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.
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
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.
Phase pure and well-dispersed FeS2 quantum dots (QDs) have been synthesized with a method combining hot-injection and solvothermal reaction at a relatively low temperature. Hybrid composites composed ...of organic semiconductor and FeS2 QDs effectively dissociates excitons at the donor–acceptor interface, which qualifies efficient bulk-heterojunction solar cells. It has been found that the photovoltaic performance depends greatly on different ways of ligands exchange. It shows that mercaptopropanoic acid (MPA) treated hybrid thin film performs better in solar cells efficiency than pyridine exchange treatment to as-synthesized FeS2 nanoparticles due to a suppressed current leakage.
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•A new method has been developed to synthesize FeS2 QDs at a low temperature.•FeS2 QDs obtained in our work are well crystallized and monodispersed.•Photon-generated excitons are efficiently splitted at the polymer:FeS2 QDs interface.•MPA treatment to the hybrid thin film enables better photovoltaic performance.•Our reaction process is adaptable in synthesis of some other nanocrystals.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UL, UM, UPCLJ, UPUK
Manipulating stimulated‐emission processes and overcoming the ohmic loss of metals in plasmonic lasers are of significance for the according applications in biological sensors, data storage, ...photolithography, and optical communications. Herein, through utilizing an electrochemical‐assisted growth method for high‐quality perovskite nanowires, plasmonic lasers based on the structure of metal/dielectric layer/perovskite nanowires are constructed. The plasmonic lasers demonstrate a threshold of 62 µJ cm−2, a high quality factor of Q ≈ 655, and a fast lasing decay time of 1.6 ps. Interestingly, the plasmonic lasers present an attractive capability in transformation from single mode to multiple modes just by adjusting the pumping energy. In addition to the broad stoichiometry‐dependent tunability of the perovskite materials, the proposed plasmonic lasers have great promise in real applications.
Plasmonic lasers based on the structure of metal/dielectric layer/perovskite nanowires are constructed via an electrochemical‐assisted growth method for high‐quality perovskite nanowires. The plasmonic lasers demonstrate a threshold of 62 µJ cm−2, a high quality factor of ≈655, and a fast lasing decay time of 1.6 ps. The laser modes can be effectively manipulated by adjusting the pump energy.
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FZAB, GIS, IJS, KILJ, NLZOH, NUK, OILJ, SBCE, SBMB, UL, UM, UPUK
Lead halide perovskites have gained tremendous attentions in many fields, especially in nanolasers, owing to the excellent optoelectronic properties. However, the underlying lasing mechanism is not ...clear in both plasmonic and photonic nanolasers at room temperature. Here, the plasmonic lasers and the photonic counterparts based on organic–inorganic hybrid lead tri‐bromine perovskite nanowires are achieved at room temperature and are compared in terms of lasing evolution, lasing wavelengths, and lasing dynamics. The same spectra evolution and the same emission wavelength indicate that the plasmonic and the photonic CH3NH3PbBr3 nanowire lasers have the same gain origination. The calculated Mott density lower than the threshold density and lasing photon energy lower than exciton energy prove that an electron–hole plasma contributes to both the two types of lasing actions from perovskite nanowires at room temperature. The work deepens the understanding of underlying mechanism of perovskite nanowire lasers.
An electron–hole plasma is responsible for the plasmonic and photonic lasing in single‐crystal CH3NH3PbBr3 nanowires at room temperature owing to lower emission energy than exciton resonance and the higher threshold density than the Mott density.
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FZAB, GIS, IJS, KILJ, NLZOH, NUK, OILJ, SBCE, SBMB, UL, UM, UPUK
Zinc oxide flower-like bunches were directly synthesized on indium-doped tin oxide (ITO) glass substrates through a simple chemical bath deposition process. By adjusting precursor concentration, ...other morphologies (spindles and rods) were also obtained. All of them are hexagonal and single crystalline in nature and grow along the 0001 crystallographic direction. The possible growth mechanisms for these nano- and microcrystals were proposed. It was revealed that both the inherent highly anisotropic structure of ZnO and the precursor concentration play crucial roles in determining final morphologies of the products. In addition, vibrational properties of ZnO crystals with different morphologies were investigated by Raman spectroscopy.
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IJS, KILJ, NUK, PNG, UL, UM
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