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Three-dimensional (3D) hierarchical microspheres of Bi12O17Cl2 (BOC) were prepared via a facile solvothermal method using a binary solvent for the photocatalytic degradation of Rhodamine-B (RhB) and Bisphenol-A (BPA). Co3O4 nanoparticles (NPs)-decorated BOC (Co3O4/BOC) heterostructures were synthesized to further enhance their photocatalytic performance. The microstructural, morphological, and compositional characterization showed that the BOC microspheres are composed of thin (~20 nm thick) nanosheets with a 3D hierarchical morphology and a high surface area. Compared to the pure BOC photocatalyst, the 20-Co3O4/BOC heterostructure showed enhanced degradation efficiency of RhB (97.4%) and BPA (88.4%). The radical trapping experiments confirmed that superoxide (•O2−) radicals played a primary role in the photocatalytic degradation of RhB and BPA. The enhanced photocatalytic performances of the hierarchical Co3O4/BOC heterostructure are attributable to the synergetic effects of the highly specific surface area, the extension of light absorption to the more visible light region, and the suppression of photoexcited electron-hole recombination. Our developed nanocomposites are beneficial for the construction of other bismuth-based compounds and their heterostructure for use in high-performance photocatalytic applications.

In the past few years, the all-solid lithium battery has attracted worldwide attentions, the ionic conductivity of some all-solid lithium-ion batteries has reached 10−3–10−2 S/cm, indicating that the transport of lithium ions in solid electrolytes is no longer a major problem. However, some interface issues become research hotspots. Examples of these interfacial issues include the electrochemical decomposition reaction at the electrode-electrolyte interface; the low effective contact area between the solid electrolyte and the electrode etc. In order to solve the issues, researchers have pursued many different approaches. The addition of a buffer layer between the electrode and the solid electrolyte has been at the center of this endeavor. In this review paper, we provide a systematic summarization of the problems on the electrode-solid electrolyte interface and detailed reflection on the latest works of buffer-based therapies, and the review will end with a personal perspective on the improvement of buffer-based therapies.

Carbon-based materials have attracted extensive interest in metal-ion batteries owing to their low cost, good conductivity, and environmental friendliness. The practical application of graphite materials is associated with trade-offs in cyclability and energy density due to the sluggish kinetics. Herein, nitrogen-doped chain-like carbon nanospheres (NCN) with expanded interlayer distance are effectively fabricated by annealing carbon derived from aniline combustion. More impressively, the resulting NCN exhibits a chain-like structure and pyrrolic-N-dominated nitrogen doping, which not only facilitates charge transport but also provides chemically active sites for Zn- and K-ion storage. The above features lead to ultrafast ion storage in the NCN electrode via redox pseudocapacitive reactions, which endows NCN with enhanced kinetics and dramatic electrochemical performance: a remarkable energy density of 124.1 W h kg−1 for zinc-ion storage; superior reversible capacity (363.4 mA h g−1 at 0.1 A g−1), robust rate capability (120.3 mA h g−1 at 10 A g−1) and excellent cycling performance (193.8 mA h g−1 after 1000 cycles at 1 A g−1) for potassium-ion storage.

Three-dimensional (3D) hierarchical microspheres of Bi

In recent years, a temperature-sensitive hydrogel was reported as a promising draw agent in forward osmosis (FO) technology. PEG, acts as porogen, as an enabler to improve the swelling property of hydrogels. From FO test, the addition of porogen to the hydrogel can improve the water flux of FO by increasing the swelling properties of the hydrogel. And the hydrogel modified with porogen improves the concentration efficiency of wastewater from 1.09 to 1.124 times, indicating that the modification of the hydrogel by the porogen has positive significance for FO technology. In this study, an advanced hydrogel was synthesized via physical copolymerization by using N-isopropylacrylamide and sodium acrylate. The internal structure was investigated by SEM test where it was found that that porogens have different mechanisms of action on hydrogel performance: Porogen affects the swelling property of hydrogel by changing the internal network structure through physical “occupation”. The effect of porogen concentration is to act on the porosity of hydrogel, while the main effect of the molecular weight of porogen on the hydrogel structure is by altering the pore size.

