A novel Ag/ZnO core-shell structure for efficient sterilization synergizing antibiotics and subsequently removing residuals

The massive use of antibiotics has led to the aggravation of bacterial resistance and also brought environmental pollution problems.This poses a great threat to human health.If the dosage of antibiotics is reduced by increasing its bactericidal performance,the emergence of drug resistance is certainly delayed,so that there's not enough time for developing drug resistance during treatment.Therefore,we selected typical representative materials of metal Ag and semiconductor ZnO nano-bactericides to design and synthesize Ag/ZnO hollow core-shell structures(AZ for short).Antibiotics are grafted on the surface of AZ through rational modification to form a composite sterilization system.The research results show that the antibacterial efficiency of the composite system is significantly increased,from the sum(34.7%+22.8%-57.5%)of the antibacterial efficiency of AZ and gentamicin to 80.2%,net synergizes 22.7%,which fully reflects the effect of 1+1>2.Therefore,the dosage of antibiotics can be drastically reduced in this way,which makes both the possibility of bacterial resistance and medical expenses remarkably decrease.Subsequently,residual antibiotics can be degraded under simple illumination using AZ-self as a photocatalyst,which cuts off the path of environmental pollution.In short,such an innovative route has guiding significance for drug resistance.

Trifunctional Cu-Mesh/Cu_(2)O@FeO Nanoarrays for Highly Efficient Degradation of Antibiotic, Inactivation of Antibiotic-Resistant Bacteria, and Damage of Antibiotics Resistance Genes

Trifunctional Cu-mesh/Cu_(2)O@FeO nanoarrays heterostructure is designed and fabricated by integrating CuCu_(2)O@FeO nanoarrays onto Cu-mesh(CM)via an in situ growth and phase transformation process.It is successfully applied to efficiently mitigate the antibiotic pollution,including degradation of antibiotics,inactivation of antibiotic-resistant bacteria(ARB),and damage of antibiotics resistance genes(ARGs).Under visible-light irradiation,CM/CuCu_(2)O@FeO nanoarrays exhibit a superior degradation efficiency on antibiotics(e.g.,up to 99%in 25 min for tetracycline hydrochloride,TC),due to the generated reactive oxygen species(ROS),especially the dominant·O^(2−).It can fully inactivate E.coli(HB101)with initial number of~108 CFU mL^(−1) in 10 min,which is mainly attributed to the synergistic effects of 1D nanostructure,dissolved metal ions,and generated ROS.Meanwhile,it is able to damage ARGs after 180 min of photodegradation,including tetA(vs TC)of 3.3 log 10,aphA(vs kanamycin sulfate,KAN)of 3.4 log 10,and tnpA(vs ampicillin,AMP)of 4.4 log 10,respectively.This work explores a green way for treating antibiotic pollution under visible light.

A novel structure of quasi-monolayered NiCo-bimetal-phosphide for superior electrochemical performance

Bimetallic transition metal phosphides(TMPs)as potential candidates for superior electrochemical performance are still facing great challenges in the controllable preparation of two-dimensional(2 D)structures with high aspect ratio.Herein,a novel structure of quasi-monolayered NiCo-bimetal-phosphide(NiCoP)has been designed and successfully synthesized by the newly developed process combined with ultrasonic-cavitation and phase-transition.This is the first time to break through the controllable preparation of 2 D bimetal-phosphides with a thickness of 0.98 nm in sub-nanoscale.Based on the advantages of 2 D quasi-monolayer structure with dense crystalline-amorphous interface and the reconfigured electronic structure between Ni^(δ+)/Co^(δ+)and P^(δ-),the optimized Ni_(5%)CoP exhibits an outstanding bifunctional performance for electrocatalyzing both hydrogen evolution reaction and oxygen evolution reaction in an alkaline medium.Ni_(5%)CoP presents lower overpotentials and voltage of 84 mV&259 mV and1.48 V at the current density of 10 mA cm^(-2)for HER&DER and overall water splitting,respectively,which are superior to most other reported 2 D bimetal-phosphides.This work provides a new strategy to optimize the performance of electrolytic water for bimetal-phosphates and it may be of significant value in extending the design of other ultrathin 2 D structured catalysts.

SnNi nanoneedles assembled 3D radial nanostructure loaded with SnNiPt nanoparticles： Towards enhanced electrocatalysis performance for methanol oxidation

A desirable methanol oxidation electrocatalyst was fabricated by metal atom diffusion to form an alloy of an assembled three-dimensional （3D） radial nanostructure of SnNi nanoneedles loaded with SnNiPt nanoparticles （NPs）.Herein,metal atom diffusion occurred between the SnNi support and loaded Pt NPs to form a SnNiPt ternary alloy on the catalyst surface.The as-obtained catalyst combines the excellent catalytic performance of the alloy and advantages of the 3D nanostructure;the SnNiPt NPs,which fused on the surface of the SnNi nanoneedle support,can dramatically improve the availability of Pt during electrocatalysis,and thus elevate the catalytic activity.In addition,the efficient mass transfer of the 3D nanostructure reduced the onset potential.Furthermore,the catalyst achieved a favorable CO poisoning resistance and enhanced stability.After atomic interdiffusion,the catalytic activity drastically increased by 45%,and the other performances substantially improved.These results demonstrate the significant advantage and enormous potential of the atomic interdiffusion treatment in catalytic applications.

