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The emergency department is a department that is crucial for medical institutions. It is mainly responsible for rescuing critically ill patients and dealing with all kinds of public health emergencies. There are significant differences in the working environment and working mode between the nurses in emergency departments and those of other departments. They tend to come into contact with various occupational risk factors, resulting in high incidence of occupational hazards and accidental injuries. Therefore, it is necessary to analyze the common occupational risk factors of nurses in the emergency department and propose protective measures to ensure that these nurses are able to provide nursing services safely and effectively.

Semiconductor materials have been used for photocatalytic degradation since they were discovered to be useful for photocatalytic degradation. Many studies have been researched to improve the efficiency of photocatalytic degradation. Among them, the introduction of vacancies to improve the photocatalytic efficiency has been verified to be a more feasible method. In this study, we combined two-dimensional (2D) graphite carbon nitride (g-C3N4) nanosheets with oxygen-containing vacancy zero-dimensional (0D) Bi2WO6 (BWO-OV) quantum dots to prepare 2D-0D g-C3N4/Bi2WO6-OV composite catalyst. The use of Bi2WO6 containing oxygen vacancies enhanced the absorption of light and increased the generation of photogenerated carriers. In addition, the formation of heterojunction and the vacancy structure of Bi2WO6 promote the life of photogenerated carriers and improve the catalytic effect of the catalyst. This structure shows high efficiency in removing low concentration (0.5 ppm) of nitric oxide (NO) at room temperature. The efficiency of the composite catalyst is much higher than g-C3N4 or BWO-OV, and better than the composite g-C3N4/Bi2WO6 without oxygen vacancies. When applied to NO removal, the composite g-C3N4/Bi2WO6-OV-10 showed the best catalytic activity which was up to 61.2%. At the same time, five cycles of experiments show that the material has excellent stability.

A series of hollow multi-shelled CeO2 (HoMS-CeO2) support materials with tunable shell numbers were fabricated and applied to the catalytic oxidation of toluene. HoMS-CeO2 possess much higher catalytic activity (T90 = 236 ℃) than hollow CeO2 with only a single shell (h-CeO2) (T90 = 275 ℃). The porous multiple-shelled structure has a higher SBET, which strongly promotes gas distribution and provides more active sites. The superiority of this kind of structure was also verified by comparing h-Co3O4 and HoMS-Co3O4. Furthermore, Pt-Co bimetallic nanoparticles were loaded onto HoMS-CeO2. The synergistic effect between Pt and Co was verified by XPS and O2-TPD, which was observed to allow electron transfer between Pt and Co and thus regulate the electronic state of the Pt. Compared with Pt alone, Pt-Co bimetallic nanoparticles could strongly promote the activation of O2 and oxygen mobility, as revealed by a much higher Oads content and a lower oxygen desorption temperature. Of the catalysts prepared in this study, the 1 wt% PtCo3/CeO2 catalyst was found to be the most suitable for toluene oxidation owing to its excellent activity (T90 = 158 ℃), long-term stability, and water resistance. Finally, in situ DRIFTS was employed to investigate mechanism during toluene oxidation and the possible reaction pathway was proposed.

Sn-TQDs with excellent conductivity were prepared by homogeneously anchoring Sn2+ around Ti3C2 quantum dots as electron mediators for improving the photocatalytic reduction.

The bulk-boundary correspondence is a key concept in topological quantum materials. For instance, a quantum spin Hall insulator features a bulk insulating gap with gapless helical boundary states protected by the underlying Z2 topology. However, the bulk-boundary dichotomy and distinction are rarely explored in optical experiments, which can provide unique information about topological charge carriers beyond transport and electronic spectroscopy techniques. Here, we utilize mid-infrared absorption micro-spectroscopy and pump-probe micro-spectroscopy to elucidate the bulk-boundary optical responses of Bi4Br4, a recently discovered room-temperature quantum spin Hall insulator. Benefiting from the low energy of infrared photons and the high spatial resolution, we unambiguously resolve a strong absorption from the boundary states while the bulk absorption is suppressed by its insulating gap. Moreover, the boundary absorption exhibits a strong polarization anisotropy, consistent with the one-dimensional nature of the topological boundary states. Our infrared pump-probe microscopy further measures a substantially increased carrier lifetime for the boundary states, which reaches one nanosecond scale. The nanosecond lifetime is about one to two orders longer than that of most topological materials and can be attributed to the linear dispersion nature of the helical boundary states. Our findings demonstrate the optical bulk-boundary dichotomy in a topological material and provide a proof-of-principal methodology for studying topological optoelectronics., Comment: 26 pages, 4 figures

