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[Display omitted] • Developing the governing principles of nanofluid impact on coal wettability. • Analyzing the mechanism of nanofluid-enhanced wettability in coal seams through hydrogen bonding and capillary forces. • Validation of macroscopic experimental results and microscopic molecular simulation results. • Demonstrating potential engineering applications of nanofluid in coal bed water injection. The technique of injecting water into coal seams is commonly used to prevent and handle mining disasters. In order to improve the effectiveness of water injection in coal seams, the impact of SiO 2 -H 2 O nanofluids on coal wettability was investigated through macroscopic physical experiments and Materials Studio software. The findings demonstrate a significant rise in the height of coal sample infiltration when using nanofluid rather than deionized water. It was found that as the particle concentration increased, the initial and dynamic contact angles of nanofluid-treated coal samples significantly decreased and the absorbed mass of coal samples in the nanofluid consistently exceeded that in deionized water. The coal sample surfaces treated with nanofluid showed a significant occurrence of nanoparticles adsorbing and aggregating. The substantial surface electrostatic potential of nanoparticles, characterized by a broad distribution of positive and negative values, facilitated hydrogen bonding with Wiser molecules and H 2 O molecules. The presence of nanoparticles on the surface of coal enhanced the adsorption of H 2 O molecules, resulting in an increase in the thickness of the interface between coal and water. There was a direct relationship observed between the number of nanoparticles and the mean square displacement of H 2 O molecules, diffusion coefficient, and the total hydrogen bonding. Consequently, nanofluids proved more advantageous than pure water in improving coal seam wettability. Through the present study, the adsorption traits of nanoparticles on the surface of coal were discovered, and the mechanism through which nanoparticles improve the wetting properties of coal seams was examined at a micro level. These findings provide a theoretical foundation for applying SiO 2 -H 2 O nanofluid to enhance coal seam wettability. [ABSTRACT FROM AUTHOR]

[Display omitted] • A novel green chemical mechanical polishing (CMP) is developed for CoCrMo alloy, including silicon sol, hydrogen peroxide, tartaric acid and deionized water. • The atomic surface obtained in this work has the lowest value of surface roughness, compared with those published on CoCrMo alloys previously. • Chelating formulas are proposed between tartaric acid and Co ions. • X-ray photoelectron and infrared spectroscopies reveal that hydrogen peroxide dominated the oxidation processes in CMP, forming oxides of Co, Cr and Mo. Cobalt-chromium-molybdenum (CoCrMo) alloy has superior wear resistance, high corrosion resistance and excellent biocompatibility. However, these properties make CoCrMo alloy become a difficult-to-machine material. Nevertheless, high-performance CoCrMo devices strictly require the surface roughness Ra less than 1 nm, arising a challenge for ultraprecision machining. To overcome the challenge, a novel green chemical mechanical polishing (CMP) is developed, including silicon oxide, hydrogen peroxide, tartaric acid and deionized water. After CMP, surface roughness Ra of 0.16 nm is achieved for CoCrMo alloy. Compared with those published on CoCrMo alloys previously, the surface roughness is the lowest. X-ray photoelectron and infrared spectroscopies reveal that hydrogen peroxide dominated the oxidation processes in CMP. Co oxides were softened and dissolved by hydrogen ions. Relatively, Cr and Mo oxides showed better stability and less dissolution in tartaric acid, avoiding excessive corrosion. The remaining oxides are removed by silicon oxide. The metal ions released are chelated by tartaric acid during the polishing process. The chelation formulas of metal ions and tartaric acid are further proposed. The developed novel green CMP provide new insights to manufacture atomic surface on an alloy with high corrosion and wear resistances, which is beneficial for the potential applications on medical devices. [ABSTRACT FROM AUTHOR]

