Temporal Down-sampling based Video Coding with Frame-Recurrent Enhancement

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NiSx Quantum Dots Accelerate Electron Transfer in Cd_0.8Zn_0.2S Photocatalytic System via an rGO Nanosheet “Bridge” toward Visible-Light-Driven Hydrogen Evolution

Minimizing the charge transfer barrier to realize fast spatial separation of photoexcited electron–hole pairs is of crucial importance for strongly enhancing the photocatalytic H₂ generation activity of photocatalysts. Herein, we propose an electron transfer strategy by reasonable design and fabrication of high-density NiSx quantum dots (QDs) as a highly efficient cocatalyst on the surface of Cd_0.8Zn_0.2S/rGO nanosheet composites. Under visible-light irradiation, the formation of a two-dimensional (2D) Cd_0.8Zn_0.2S/rGO nanohybrid system with 2 wt % NiSx loading gave a prominent apparent quantum efficiency (QE) of 20.88% (435 nm) and H₂ evolution rate of 7.84 mmol g^–1 h^–1, which is 1.4 times higher than that of Pt/Cd_0.8Zn_0.2S/rGO. It is believe that the introduced rGO nanosheets and NiSx QDs obviously improved the interfacial conductivity and altered the spatial distribution of electrons in this nanoarchitecture. Thus, the synergistic effects of interfacial junctions result in a regulated electron transportation pathway along the basal planes and ultrafast transfer and spatial separation of photoexcited carriers, which are responsible for the enhanced photocatalytic performance. This work gives a facile and effective strategy to understand and realize rationally designed advanced photocatalysts for high-efficiency, stable, and cost-efficient solar hydrogen evolution applications

Crystal Growth, Intermolecular Noncovalent Interactions, and Photoluminescence Properties of Halogenated Phthalic Anhydride-Based Organic Charge Transfer Cocrystals

Organic charge-transfer cocrystals are composed of an electron-rich donor molecule and an electron-deficient acceptor molecule, which are bonded together by intermolecular noncovalent interactions such as π–π interactions, hydrogen bonds, halogen bonds, and charge-transfer interactions. These noncovalent interactions influence the cocrystal packing structures and the photoluminescence properties. Herein, four charge transfer cocrystals, pyrene-tetrafluorophthalic anhydride (TFPA), perylene-TFPA, pyrene-tetrachlorophthalic anhydride (TCPA), and perylene-TCPA, were grown by the slow cooling method and the influence of intermolecular noncovalent interactions on the photoluminescence properties were investigated. Cocrystals of pyrene-TFPA and pyrene-TCPA exhibit a yellow rod-like morphology, while both perylene-TFPA and perylene-TCPA exhibit red rod-like shapes. Results indicate that the C–H···X (X = F, Cl, or O) interactions, π–π interactions, and charge-transfer interactions are dramatically affected by the energy difference between the HOMO of the donor and the LUMO of the acceptor. Meanwhile, for the same acceptor molecules, the positions of the photoluminescence peaks of the cocrystals red-shifted with the enhancement of weak noncovalent interactions, which paved the way to tuning the optical properties of charge transfer cocrystals