A time-reversal invariant two-dimensional (2D) topological insulator (TI) is characterized by the gapless helical edge states propagating along the perimeter of the system. However, the small band gap in the 2D TIs discovered so far hinders their applications. Recently, we predicted that single-layer Bi4Br4 is a 2D TI with a remarkable band gap and that α-Bi4Br4 crystals can host topological edge states at the step edges. Here we report the growth of α-Bi4Br4 nanowires with (102)-oriented top surfaces on the TiSe2 substrates and the direct observation of the predicted topological edge states at the step edges of the nanowires using scanning tunneling microscopy. The coupling between the edge states leads to the formation of surface states at the (102) top surfaces of the nanowires. Our work demonstrates the existence of topological edge states in α-Bi4Br4 and paves the way for developing α-Bi4Br4-based devices for a high-temperature quantum spin Hall effect.

MnO2 nanotubes loaded with Pt and Ni-Fe spinel were synthesized using simple hydrothermal and sol-gel techniques. After loading with Ni-Fe spinel, the specific surface area of the material increases 3-fold. This change helped to provide more active sites and facilitated the association between the catalyst and volatile organic compounds (VOCs). X-ray photoelectron spectroscopy determined that the adsorbed oxygen concentrations were all greatly increased after Pt loading, indicating that Pt promoted the adsorption of oxygen and so accelerated the combustion process. The performance of the catalyst after loading with 2 wt % Pt was greatly improved, such that the T90 for benzene decomposition was decreased to 113 °C. In addition, the 2% Pt/2Mn@NFO exhibited excellent low-temperature catalytic activity when reacting with low concentrations of toluene and ethyl acetate. This work therefore demonstrates a viable new approach to the development of Mn-based catalysts for the low temperature catalytic remediation of VOCs.

Well-designed heterojunction semicounductor coupled with high-conductive cocatalyst can obtain boosted photocatalytic activity. Herein, a novel three-dimensional (3D) hollow heterojunction was prepared by coating the indium zinc sulfide (ZnIn2S4) nanosheets with rich-zinc vacancies (VZn) on 3D hollow titanium carbide (Ti3C2). The obtained 3D hollow heterojunction (Ti3C2@ZnIn2S4) achieved effective optical collection and promoted the separation and transmission of photogenerated carriers as well as the surface reaction of spatial separation. In addition, time-resolved photoluminescence and steady-state photoluminescence spectra indicated that the existence of VZn and the introduction of hollow Ti3C2 spherical shell effectively inhibited the recombination of photogenerated carriers and accelerated their separation and transmission, thus further enhancing the photocatalytic activity. In addition, the introduction of 3D hollow Ti3C2 benefited a larger specific surface area for heavy metal adsorption. Due to the unique structural and compositional characteristics, the heterojunction showed high efficiency of Cr(VI) reduction under visible light. In particular, the optimal Ti3C2@ZnIn2S4 heterojunction (1%-Ti3C2@ZnIn2S4) achieved 100% removal of Cr(VI) within 25 min, with a reaction rate constant of 0.225, which was 8.5 times higher than that of the pristine ZnIn2S4. The superior reusability and structural stability further indicated the MXene-based novel photocatalyst is promising for application in environmental remediation.