CNF-based organic coating with different micromorphological structures was fabricated on the surface of carbon fiber (CF) by regulating the solvent ratio of binary solvents (deionized water/ethanol). The trends of their chemical components and microstructures were investigated, as well as their effects on the interfacial bonding performance of CFRP. [Display omitted] • CNF-based organic coatings with different micro-morphologies were prepared on carbon fiber surfaces by modulating the solvent ratio of binary solvents. • As the ratio of deionized water in the binary solvent increased, the CNF-based coating was gradually flattened and homogeneous, and the raised structures on the coating surfaces were gradually reduced. • The raised structures with poorer adhesion were more prone to generate stress concentration points, leading to premature fiber failure. • Crack extension in composites occurred not only in the resin phase, but also between the coating and the resin. Current research on cellulose nanofiber (CNF) in the field of mechanical properties mainly involves the direct application of CNF and simple composites with other materials. The relationship between the morphology and structure of CNF-based materials and the target functions of composites has rarely been explored. Here, as an example of carbon fiber reinforced composites (CFRP), CNF-based organic coating with different micromorphological structures was fabricated on the surface of carbon fiber (CF) by regulating the solvent ratio of binary solvents (deionized water/ethanol). The trends of their chemical components and microstructures were investigated, as well as their effects on the interfacial bonding performance of CFRP. The results indicated that an increase in the ratio of deionized water in the binary solvent led to a smaller raised structure with poor adhesion and an increase in coating uniformity on the organic coating, which would directly affect the tensile strength (TS) of the CF and the interlaminar shear strength (ILSS) of CFRP. This research presents important insights into the mechanism of composite interfaces based on the differences in the micro-morphological structures of materials. [ABSTRACT FROM AUTHOR]

[Display omitted] • The leaching effect of albite was sorted as follows: hydrochloric acid > potassium hydroxide > deionized water. • The adsorption of H 3 O+, OH− and H 2 O molecules on the surface of albite resulted in the loose framework of albite. • The H+ and K+ in solution exchanged with Na+ in albite and caused the leaching of Na element in albite. The mechanism of inorganic acid and alkali promoted weathering of albite is still unclear. In this work, the mechanism was investigated through leaching experiments and DFT simulations. The results showed that the leaching effect of albite was sorted as follows: hydrochloric acid > potassium hydroxide > deionized water. The H 3 O+ dehydrogenated by breakage of O–H bond, and then the proton bonded with the O atom to form a silicon hydroxyl group on the surface of albite. The O atom in OH− bonded with the three-coordinated Al atom to form the four-coordinated Al. The H 2 O molecule was adsorbed on the surface of albite by hydrogen bond. Meanwhile, the adsorption of H 3 O+, OH− and H 2 O on the (0 0 1) surface of albite caused the elongation of Si–O and Al–O bonds in the bulk phase, resulting in the loose framework of albite. Compared to the interaction mode of water molecules and albite, the H+ in hydrochloric acid and K+ in potassium hydroxide exchanged with Na+ in albite, which caused that the albite lattice was contracted and expanded, respectively. As a result, the surface of albite was damaged, and further caused the Na element was released from the albite crystal to liquid phase. [ABSTRACT FROM AUTHOR]

[Display omitted] • Dopamine-functionalized carbon interface enhances interfacial activity. • Boron and oxygen are codoped to optimize the capacitive behavior of carbon materials. • The inside-out pore creating method of body phase improves the activation efficiency. As a typical double-layer capacitive electrode material, carbon nanomaterials show desirable application potential in the field of capacitive deionization (CDI) and supercapacitors (SCs). In this work, interfacial functional groups and B\O co-doping defects are simultaneously introduced into multi-chamber carbon with confinement effect, and their practical applications in CDI and flexible capacitors are also studied. Specifically, the oxygen-rich carbon source and boron source, dissolved and mixed completely via co-crystallization method, released amount of gas during the pyrolysis process to produce multi-chamber honeycomb-like carbon with ultrathin walls, which were further introduced into abundant interfacial functional groups by dopamine to optimize the carbon surface. At the same time, part of boron atoms entered the carbon lattice to form boron doping at high temperature, followed by the integration with the oxygen heteroatoms in carbon source to generate abundant boron and oxygen codoping defects. The as-prepared diatomic defects by the synergistic effect promote the wettability and pseudocapacitance of the material. In addition, the derived carbon materials are endowed with good hydrophilic ability and surface activity under the modification of dopamine functional groups. The ideal hydrophilic ability ensures that the porous structure of material can be infiltrated by electrolyte to provide large effective specific surface area, which enhances the electrical double-layered capacity. The interfacial functional groups also offer additional pseudocapacitance, so as to improve the ion adsorption capacity of PDA-BOC. [ABSTRACT FROM AUTHOR]

