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[Display omitted] • PVA/GO@PMPC nanofibrous membranes were prepared and used for removal of ciprofloxacin hydrochloride. • The maximum adsorption capacity was reached at pH = 7.0. • Adsorption mechanism involved hydrogen bonding interactions, π-π interactions and electrostatic interactions. • The developed nanofibrous membranes displayed excellent reusability. In this study, zwitterionic polyelectrolyte brushes poly(2-methacryloyloxyethyl phosphorylcholine) (PMPC) were grafted on poly (vinyl alcohol)/graphene oxide (PVA/GO) nanofibrous membranes by surface-initiated activators generated by electron transfer for atom transfer radical polymerization (AGET ATRP). The obtained PVA/GO@PMPC nanofibrous membranes were used as adsorbents for removal of ciprofloxacin hydrochloride. The membrane prepared with the most amount of GO in the electrospinning solution and the highest MPC concentration during grafting polymerization displayed the largest adsorption amount of ciprofloxacin hydrochloride (245.6 mg/g). Within 15 h, the adsorption achieved equilibrium, and the removal process agreed well with pseudo-second-order kinetic model. At pH = 7.0, the maximum adsorption capacity was attained, and the adsorption capacity increased gradually with temperature. Study on adsorption mechanism revealed that π-π interactions, hydrogen bonding interactions and electrostatic interactions might be involved for removal of ciprofloxacin hydrochloride. After being repeatedly used for six times, binding affinity of the membrane did not change significantly. This study provided a general method for creating nanofibrous membranes with superior adsorption performance for removal of organic pollutants. [ABSTRACT FROM AUTHOR]

[Display omitted] • A new "NH 3 -free" synthesis of thin carbon-shelled CrN nanoparticle is designed. • 1,2,4-1H-triazole is used as a metal-chelating agent and nitrogen/carbon source. • The hybrid structure is applicable to Cobalt-doped CrN. • The d band of CrN can be manipulated by metal doping. • The Co-CrN@C delivers a greater power density and cyclability than Pt/C in AEMFC. Hydrogen fuel cells are expected to be widely used in transportation and portable power generation. Unfortunately, sluggish cathodic oxygen reduction reaction (ORR) kinetics hamper the commercial application of the fuel cells. The quest for cost effective and highly efficient ORR catalysts is of great importance. Transition metal nitride (TMN) has received widespread attention mainly for its Pt-like characteristics. Here, we propose a new one-step "NH 3 -free" synthesis of thin-carbon-shell-encapsulated binary cobalt chromium nitrides (Co-CrN@C) using 1,2,4-1H-triazole as the nitrogen/carbon source. The Co-CrN@C exhibits almost ideal four-electron reduction of oxygen and achieves remarkable long-term durability and better methanol tolerance due to high-degree graphitization of the carbon shell. The X-ray photoelectron spectra and the density functional theory calculations unveil the origin of the intrinsic activity of the catalyst and the reaction mechanism. Furthermore, Co-CrN@C exhibits an impressive peak power density (PPD) of 488 mW cm−2, surpassing the 423 mW cm−2 for the Pt/C-driven anion exchange membrane fuel cells. These findings offer an indispensable strategy for rational design of high-efficient and durable non-noble catalysts. [ABSTRACT FROM AUTHOR]

[Display omitted] • By depositing Al/a-Al 2 O 3 /Al tri-layer coating on depleted uranium, diffusion pathways of corrosion medium are elongated with misalignment of columar grain boundaries in Al coatings. • The a-Al 2 O 3 interlayer can suppress accumulation and facilitate outgassing of Ar bubbles as major growth defects in Al coatings. • Introduction of intermixing layers between Al- and UO 2 -rich interfacial regions can enhance anti-corrosion stability of Al/a-Al 2 O 3 /Al tri-layer coating. As important energy materials, uranium and its alloys have been widely used in the fields of material sciences and nuclear industrial applications. Applying metal and/or ceramic surface protective coatings can effectively retard easy corrosion of uranium with extremely high chemical activity. In principle, ideal surface protective coatings should possess (1) lowered density of elongated diffusion pathways (i.e. grain boundaries and growth defects) and (2) improved interfacial bonding to substrate by preventing corrosion medium from reacting with uranium. In this work, we have demonstrated that by magnetron-sputtering amorphous Al 2 O 3 (a-Al 2 O 3) interlayers within Al coatings on depleted uranium (DU), the corrosion resistance is significantly improved as indicated by corrosion potential datum DU substrate (−645 mV), DU with mono-layer Al coating (−610 mV) and DU with Al/a-Al 2 O 3 /Al tri-layer coating (−550 mV). Diffusion pathways are elongated with misalignment of columnar grain boundaries in Al coatings around a-Al 2 O 3 interlayers. Meanwhile, density of diffusion pathways is lowered since a-Al 2 O 3 does not contain conventional crystal defects, and can suppress accumulation and facilitate outgassing of Ar bubbles as major growth defects. The effect of coating/substrate interfacial bonding on corrosion behavior is investigated by introduction of intermixing layers between Al- and UO 2 -rich interfacial regions. A strategy to improve anti-corrosion stability of Al/a-Al 2 O 3 /Al tri-layer coating by optimizing degree of intermixing is proposed. The present findings may shed lights on compositional and microstructural design of anti-corrosion coatings on uranium and its alloys. [ABSTRACT FROM AUTHOR]

