Graphitic carbon nitride (g/C3N4) is of promise as a highly efficient metal‐free photocatalyst, yet engineering the photocatalytic behaviours for efficiently and selectively degrading complicated ...molecules is still challenging. Herein, the photocatalytic behaviors of g/C3N4 are modified by tuning the energy band, optimizing the charge extraction, and decorating the cocatalyst. The combination shows a synergistic effect for boosting the photocatalytic degradation of a representative antibiotic, lincomycin, both in the degradation rate and the degree of decomposition. In comparison with the intrinsic g/C3N4, the structurally optimized photocatalyst shows a tenfold enhancement in degradation rate. Interestingly, various methods and experiments demonstrate the specific catalytic mechanisms for the multiple systems of g/C3N4‐based photocatalysts. In the degradation, the active species, including ·O2−, ·OH, and h+, have different contributions in the different photocatalysts. The intermediate, H2O2, plays an important role in the photocatalytic process, and the detailed functions and originations are clarified for the first time.
The photocatalytic behaviors of g/C3N4 are modified via multiple strategies. The combination of CD‐rGO‐O‐g/C3N4 shows superior activity compared to pristine g/C3N4 and a synergistic effect for photocatalytic degradation of lincomycin both in the degradation rate and the degree of decomposition. In addition, the intermediate, H2O2, plays an important role in the photocatalytic process.
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BFBNIB, FZAB, GIS, IJS, KILJ, NLZOH, NUK, OILJ, SBCE, SBMB, UL, UM, UPUK
Efficient extraction of photogenerated charge carriers is of significance for acquiring a high efficiency for perovskite solar cells. In this paper, a systematic strategy for effectively engineering ...the charge extraction in inverted structured perovskite solar cells based on methylammonium lead halide perovskite (CH 3 NH 3 PbI 3−x Cl x ) is presented. Intentionally doping the chlorine element into the perovskite structure is helpful for obtaining a high open circuit voltage. The engineering is carried out by modifying the aluminium cathode with zirconium acetylacetonate, doping the hole transport layer of nickel oxide (NiO x ) with copper and using an advanced fluorine doped tin oxide (FTO) substrate. This improves the bandgap alignment of the whole device, and thus, is of great benefit for extracting the charge carriers by promoting the transport rate and reducing the trap states. Consequently, an optimized power conversion efficiency of 20.5% is realized. Insights into how to extract charge carriers efficiently with a minimum energy loss are discussed.
The incidence of paediatric fractures among winter sport athletes is not adequately studied. Our objective was to categorize fractures that occurred in paediatric skiers and snowboarders at a single ...ski resort. X-rays of 756 skiers/snowboarders aged 3-17 diagnosed with a fracture were categorized using the Salter-Harris (SH) classification. SH fractures were seen in 158 (21%) patients, with 123 (77%) being Type II. There were no significant differences between patients with a SH fracture and patients with a non-SH fracture for age, sex, snowboarding or skiing, mechanism of injury, terrain or the resort conditions on the day of injury. The most common mechanism of injury was falling onto snow while collisions resulted in more severe injuries. Compared to fractures without growth plate involvement, a higher proportion of SH fractures were seen in the humerus, radius, fibula and thumb; a lower proportion of SH fractures were observed at the tibia and clavicle.
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BFBNIB, GIS, IJS, KISLJ, NUK, PNG, UL, UM, UPUK
Periodic denial-of-service (DoS) attack prevents the information exchange of measurement channel and control channel for switched positive systems through the network. Moreover, the coupling of ...system switching behavior and hybrid behavior due to DoS attack and positive constraint also increase the difficulty in secure control research. The secure control problem of networked switched positive systems under periodic DoS attack is studied and a modeling method based on switching behavior is proposed in this paper. Under variable periodic switching, the multiple linear copositive Lyapunov function is constructed to obtain the positive and asymptotically stable condition for the closed-loop system by limiting the relationship between the switching period and the DoS attack period, and a secure state feedback controller based on the positive system theory is designed, based on which, the constant periodic switching case is also discussed by using the positive system theory. Finally, the validity of the results is
Abstract
Solar water splitting is a promising strategy for the sustainable production of renewable hydrogen and solving the world’s crisis of energy and environment. The third-generation direct ...bandgap semiconductor of zinc oxide (ZnO) with properties of environmental friendliness and high efficiency for various photocatalytic reactions, is a suitable material for photoanodes because of its appropriate band structure, fine surface structure, and high electron mobility. However, practical applications of ZnO are usually limited by its high recombination rate of photogenerated electron–hole pairs, lack of surface reaction force, inadequate visible light response, and intrinsic photocorrosion. Given the lack of review on ZnO’s application in photoelectrochemical (PEC) water splitting, this paper reviews ZnO’s research progress in PEC water splitting. It commences with the basic principle of PEC water splitting and the structure and properties of ZnO. Then, we explicitly describe the related strategies to solve the above problems of ZnO as a photoanode, including morphology control, doping modification, construction of heterostructure, and the piezo-photoelectric enhancement of ZnO. This review aims to comprehensively describe recent findings and developments of ZnO in PEC water splitting and to provide a useful reference for the further application and development of ZnO nanomaterials in highly efficient PEC water splitting.
A new method by water rinse to modify PEDOT:PSS was developed, demonstrating a 16.75% PCE in organic solar cells.
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For the state-of-the-art organic solar cells (OSCs), PEDOT:PSS is the ...most popularly used hole transport material for the conventional structure. However, it still suffers from several disadvantages, such as low conductivity and harm to ITO due to the acidic PSS. Herein, a simple method is introduced to enhance the conductivity and remove the additional PSS by water rinsing the PEDOT:PSS films. The photovoltaic devices based on the water rinsed PEDOT:PSS present a dramatic improvement in efficiency from 15.98% to 16.75% in comparison to that of the untreated counterparts. Systematic characterization and analysis reveal that although part of the PEDOT:PSS is washed away, it still leaves a smoother film and the ratio of PEDOT to PSS is higher than before in the remaining films. It can greatly improve the conductivity and reduce the damage to substrates. This study demonstrates that finely modifying the charge transport materials to improve conductivity and reduce defeats has great potential for boosting the efficiency of OSCs.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
Polymer solar cells have shown good prospect for development due to their advantages of low-cost, light-weight, solution processable fabrication, and mechanical flexibility. Their compatibility with ...the industrial roll-to-roll manufacturing process makes it superior to other kind of solar cells. Normally, indium tin oxide (ITO) is adopted as the transparent electrode in polymer solar cells, which combines good conductivity and transparency. However, some intrinsic weaknesses of ITO restrict its large scale applications in the future, including a high fabrication price using high temperature vacuum deposition method, scarcity of indium, brittleness and scaling up of resistance with the increase of area. Some substitutes to ITO have emerged in recent years, which can be used in flexible polymer solar cells. This article provides the review on recent progress using other transparent electrodes, including carbon nanotubes, graphene, metal nanowires and nanogrids, conductive polymer, and some other electrodes. Device stability is also discussed briefly.
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IZUM, KILJ, NUK, PILJ, PNG, SAZU, UL, UM, UPUK
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