[Display omitted] • A novel green CMP was developed for fused silica, including ceria/hexagonal boron nitride (CeO 2 /h-BN) abrasives, potassium oleate and deionized water. • During CMP, the MRR of fused silica is 31.92 μm·h−1, and surface roughness Sa is 0.124 nm after CMP. • CeO 2 /h-BN abrasives enabled realizing a new function for superlubricity during CMP, avoiding damages and achieving atomic surface. • These findings provide a new pathway to achieve atomic surface for a hard-brittle material with high MRR, using synergistic effect of abrasives. It is a challenge to produce an atomic-scale surface of fused silica with a high material removal rate (MRR) using green chemical mechanical polishing (CMP). In traditional CMP, a slurry usually contains four or more components and is normally toxic and corrosive, causing environmental degradation. To address this problem, a novel green CMP slurry for fused silica was developed using ceria/hexagonal boron nitride (CeO 2 /h-BN) abrasives, potassium oleate, and deionized water. Due to the two-dimensional nanosheet structure of h-BN, it is simple to generate a sheared layer, which lowers friction at the contact area. Ceria abrasives realized a new function for superlubricity during CMP through this design, preventing damages and reaching atomic-scale surface. This is confirmed by research showing that a damaged layer's thickness following CMP, as determined by high-resolution transmission electron microscopy, is only 2.7 nm. The MRR of fused silica is 31.92 µm•h−1 during CMP, and surface roughness Sa is 0.124 nm after CMP. The MRR is currently at its highest with such a low surface roughness. These findings provide a new pathway to achieve an atomic-scale surface for a hard-brittle material with a high MRR using the synergistic effect of abrasives. [ABSTRACT FROM AUTHOR]

[Display omitted] • E-waste can be strategically converted into energy-storing electrodes. • Interesting core–shell morphology is formed by a facile two-step synthesis process. • The optimized NiSe-120/Cu 4 O x -3 electrode shows an areal capacity of 138.27 µAh cm−2. • Excellent stability is achieved even after 50,000 charge–discharge cycles. • The C-type HSC device exhibits a good areal capacitance of 233.1 mF cm−2. Recently, for energy storage materials, various surfactant-less synthesis methods have been attaining extensive attention from researchers. Herein, we utilized the wasted desoldering copper wicks (E-waste) as the base substrate to synthesize hierarchical core–shell maze-corn-like nickel selenide/copper oxide (NiSe/Cu 4 O x) architectures by a facile two-step synthesis process. Initially, the Cu 4 O x nanorods (NRs) were grown directly over the surface of the flat braided E-waste copper wicks by thermal oxidation, followed by a facile electrodeposition method to coat the pre-existing Cu 4 O x NRs with NiSe nanoparticles. The optimized NiSe-120/Cu 4 O x -3 electrode exhibited superior electrochemical characteristics (138.27 µAh cm−2 at 4 mA cm−2) compared to the other electrodes, owing to the contribution of core and shell materials, and sustained an ultra-long cycling test of 50,000 charge/discharge cycles with an excellent capacity retention of 98.7%. Inspired by commercially available AA battery, the as-synthesized working electrode was coupled with activated carbon-coated nickel foam to fabricate a cylindrical-type (C-type) hybrid supercapacitor (HSC) device, with an areal capacitance of 233.1 mF cm−2 accompanied by an extraordinary cycling efficiency of 99.1%. Furthermore, the C-type HSC device exhibited maximum energy and power densities of 70.9 µWh cm−2 and 14,000 µW cm−2, respectively and it was tested by powering portable electronics for real-time application. [ABSTRACT FROM AUTHOR]