An ultrahigh-sensitivity and selective sensing material for ethanol： α-/γ-Fe2O3 mixed-phase mesoporous nanofibers

A process for synthesizing Fe2O3 based on electrospinning and the hard-template method was proposed such that the crystal phase of Fe2O3 could be tailored with precision. Mesoporous γ-Fe2O3, α-/γ-Fe2O3, and α-Fe2O3 nanofibers could be fabricated successfully by changing the synthesis parameters. Scanning electron microscopy, transmission electron microscopy, X-ray diffraction analyses, Raman spectroscopy, and nitrogen adsorption-desorption analyses were used to characterize the structures of the synthesized products. The optimal calcination conditions for preparing α-/γ-FeaO3 nanofibers with the highest ethanol response were determined through ethanol-sensing measurements. The mixed-phase material exhibited a significantly higher sensitivity than the corresponding purephase ones. The superior ethanol-sensing performance of the α-/γ-Fe2O3 nanofibers suggested that they may be suitable for use in alcohol sensing. Hence, a novel strategy for improving the sensing performance of metal oxide semiconductors is to assemble the different crystalline forms of the same metal oxide in one structure. Finally, the mechanism responsible for the sensing performance of α-/γ-Fe2O3 being higher than those of γ-Fe2O3 and α-Fe2O3 was elucidated on the basis of data from X-ray photoelectron spectroscopy and resistance measurements.

Layered CuNi-Cu_(2)O/NiAlO_(x) nanocatalyst for rapid conversion of p-nitrophenol to p-aminophenol

In order to well arrange active sites and avoid byproducts, the reasonable structured carrier nanocatalyst plays a crucial role in high catalytic performance, but still remains a challenge. Herein, the layered CuNi-Cu_(2)O/NiAlO_(x) nanosheets have been constructed through hydrothermal synthesis followed by calcination and H_(2) reduction treatment process. The in-situ formed CuNi nanoalloys (NAs) and nano-Cu_(2)O were evenly distributed on the bilateral surface of layered NiAlOx nanosheets. Based on the planar structure of nanosheet, the synergy between catalytic active CuNi NAs and photocatalytic active nano-Cu_(2)O endows CuNi-Cu_(2)O/NiAlO_(x) nanosheets with rapid conversion efficiency for catalyzing p-nitrophenol (p-NP, 14 mg·L^(−1)) to p-aminophenol (p-AP) in 32 s with the reaction rate constant k up to 0.1779 s−1, and no obvious performance decay can be observed even over 27 cycles. Moreover, high concentration of p-NP at 10 and 20 g·L^(−1) could be reduced to p-AP within 14 and 20 min, respectively. Such designed nanoalloy/bimetal-oxide heterostructure can provide a solution for rapid conversion of aminoaromatics from nitroaromatics wastewater even at a large concentration range.

Hollow nanostructure of sea-sponge-C/SiC@SiC/C for stable Li^(+)-storage capability

For the purpose of stable performance in energy storage systems, a new hollow nanostructure of seasponge-C/SiC@SiC/C(SCS/SiC@SiC/C) has been successfully fabricated by the SCS/SiC nanospheres coated with SiC/C shells through an in situ reduction process. Based on SCSs and the carbon shells, the stable hollow structures of SCS/SiC@SiC/C can contain large proportion of active SiC layers, which are adhered to both SCSs and the inner surfaces of carbon shells. Such nanostructured anode enables an excellent cycling stability with a capacity of 612 mAh/g at a current density of 0.5 A/g after 1,800 cycles, achieving an excellent stable Li^+-storage capability.

Two‑Level Biomimetic Designs Enable Intelligent Stress Dispersion for Super‑Foldable C/NiS Nanofiber Free‑Standing Electrode

Due to the lack of in-depth understanding about the folding issues of the electronic materials,it is a huge challenge to pre-pare a super-foldable and highly electrochemical faradic electrode.Here,inspired from from the fully nimble structures of cuit cocoons and cockscomb petals,with two-level biomimetic design,for the first time we prepared a super-foldable and electrochemically functional freestanding cathode,made of C-fiber@NiS-cockscomb(SFCNi).In virtue of its nimble biomi-metic structures,SFCNi can remarkably sustain over 100,000 times,repeated true-folding without composite fibers fracture,functional matters detachment,conductivity degradation,or electrochemical performance change.The main mechanism behind these behaviors was disclosed by Real-time scanning electron microscopy and mechanical simulations,on the folding process.Results unveil that the cockscomb-like NiS with atomic thickness can deform freely due to the need of bending,and the cuit-cocoon-like SFCNi can generate an“ε-shape”folding structure at the crease.Such a smart self-adaptive deforma-tion capability can effectively reduce the effect of stresses and local excessive deformations,so that the chemical bonds can preserve their interaction,and the material won’t fracture.This subtle and exceptional mechanical behavior realizes a super-foldable property.The two-level biomimetic design strategy is a novel method for fabrication of super-foldable composite electrodes and integrated multi-functional super-foldable devices.

A New Discovery of Calcium Phosphate Urinary Stones Formation Induced by Melamine: Nanocrystalline Assembly Mechanism

Melamine (Mel),a contaminant that has received much attention in recent years,has been adulterated into milk powder,causing a large number of infants suffering from kidney stone disease.To study the process and mechanism of calcium phosphate (CAP)stone formation induced by Mel,we simulated the formation process of CaP stones and studied the effect of Mel on crystallization in aqueous and synthetic urine systems,respectively.Ion selective electrode method was used to study the thermodynamic parameters and reaction rate of the crystallization process.It was firstly discovered that Mel could induce the formation of CaP crystals significantly under weak acidic urine conditions in which CaP cannot be stably present,so it may cause people to produce CaP stones.Thermodynamic parameter and reaction rate analysis indicated that Mel could increase the reaction tendency and accelerate the formation of CaP crystals,which was achieved by two process of electrostatic adsorption and release of calcium ions.This research is expected to provide scientific guidance for the prevention and treatment of Mel-related stones.