The Z-scheme BiVO4/α-Fe2O3 photocatalyst was synthesized by a simple hydrothermal method. The photocatalyst is composed of α-Fe2O3 nanocubes with a regular cubic structure and the BiVO4 particles distributed on the surface of the α-Fe2O3 nanocubes. The photocatalytic performance of Z-scheme BiVO4/α-Fe2O3 photocatalyst was investigated in terms of its capacity for photodegradation of tetracycline hydrochloride. Improved photocatalytic activity was observed for Z-scheme BiVO4/α-Fe2O3 photocatalyst compared with pure BiVO4 and α-Fe2O3 nanocubes under visible light irradiation. Studies of its morphology, physicochemical properties and photoelectrochemical behaviors demonstrated that BiVO4 loading on the surface of α-Fe2O3 nanocubes forms a Z-scheme heterojunction, which increases the specific surface area and significantly promotes the separation of photoinduced carriers. The main active species were determined to be OH and h+ by ESR technique and trapping experiments. We propose a possible photocatalytic mechanism of Z-scheme BiVO4/α-Fe2O3 photocatalyst system. This study may also provide a novel and eco-friendly demonstration of a useful strategy for the design and preparation of special structure photocatalytic materials.

Problematic fouling along with wetting of membrane represent the main barriers for large-scale application of this technology. To solve the above problems and reinforce the anti-pollution and anti-wetting features of the distilling membrane, a brand-new TiO2 nanorods and 1H,1H,2H,2H-perfluorodecylsilane-triethoxy (PDTS) modified alumina hollow ceramic membrane with superhydrophobic surface and self-cleaning property was prepared for utilization in the vacuum membrane distillation. To synthesize the novel membrane, a seed layer was supported on the hollow ceramic membrane by the immersion-calcination method. Then, the TiO2 nanorods were grown on the membrane by hydrothermal method and annealed to strengthen the crystal structure. Finally, the nanorod-grown membrane was immersed in an alcohol solution of PDTS for hydrophobic treatment. The resulted modified membrane was applied to the distillation process to treat 100 g L−1 of concentrated brine for 3 h. It was revealed that the modified membrane possessed with a lower ionic conductivity under 20 µs.cm−1 of the permeated liquid and desirable surface superhydrophobicity at appropriate water contact angle of 152°, thus showing great promise for use in the membrane distillation process.

Luminescent solar concentrators (LSCs) provide a transformative approach to integrating photovoltaics into a built environment. In this paper, we report thin-film LSCs composed of intramolecular charge transfer fluorophore (DACT-II) and discuss the effect of two polymers, polymethyl methacrylate (PMMA), and poly (benzyl methacrylate) (PBzMA) on the performance of large-area LSCs. As observed experimentally, DACT-II with the charge-donating diphenylaminocarbazole and charge-accepting triphenyltriazine moieties shows a large Stokes shift and limited re-absorption losses in both polymers. Our results show that thin-film LSC (10 × 10 × 0.3 cm3) with optimized concentration (0.9 wt%) of DACT-II in PBzMA gives better performance than that in the PMMA matrix. In particular, optical conversion efficiency (ηopt) and power-conversion efficiency (ηPCE) of DACT-II/PBzMA LSC are 2.32% and 0.33%, respectively, almost 1.2 times higher than for DACT-II/PMMA LSC.

Lower cellular elasticity is a distinguishing feature of cancer cells compared with normal cells. To determine whether cellular elasticity differs based on cancer cell type, cells were selected from three different cancer types including breast, cervix, and lung. For each cancer type, one counterpart normal cell and three types of cancer cells were selected, and their elasticity was measured using atomic force microscopy (AFM). The elasticity of normal cells was in the order of MCF10A > WI-38 ≥ Ect1/E6E7 which corresponds to the counterpart normal breast, lung, and cervical cancer cells, respectively. All cancer cells exhibited lower elasticity than their counterpart normal cells. Compared with the counterpart normal cells, the difference in cellular elasticity was the greatest in cervical cancer cells, followed by lung and breast cancer cells. This result indicates lower elasticity is a unique property of cancer cells; however, the reduction in elasticity may depend on the histological origin of the cells. The F-actin cytoskeleton of cancer cells was different in structure and content from normal cells. The F-actin is mainly distributed at the periphery of cancer cells and its content was mostly lower than that seen in normal cells.