The efficient and rapid separation of oil from stabilized oil-in-water emulsions with micro/nanometer size is a global challenge. Owing to the low oil content in oil-in-water emulsions, separating the oil by simply controlling the surface wettability is difficult. Controlling the pore size of the membrane surface to achieve separation will lead to a sharp decrease in flux. Herein, inspired by cell membrane transportation, a hydrophilic/hydrophobic bifunctional Janus membrane for stable oil-in-water separation was prepared by simple surface polymerization and vapor diffusion. The prepared Janus membrane contained a hydrophobic side and hydrophilic polyamine layer. When used for oil-in-water emulsion separation, the polyamine layer accumulated micro/nano-meter oil droplets, forming an oil layer on the hydrophobic surface. Water was retained by the 1 H ,1 H ,2 H ,2 H -perfluorooctyl trichlorosilane layer, allowing oil droplets to selectively permeate through the membrane, achieving the separation effect. As the pore size of the modified fabric was basically unchanged, the permeation flux was fast (1.53×103 Lm−2 h−1). Furthermore, the poly( N , N -dimethylaminoethyl methacrylate) layer destroyed the emulsion stability, making the emulsion droplets aggregate without affecting the separation efficiency with fast permeation flux. Therefore, the prepared bifunctional Janus membrane shows great potential for actual wastewater treatment.

A series of porous Pt/FeₓCey microflowers have been synthesized through a solvothermal method. The well-defined mesoporous structure promotes gas distribution as well as even dispersion of active species, thus exposing more active sites and improving the catalytic efficiency for low-temperature toluene removal. The catalyst composition can be regulated by changing the Fe/Ce molar ratio and Pt loading content. Among the samples, 1 wt % Pt/Fe₃Ce₁ performed the best, with a reaction temperature for 90% toluene conversion of 192 °C at a WHSV of 36,000 mL/(h·g). The synergistic effect of Fe₂O₃ and CeO₂ promotes electron transfer and migration of oxygen species. Addition of Pt enhances the mobility of lattice oxygen, generating a high concentration of active surface lattice oxygen, which facilitates toluene removal. The Mars–van Krevelen model could be applied to explain the mechanism of toluene oxidation over these Fe-based catalysts.

Low mass-transfer efficiency and reaction-driving force make it difficult to realize thorough purification in traditional low-concentration pollutant treatments. Herein, we propose an "adsorption/catalysis in situ" perylene based bifunctional micelle for efficient, accurate and rapid adsorption and catalytic degradation of low-concentration bisphenol A (BPA). They show super-fast (within 10 s), high capacity (448 mg g

An optimized oxygen activity of catalysts can facilitate oxidation of volatile organic compounds. This work shows the first construction of Ce-Co oxide thin-walled nanoboxes. Bulk-phase lattice oxygen is activated by metal-metal interactions. The subsequent uniform dispersion of low loaded Pt nanoparticles further enhances the surface-adsorbed oxygen content, and creates an oxygen-rich reaction interface. Competitive adsorption of water vapor was also inhibited, and complete catalytic oxidation of toluene was achieved at low temperature (T

Capturing radioactive iodomethane and its vapors is a major challenge due to its low adsorption capacity. Herein, we have developed for the first time a pyridine-entrapped elastic crosslinked polysulfate gel (pyridine/TPC-cPS) as an efficient absorbent for iodomethane capture. Each pyridine-encased TPC-cPS network cell acts as a mini-reactor for salt formation between pyridine and iodomethane. The yield reaches up to 96.65 % and traps saturated iodomethane vapor of 1.573 g g

The catalytic room temperature oxidation of formaldehyde (HCHO) is widely considered as a viable method for the abatement of indoor toxic HCHO pollution. Herein, Pt/MnO2 nanoflowers anchored to boron nitride aerogels (Pt/MnO2 -BN) were fabricated for the catalytic room temperature oxidation of HCHO. The three-dimensional Pt/MnO2 -BN aerogels demonstrated superior catalytic activity as a result of the improved diffusion of the reactant molecules within the porous structure. Furthermore, the porous aerogels displayed excellent HCHO adsorption capacities, which promote a rapid HCHO gas-phase concentration reduction and a subsequent complete oxidation of the adsorbed HCHO. The combined adsorption and oxidation properties of the Pt/MnO2 -BN aerogels enhance the oxidative removal of HCHO. The optimized Pt/MnO2 -BN demonstrated excellent catalytic activity toward HCHO (200 ppm) at room temperature, achieving a 96 % formaldehyde conversion after 50 min.

