium motif into the porphyrin core,transformed the porphyrins from ACQ to aggregation-induced emission(AIE)in their solid state due to the reduced strong intermolecularπ–πstacking of porphyrins.Consequently,such porphyrins containing AIE features are employed as potential candidates in the above-mentioned applications.In this review,we summarize the AIEgen-decorated porphyrins which have been published to date,and also discuss the benefits of converting porphyrins from ACQ to AIE for enhanced performance within each application.As far as we know,there is no review that summarizes the structures and applications of AIEgen-decorated porphyrins to date.Therefore,we presume that this review would be helpful to design more efficient AIEgen-decorated porphyrins for a wide range of applications in the future.