We report blue to green emission mechanoluminescence (ML) in CaZnOS:Bi3+,Li+with about 50 times greater ML intensity than that of the strong ML material ZnS:Cu+. The ML spectrum showed an intense emission band peaking at 485 nm and a red-shift of about 9 nm on increasing the stress or friction. In addition, the preferable threshold of CaZnOS:Bi3+,Li+ was below 1 N due to its excellent strain sensitivity. The depths of the traps responsible for ML were estimated to be in the range of 0.68–1.2 eV. The as-prepared CaZnOS:Bi3+,Li+ phosphors were successfully used for the fabrication of homemade ink and flexible thin films, which could be further used for anticounterfeiting and stress mapping. These findings reveal its great potential for application in an advanced anticounterfeiting technology and visualization of stress distribution for damage diagnosis due to its ultra-high efficiency, low threshold and color tunability.

The growth mechanism and the corresponding kinetic parameters are valuable to improve the electrodeposition method for preparing Pt-based catalysts. In this paper, the effect of the operation condition on the electrodeposition mechanism has been investigated through experiments and theoretical analysis, and the corresponding kinetic parameters were acquired. The catalytic activity of the deposited Pt catalyst prepared by the pulse current (PC) electrodeposition method was improved, compared with that of the commercial Pt catalyst and the Pt catalyst prepared by the direct current electrodeposition method. The results show that both high current density and high ton/toff in PC electrodeposition could cause large cathode overpotentials, resulting in faster nucleation rate and smaller catalyst particle size, which leads to the better reaction activity of the Pt catalyst. Finally, kinetic parameters including the constants, which relate the nucleation rate with the overpotential, the transfer coefficient and the exchange current density of the electrodeposition process, were determined.

To solve the problems of membrane material tolerance and membrane fouling, a micro/nano hierarchial structure with low surface energy was constructed above the exterior surface of a ceramic hollow fiber membrane using ZnO nanorod arrays and 1H,1H,2H,2H-perfluorodecyltriethoxysilane (PDTS) coatings, which make it superhydrophobic and self-cleaning. The surface morphology, chemical functional groups, and water contact angel of the modified membranes were identified. The results show that large quantity of ZnO nanorods possess desirable characteristics (i.e. superhydrophobicity, exceptional thermal and mechanical stability, and water contact angle of 160.12°) were detected on the ceramic membrane. The novel membrane shows excellent self-cleaning performance and good desalination ability in the utilization of vacuum membrane distillation (VMD) system for high-salinity water desalination.

Increasing interest and applications for graphene and carbon-based films emphasize the need for economical synthesizing techniques. We report a facile and novel synthesis method to prepare graphene, graphitic carbon, graphitic carbon nitride composite layers depending upon the spin-coated poly(methyl methacrylate) (PMMA) polymer layer and substrate used. Few and multilayer graphene sheets were formed on SiO2 covered Si substrate using a simple rapid thermal annealing process. We examined hot plate and rapid thermal annealing using a nickel capping layer and found that the rapid thermal process converted PMMA into graphene efficiently. The resultant graphitic films were characterized using FESEM, HRTEM, XRD and Laser Raman. Current–voltage response of the prepared graphene layers was analyzed fabricating as two terminal devices. The thickness of the formed layer depended on PMMA layer thickness, and the metal capping layer was crucial for converting PMMA into graphene. This polymer conversion method to fabricate graphene layers will be attractive for many graphene applications due to its versatility. Keywords: Graphene, Graphitic carbon, Graphitic carbon nitride, Poly(methyl methacrylate), Polymer, Rapid thermal annealing

Herein, the pulse temperature is provided during the nucleation period of the nanoparticles to shorten the nucleation time for Pt-based nanoparticle growth. Herein, 3-nm-sized Pt-Ni alloy octahedral catalysts were prepared by pulse-like hydrothermal method. The influence of the pulse on nucleation is demonstrated by comparing the morphology obtained from the conditions of constant temperature and pulse temperature. It has been found that pulse temperature could decrease the nucleation time, and the final morphology of the nanoparticle is different due to the different growth temperatures and times. When used in oxygen reduction reaction, the octahedron Pt-Ni exhibited a 50 mV positive shift of the half-wave potential and the mass-specific activity and area-specific activity are 5 and 7 times higher than that of commercial 40% Pt/C at 0.9 V. Through this way, kinds of multiple alloy compounds could be composed with less time in the future.

In recent years, one-dimensional (1D) transition-metal chalcogenide nanowires have been considered as potential candidates to replace noble-metal-based electrocatalyst in water electrolysis because...