In the field of catalysis, the development of efficient and economical catalysts for the reduction of heavy metals such as Cr(VI) remains challenging. In this study, a series of CuCoOS nanomaterials were successfully prepared by a facile one-step method, and the morphological structures, elemental compositions, and optical properties of the catalysts were characterized in detail. The catalytic performance of each material was evaluated for reduction of a Cr(VI) solution in the dark without any other reagents. The CuCoOS catalyst exhibited excellent activity and completely reduced a 50 ppm Cr(VI) solution within 20 min. This activity could be mainly attributed to the large specific surface area of the prepared catalyst, which had many exposed active sites and defects. Synergy between the two metals (Cu and Co) also facilitated the catalytic reaction. The effects of the catalyst dose, concentration, and pH in the reduction system were studied systematically. Experiments performed by recycling the catalyst confirmed it had good stability and durability. Finally, a possible mechanism for Cr(VI) reduction is proposed.

A new broad-spectrum responsive organic-inorganic hybrid photocatalyst (PI@BWO) was successfully prepared by in-situ growing Bi2WO6 nanosheets onto the surface of π-π stacking perylene imide. The obtained PI@BWO hybrids with different composition exhibited enhanced photocatalytic activity for Bisphenol A (BPA) degradation. Among them, 30% PI@BWO exhibited optimal photocatalytic degradation efficiency, which is 2.6 and 3.9 times higher than that of pristine PI and BWO, respectively. Furthermore, PI@BWO also performed good stability and recyclability. Remarkably, the π-conjugation of PI facilitated the separation of charge carriers and improved the utilization of sunlight for PI@BWO. The introduction of BWO nanosheets also enhanced the adsorption capacity for contaminants and provided much more plentiful active sites, promoting the next photocatalytic reaction. Most importantly, PI@BWO could produce abundant reactive species (such as 1O2 and ·OH) via the charge carrier transfer and energy transfer dual transfer approach, therefore leading to stronger oxidation ability. The photocatalytic degradation mechanism and pathway of the PI@BWO hybrids were finally proposed. Overall, this present work might provide a new insight into the designing and preparation of efficient organic-inorganic hybrid photocatalysts for environmental-friendly removal of hazardous organic pollutants.

The efficient electroreduction reaction of nitrate (NO3−RR) at low concentrations to ammonia is energetically favorable for ammonia production and environmentally essential to treat water contamination. Copper-based conjugated molecule electrocatalysts for the NO3−RR are advantageous in terms of their customizable Cu-coordinative micro-environment and facile preparation; however, they easily agglomerate due to their large π-conjugating system, which severely lowers the active site density and increases the internal resistance. This study demonstrates that Ti3C2Tx MXenes are promising supports to disperse and anchor a molecular catalyst (copper phthalocyanine, CuPc) to construct a CuPc@MXene electrocatalyst in order to significantly promote NO3−RR performance. 10% CuPc@MXene achieved higher ammonia selectivity (94.0%) and higher nitrate conversion (90.5%) compared to those of unsupported CuPc, and retained high ammonia selectivity (∼80%) after seven recycling tests. The combination of online differential electrochemical mass spectroscopy (DEMS) and density functional theory (DFT) calculations has showed that CuPc molecules are able to inhibit the hydrogen evolution reaction and effectively convert nitrate into ammonia through the ONH reaction pathway. The results showed that the MXene support is applicable to many metal phthalocyanines (MPcs, M = Fe, Co, Ni), demonstrating its potential in other electrochemical catalysis applications.

An organic/inorganic core-shell nanobelt, TiO2@V2O5-Polypyrrole (PPy) exhibiting high photocatalytic performance and water-stability was successfully prepared. The heterojunction between the TiO2 nanobelt and V2O5 nanosheets improves both the ability to absorb visible light and the separation efficiency of the photogenerated carrier. When covered with the conjugated polymer PPy, the organic/inorganic nanocomposite absorbs throughout the whole visible light region and exhibits enhanced photocatalytic performance. Due to the outstanding transfer and separation efficiency of the electrons and holes, the new catalytic system is applied to remove water-soluble organic pollutants such as tetracycline (TC), doxycycline and oxytetracycline in high efficiency under visible light irradiation. Moreover, the PPy nanolayer prevents leakage of V2O5, which is beneficial to the construction of a stable heterostructure, and thus the prepared photocatalyst can be recycled. A plausible detailed mechanism for the TiO2@V2O5-PPy photocatalytic system has also been proposed and confirmed. Our work provides a new method for the preparation of inorganic/organic hybrids and their potential application for use in water remediation.