[Display omitted] • A novel method for diamond surface hydroxylation was developed. • The OH-diamond shows high intensity of C O bonds and untraceable C O bonds. • O H and C O stretching vibration was observed in the FTIR spectra. • APTES was successfully functionalized on the OH-diamond surface. • The stability of OH-diamond was investigated by ReaxFF and DFT calculations. Functionalized diamond is promising for biosensing applications due to its attractive properties. Hydroxyl terminated diamond (OH-diamond) surface with chemically functionalizable carboxyl groups is beneficial to silanization, which creating an amine termination is necessary to immobilize proteins and DNA. However, fabrication of high quality OH-diamond surface is still difficult. In this work, OH-diamond is obtained by hydroxide ion treatments in deionized water at high voltages up to 3000 V. The OH-diamond exhibited high intensity of singly oxidized C Ⅰ carbon bonds (C OH and C O C) and untraceable doubly oxidized C Ⅱ carbon bonds (C O or O C O), characterized by X-ray photoelectron spectroscopy measurements. Meanwhile, O H and C O stretching vibration was observed in the Fourier transform infrared spectra. Furthermore, silanizaiton is achieved by 3-aminopropyltriethoxysilane (APTES) on the OH-diamond surface via condensation reaction with surface C OH groups. In the end, the stability of OH-diamond surface was investigated by ReaxFF simulations and density function theory (DFT) calculations. [ABSTRACT FROM AUTHOR]

[Display omitted] • Dual pseudocapacitive electrode/redox electrolyte systems. • Enlarged potential window and cell voltage. • High energy- and power-densities of supercabattery devices. Supercabatteries refer to those supercapacitors with supercapacitor-like high power density and battery-like high energy density. In this work, dual pseudocapacitive electrode/redox electrolyte systems, namely MnO 2 @carbon cloth/Na 2 SO 4 + KI and Fe 2 O 3 @carbon cloth/Na 2 SO 4 + ethyl viologen dibromide, have been designed and developed. As the cathodic and anodic systems, they are employed for the construction of asymmetric supercabatteries. The different working potential windows of two systems lead to a cell voltage of as high as 2.0 V. The synergistic effect of two redox species on the electrode and in the electrolyte results in an enlarged capacitance of 509.1 mF cm−2 at a current density of 10 mA cm−2. The supercabattery device delivers a maximal energy of 6.6 Wh L−1 and a maximal power density of 357.6 W L−1. They are higher than those of most of reported manganese oxide//iron oxide based asymmetric supercapacitor devices, and meanwhile comparable to those of some rechargeable batteries. The integration of pseudocapacitive electrodes with redox electrolytes is thus an efficient approach to construct energy storage devices such as supercapacitors with both high power- and energy-densities. [ABSTRACT FROM AUTHOR]

[Display omitted] • Pulse laser ablated highly crystalline Ag and Cu nanoparticles were produced in deionized water. • Structure, morphology and optical properties of NPs were strongly affected by changing laser fluencies. • Overall characteristics of these NPs were shown to be tailored by laser fluence tuning. • Optical band gap energies of nanoparticles were increased with the increase of laser fluence. • Obtained nanoparticles may be useful for photovoltaic and photocatalytic applications. Production of high purity silver (Ag) and copper (Cu) nanoparticles (NPs) with desired physical properties remains challenging. Thus, pulsed laser ablation in liquid (PLAL) method was used to prepare spherical AgNPs and CuNPs in deionized water (DIW) at various laser fluencies (LFs) (2.83–14.15 J cm−2). The structures, morphologies and optical behavior of these NPs as a function of varying LFs were determined. UV–Vis absorbance of these NPs was gradually increased accompanied by a blue shift. The optical band gap energy of AgNPs and CuNPs were in the range of 2.66–2.79 eV and 3.14–3.44 eV, respectively, wherein ATR-IR spectra confirmed their high purity. TEM and HRTEM images displayed the nucleation of spherical, homogenous, and crystalline AgNPs and CuNPs with corresponding mean diameter ranged from 8.1 to 32.5 nm and 6.2–33.1 nm. It is asserted that the obtained pure and spherical AgNPs and CuNPs with customized properties may be beneficial for photovoltaic and photocatalytic applications. [ABSTRACT FROM AUTHOR]