This paper mainly focuses on the optimization and design of cathode catalyst layer structure for low-Pt loading membrane assembly electrode. When Pt loading at cathode increased from 0.025 mg cm−2 to 0.4 mg cm−2, the apparent current density of electrode increases gradually, while the electrochemical active surface area (ECSA) and the utilization rate of catalyst show a downward trend. As Pt loading at cathode keeps at 0.1 mg cm−2, commercial Vulcan XC-72 carbon are doped into the conventional Pt/C catalyst layer to improve the utilization rate of the catalyst. The results show that the optimum doping carbon content leads to ∼2 times increase of the thickness of the cathode catalyst layer, and achieves a 32.93% increase of ECSA and better durability than that of conventional catalyst layer. Meanwhile, gas transport in the catalyst layer becomes more difficult with the increase of the amount of doping carbon. Based on this, a more stable Vulcan XC-72@PTFE particles are prepared and selected to construct internal gas transport channels under the same carbon content. The surface contact angle of the catalyst layer is obviously increased to 118.4°. The hydrophobicity of the cathode catalyst layer is enhanced, and the oxygen gain voltage is significantly reduced. The peak power density of PEMFC reaches 539 mW cm−2, which is 30.57% higher than that of one with a conventional catalyst layer structure. Therefore, this work provides a good way for the preparation of high-performance and durable cathode catalyst layer for low-Pt loading membrane assembly electrode.

We report alkali metal-assisted growth of monolayer molybdenum disulfide (MoS2) by chemical vapor deposition. Single-layer MoS2 flakes with high-quality and large-scale (>∼200 μm) are successfully fabricated on alkali metal-coated SiO2 substrates. On the other hand, particle-like MoS2 tends to grow on bare SiO2 substrates. Detailed growth process of layered MoS2 with surface-coated alkali metal is suggested. A series of experimental and theoretical results indicate that alkali metals play a role in strong surface adsorption and re-supply of molybdenum precursor to the growth surface during lateral growth of MoS2. We believe that our results will provide fruitful information for large-scale or selective-area growth of single-layered transition metal dichalcogenides.

Monodispersed Eu, Mn co-doped β-NaYF4 nano-crystals with various morphologies, including nanoplates, hexagonal nanoprisms and microrod, have been prepared via a facile hydrothermal route. The trisodium citrate (Cit3−) and pH values, rather than Mn2+, play an important role in fine-tuning the morphologies. A broad band emission from the 5d-4f transition of Eu2+ as well as line emissions from the 4f-4f transitions of Eu3+ are observed in Eu, Mn co-doped β-NaYF4. The quantum efficiency of Eu3+ was improved from 16% to 72% by inhibiting the luminescence of Eu2+. In addition, controllable emissions from Eu3+/Eu2+ can be achieved through the incorporation of Mn2+ in β-NaYF4. The correlation between the tunable emission and enhanced quantum efficiency with Eu3+/Eu2+ and Mn2+ in β-NaYF4 has been established and discussed in detail.

We report here a simple alternative method for measuring charge carrier drift mobilities in semiconductor devices. A typical falling photocurrent transient formula for switch-off-state was adjusted to obtain simultaneously electron and hole mobilities. For both undoped ZnO film and InAlAs/InGaAs quantum well structure, electron mobilities extracted from our model were compared with those obtained from maximum-entropy mobility-spectrum analysis method (ME-MSA). Our results demonstrated that electron mobility obtained from our photocurrent response model could serve as substitutes for a representative mobility obtained from ME-MSA.

The tunable of fluid transport on solid surface plays a significant role for self-cleaning and drug-saving fields. It effectively prevents the corrosion and declines the fluid resistance induced by the rushing water and accumulated microorganisms on the hull surface. To more effectively combat these problems, herein, we provide a new strategy, a superhydrophobic shark-fin-like bionic surface. Anisotropic characteristic of this novel structure lead to the different de-pinning force in the opposite direction for the water droplet. The superhydrophobicity of the shark-fin-like embossment is from the "air layer" formed by the ZnO nano-structure. This novel composited surface can effectively realize the directional droplet-actuation and fluid-resistance reduction performance. Droplets and fluid will move more easily along the special direction on the shark-fin-like surface. Moreover, the substrate material is flexible and easy to mass production. We believe that this work will give a significant scientific insight to self-cleaning surface and hull design.