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Artificial photosynthesis converting carbon dioxide into chemical fuels with a high added value is a promising solution to both fossil fuel shortage/pollution and global climate change; however, the development of highly efficient photocatalysts toward this goal is still largely bereft of fresh ideas. Herein, we propose a "cascade electron transfer" strategy through spurring both interfacial and inner electron transfer rates for a 0D/2D photocatalyst of CsPbBr3/CuTCPP metal organic framework (MOF). Upon photoexcitation, the heterojunction structure with an appropriate band alignment facilitates an ultrafast interfacial electron transfer rate of 1.4 ps from CsPbBr3 segment to CuTCPP MOF and subsequent ultrafast internal electron transfer of 21 ps from CuTCPP ligand to the Cu node within the enlarged 2D framework. The efficient electron transfer ensures efficient charge separation favorable for photocatalytic reactions: The photocatalyst exhibits an outstanding yield of 47.2 μmol g−1 h−1 (CO and CH4 combined) superior to previous reports. Rational design of hierarchical heterojunctions with matching electronic bandgap not only expedites cascade charge transfer but also prevents holes from recombining with electrons or oxidizing the photocatalysts without the necessity of sacrificial reagents. This work thus provides useful insight for boosting photocatalytic efficacy from a dynamic perspective. [ABSTRACT FROM AUTHOR]

The design of novel catalytic materials towards sustainable energy production and storage is important for tackling energy shortage and environmental issues. Here, we report the preparation of cobalt nanoparticles encapsulated by a nitrogen doped carbon nano-onion (Co-NCNO) and their applications in the oxygen reduction reaction (ORR) and lithium-ion batteries (LIBs). Co-NCNO was prepared by one-step carbonization using an imidazolium ionic liquid as the carbon and nitrogen source. An in situ transmission electron microscope (in situ TEM) was used for the real time investigation of the carbon nano-onion formation process during a heating process from 450 °C to 850 °C. When applied to the ORR, Co-NCNO-850 exhibited high activity with a half-wave potential of 767 mV in 0.1 M KOH solution and high structural stability. Density functional theory (DFT) simulation indicates that the cobalt enhances the adsorption of reaction intermediates on the nitrogen doped carbon surface. Furthermore, Co-NCNO-850 also exhibited excellent performance for LIBs with a specific capacity of 774 mA h g−1 at a current density of 0.5C after 500 cycles. The ionic liquid assisted synthesis of Co-NCNO opens a new avenue for the efficient fabrication of hybrid nano-catalysts for energy applications. [ABSTRACT FROM AUTHOR]

The emergency of surface defect would significantly influence the quality of MPCG (Mobile Phone Cover Glass). Therefore, efficient defect detection is highly required in the manufacturing process. Focusing on the problem, an automatic detection system is developed in this paper. The system adopts backlight imaging technology to improve the signal to noise ration and imaging effect. Then, a modified segmentation method is presented for defect extraction and measurement based on deep neural networks. In the method, a novel data generation process is provided, with which the drawback that huge amount of data is required for training deep structured networks can be overcome. Finally, experiments are well conducted to verify that satisfactory performance is achieved with the proposed method. [ABSTRACT FROM AUTHOR]

Natural hollow fibers were used as templates to in situ produce thin Cs4PbX6 nanosheets on the inner walls, forming luminescent fibers that integrated the advantages of the large length of fibers and the emission tunability of perovskites, and exhibited great robustness as well for multiple applications like warning signs, anti-counterfeiting and fashion. [ABSTRACT FROM AUTHOR]