This study utilizes light adsorbing molecule, phenothiazine (PTZ) to reduce graphene oxide (GO) and functionalize into PTZ-rGO aerogel (PTZ-rGO). The UV excited PTZ reduces GO via electron transfer while PTZ is simultaneously oxidized and functionalized onto rGO to produce PTZ-rGO aerogel. The optimum incorporation of PTZ on rGO sheets renders good electrochemical active surface area of 495.71 m2 g−1 and enhances the diffusion behavior up to 41.92%. This pseudocapacitive effect and the excellent surface property provide promising charge storage results of 235.5 F g−1 at 0.5 A g−1. Furthermore, the stable charge-discharge cycles with 92% capacitance retention after 10,000 cycles render it an excellent electrode material for supercapacitor fabrication. [Display omitted] • One-step approach to produce functionalized rGO aerogel by UV excitation. • UV excites phenothiazine to transfer electron to GO for its reduction. • Functionalized phenothiazine produces pseudocapacitive effect. • Phenothiazine functionalized rGO aerogel can be supercapacitor electrode. [ABSTRACT FROM AUTHOR]

[Display omitted] • Lanthanum hydroxide was firmly loaded on N -doped C layer modified ACF without binder. • LNA exhibited stable P electrosorption behavior after 5 adsorption–desorption cycles. • The Langmuir maximum electrosorption capacity of P on LNA was 70.656 mg/g. • Co-existing anions improved P removal in the order of Cl->NO 3 –>SO 4 2-> HCO 3 –>CO 3 2– • N -doped C layer promoted P electrosorption by affecting electronic structure of La. Binder-free La(OH) 3 supported activated carbon fiber (ACF) electrode with modification of N -doped C layer (named LNA) was developed for phosphate (P) electrosorption. The optimum electrosorption of P on LNA was achieved at pH = 4 and voltage = 4 V. The electrosorption capacity was 6.5 times that without voltage, and adsorption rate also increased by 9 times. The presence of 0.1 mol/L inorganic anions improved the electrosorption efficiency in the order of Cl->NO 3 –>SO 4 2->HCO 3 –>CO 3 2–. The regeneration study revealed that LNA still exhibited a high electrosorption capacity (29.91 mg/g) after 5 cycles. The mechanism of phosphate electrosorption of LNA was analyzed by kinetics, isotherms, FTIR and XPS, etc. The adsorption kinetics followed the pseudo-second-order model, and the adsorption equilibrium data were well described by the Langmuir isotherm. The Langmuir maximum electrosorption capacity of LNA was 70.66 mg/g. The electrosorption of phosphate was controlled by ion exchange, electrostatic attraction and the formation of surface complexes. N -doped C layer affected the local electronic structure of La and strengthened the interaction with lanthanum hydroxide, promoting the electrosorption of phosphate. The results demonstrated that LNA is a promising electrosorption material for efficient phosphate recovery. [ABSTRACT FROM AUTHOR]

[Display omitted] • A simple and non-destructive three-electrode EIS method was established for ACF. • Equivalent circuits and one-dimensional EDLC electrodes were constructed. • Weaving patterns of ACF affect their electrochemical performance. • Volumetric adsorption capacity (VAC) and capacitance (VSC) are positively related. • Knitted ACFs show lower energy consumption than woven ACFs. Activated carbon fibres (ACFs) are successful electrode materials for capacitive deionization (CDI) owing to their excellent electrochemical properties and commercial availability, for example, with knitted or woven morphology patterns. However, the lack of a common and effective analytical framework to analyse the performance of ACFs is hindering further progress in the area. This study establishes an electrochemical impedance-based method to detect and investigate the electrochemical properties of ACF materials without destroying their original weaving patterns. Five commercial ACFs with two distinct patterns and similar specific surface areas were investigated. Data from electrochemical impedance spectroscopy (EIS) are compared to the desalination performance and energy consumption of the ACFs in a CDI cell. The weaving pattern played a role in the electrochemical properties and desalination performance. The volume-salt adsorption capacities in CDI were related to the volume-specific capacities in EIS, however, there was no significant difference between knitted and woven materials. Linked to EIS features, knitted ACFs consume less energy than woven ACFs for removing the same amount of NaCl from water. These results provide ACF researchers with a new, effective, and readily available approach for measuring the electrochemical performance of ACF materials via EIS. [ABSTRACT FROM AUTHOR]