[Display omitted] • The precisely grown Al 2 O 3 via ALD technique enabled a controllable polymerization in growth of PDA on Si. • The void spaces and carbon layers were simultaneously manipulated in the synthesis of Si/C composites. • An ultrahigh Si content of 89.3 wt% with a large reversible capacity of 2583 mAh g−1 and a long cycle life over 1000 times at 2 A g−1 was realized in optimal Si/C anode materials. • This unique structure accommodated huge volume expansion/shrinkage of Si, boosted reaction kinetics upon lithiation/delithiation, and suppressed parasitic reactions on active surface against volatile electrolytes. The carbon coating strategies, ameliorating structure instability and reaction kinetics of silicon anodes upon lithiation/delithiation, have been chronically plagued by an electrochemical contradiction between a high specific capacity from a high silicon content and a long cycle life from a high carbon content. Herein, the carbon coating layers and void structures for silicon/carbon composites were simultaneously manipulated through a precisely grown Al 2 O 3 template, which induced a controllable polydopamine polymerization through its mild interfacial interaction with Tris-buffer solution and created abundant void spaces by its residual parts. Particularly, the as-optimized silicon/carbon composite with an ultrahigh silicon content of 89.3 wt% could demonstrate a large initial reversible capacity of 2583 mAh g−1 with an 82.1 % coulombic efficiency at 200 mA g−1, a remarkable cycling durability of 601 mAh g−1 after 990 cycles at 2000 mA g−1, and an excellent rate capability of 887 mAh g−1 at 4000 mA g−1. The uniform void structures could maintain the structural stability/integrity of silicon, boost reaction kinetics across electrode/electrolyte interfaces, and suppress the uncontrollable formation/evolution of solid electrolyte interphases upon cycling. This novel research on synchronously regulating carbon layers and void structures in silicon/carbon composites would enlighten a rational development of high-capacity and long-life silicon anodes. [ABSTRACT FROM AUTHOR]

Figures (a) and (b) demonstrate that the Pt NPs were successfully modified on the MCNO-based detector after annealing at 750 °C. The Pt NPs had a diameter of 5–10 nm, which is within the typical size range of quantum dots, thus allowing them to be considered as quantum dots. Pt NPs modification of MCNO film resulted in a remarkable ratio of 73, which is approximately 4.1 times higher than the ratio without Pt NPs modification. This excellent result can be attributed to three factors. Firstly, the barrier created between the NPs and the film reduces the dark current by blocking the transport of carriers. Secondly, the plasma resonance effect of the Pt NPs increases the incident light intensity. Lastly, the extinction of the NPs enhances the absorption of incident light and reduces the surface resistance, leading to a high photocurrent enhancement. These results demonstrate that Pt NPs modification plays a critical role in improving the photoproperties of MCNO-based detectors. [Display omitted] • High quality MCNO films had been deposited on Si substrates by RF magnetron sputtering. • High vacuum in situ annealing plays a critical role in the properties of MCNO-based detectors. • High vacuum in situ 750 °C annealing resulted in a 7.61 on/off ratio for MCNO-based detectors. • Pt nanoparticles modification significantly improved on/off ratio of the device to 38.51. The work developed a series of infrared detectors based on the Mn-Co-Ni-O (MCNO) films, which were grown using a radio frequency (RF) magnetron sputtering technique. It was observed that the characteristics of MCNO films were significantly impacted by the annealing temperature. Elevating the in-situ annealing temperature from 550 to 750 °C improved the performances of MCNO films. Additionally, it was found that in situ annealing was more advantageous than ex-situ annealing of 750 °C for the properties of MCNO films. The response value (light to dark) increased from 2.5 to 17.7 at 15 V bias, representing a 6.08-fold enhancement, and the response time decreased to 11.8 ms from 19.9 ms. Furthermore, sputtering Pt nanoparticles on the surface of the MCNO film further improved the I-V characteristics in the dark, resulting in a high on/off ratio of 38.15, which is five times higher than that without the Pt nanoparticles modification. This impressive improvement in photoproperties can be attributed to the Pt nanoparticles/MCNO film barrier, plasma resonance effect generated by the Pt nanoparticles, the extinction of the Pt nanoparticles, and the reduction of surface resistance caused by the Pt nanoparticles. This highlights the potential of metal nanoparticles in the development of infrared detectors. [ABSTRACT FROM AUTHOR]