We report an unique 2D/2D Iodine doped BiOIO3/g-C3N4 heterojunction was successfully prepared. The iodine doped BiOIO3 was prepared by a simple solvent exchange method and combined with g-C3N4 by solvothermal method. The prepared photocatalyst has potential application value in the future due to its excellent stable cycle property. BiOIO3 nanoplates and g-C3N4 nanosheets form a close interfacial contact directly, so the catalyst has higher charge transport efficiency and wide visible range due to the introduction of iodide ions. Synergistic heterojunction exhibits strong photocatalytic activity for degradation of NO at ppb-level under visible light, of which 30% Iodine doped BiOIO3/g-C3N4 can achieve a maximum removal rate of 57% for NO. According to the experimental results of ESR and other experiments, a more complex Z-scheme photocatalytic mechanism is proposed, which has stronger redox ability than the traditional mechanism.

A novel crosslinked copolymer, poly(1,4,8,11-cyclotetradecane [2,2-bipyridine]-5,5-dicarboxamine) (PNH), was synthesized in high yield via a simple condensed polymerization at 45 °C. PNH exhibited ...

Oily wastewater, often containing heavy metal ions, is a common source of water pollution. In this study, a modified-MOF-loaded polyacrylonitrile membrane was designed and prepared via solvothermal reaction and electrospinning to simultaneously separate oil-in-water emulsions and adsorb heavy metal ions. The membrane shows superhydrophilicity and superoleophilicity in air and underwater superoleophobicity, which enables the membrane to efficiently separate various oil-in-water emulsions. The strong adsorption capacity of MOF-808 allows this membrane to adsorb heavy metal ions at various concentrations in a short time. The separation efficiency reached 99.97%, and the highest removal efficiency of heavy metal ions reached 97.7%. Additionally, the membrane demonstrated excellent recyclability and corrosion resistance. Overall, the membrane is highly efficient in treating wastewater, and it has great potential for practical applications.

The catalytic activity of well-designed hollow spinel NiCoOx catalysts synthesized using a facile hard template method was investigated. These materials demonstrated higher performance during tolue...

Visible-light-responsive hierarchical Co9 S8 /ZnIn2 S4 tubular heterostructures are fabricated by growing 2D ZnIn2 S4 nanosheets on 1D hollow Co9 S8 nanotubes. This design combines two photoresponsive sulfide semiconductors in a stable heterojunction with a hierarchical hollow tubular structure, improving visible-light absorption, yielding a large surface area, exposing sufficient catalytically active sites, and promoting the separation and migration of photogenerated charges. The hierarchical nanotubes exhibit excellent photocatalytic H2 evolution and CrVI reduction efficiency. Under visible-light illumination, the optimized Co9 S8 /ZnIn2 S4 heterostructure provides a remarkable H2 generation rate of 9039 μmol h-1 g-1 without the use of any co-catalysts and CrVI is completely reduced in 45 min. The Co9 S8 /ZnIn2 S4 heterostructure is stable after multiple photocatalytic cycles.

The p-n junctions composed of ZnO nanosheets and MoS2 nanoparticles were facilely immobilized on Ni foam by two-step electrodeposition method for efficient degradation of organic pollutants through the photoelectrocatalytic (PEC) process. This unique strategy incorporates two semiconductors into p-n heterojunctions on three-dimensional Ni foam substrate, which can enhance visible-light absorption, inhibit the recombination of photogenic charges and expose abundant active sites for photocatalytic oxidation. Thus, the resulting fabricated hybrids (Ni foam@ZnO/MoS2) directly acting as working electrode performs a highly efficient degradation of organic pollutants in water through PEC process that can promote the separation of photogenerated electron-hole pairs under the low applied voltage. In addition, Ni foam@ZnO/MoS2 shows excellent cycling stability and can be easily separated for recycled PEC process, which is advantageous for further application in environmental purification.

Photocatalytic CO

This paper reports the application of NH