[Display omitted] • Superhydrophobic antireflective film was prepared by a low-cost dip-coating and simple solution immersion method. • An environmentally friendly non-fluorinated surface modifier contributed to the enhancement of superhydrophobicity and transparency. • The films demonstrated good superhydrophobicity, high visible transmittance of 95.31% and outstanding durability towards UVA irradiation and acidic corrosion and deionized water immersion. • The superhydrophobic surfaces could also be produced by spraying method. Nowadays, there are several ways to prepare transparent superhydrophobic films for photovoltaic glass covers, but majority involve fluorosilane modifications, which are not only environmentally unfriendly but also can be hazardous to individuals. In this research, a non-fluorinated dip-coating method was proposed to prepare the film with a superhydrophobic layer and an antireflective layer. The antireflective layer with a network of nanopore-like structures was formed through a pore-forming agent. Then the superhydrophobic layer was deposited on above layer by simple immersion. Superhydrophobic silica nanoparticles would adhere to those structures, thus reducing the nanopore size and roughness, and increasing the transmittance. Finally, to enhance the films' self-cleaning abilities, a non-fluorinated silane modifier Hexamethyldisilazane (HMDS) was adopted. The film presented the average transmittance of 93.66 % in the wavelength range of 300 ∼ 1200 nm. The average static water contact angle (WCA) was 152°. In the self-cleaning test no dust was retained on the surface. The UV resistance test revealed that the film possessed outstanding UVA resistance. Moreover, the superhydrophobic films maintained transmittance stability against acidic (pH = 2) and deionized water (pH = 7) immersion. This environment friendly and low-cost preparation creates possibilities in photovoltaic glass covers and other fields. [ABSTRACT FROM AUTHOR]

[Display omitted] • We report the synthesis and study of porous carbon derived from ZIF-67 for electrosorption study of NaCl. • The electrochemical analysis confirms the significant increase in the specific capacitance of PC-ZIF-67. • PC-ZIF-67 exhibits high electrosorption capacity of 28.13 mg/g. • The values of SAC fit well with Freundlich adsorption isotherm. Capacitive deionization (CDI) is an emerging and environmentally friendly technology for water desalination with promising future. The electrode material with high electrosorption performance is critical in CDI application. Here, we report the synthesis and study of porous carbon derived from zeolitic imidazolate framework-67 (ZIF-67) for electrosorption study of NaCl. The morphology and graphitic degree are analysed by X-ray diffraction and scanning electron microscope. The electrochemical analysis is performed using cyclic voltammetry and galvanostatic charge-discharge confirming the significant increase in the specific capacitance of porous carbon derived from ZIF-67. Further, the porous carbon derived from ZIF-67 was studied for deionization of water and exhibits high electrosorption capacity of 28.13 mg/g for initial salt concentration of 800 mg/L at 1.4 V. [ABSTRACT FROM AUTHOR]

[Display omitted] • Ferroelectricity is significantly affected by post cooling rate. • Rapid quenching enhances remnant polarization of Al-doped HfO 2 thin film. • Stable reliability is obtained using quenched Al-doped HfO 2 device. A study was conducted on how the cooling rate after the phase change heat treatment required to secure the ferroelectric (FE) properties affects the ferroelectricity of Al-doped HfO 2 (Al:HfO 2) thin films. When cooling the thin film to room temperature after heat treatment, the cooling rate was controlled through slow chamber cooling, which maintains and cools the sample inside the heat treatment equipment, slightly faster air cooling, and rapid cooling using deionized water. We achieved the dramatic increase of remnant polarization (P r) and coercive electric field (E c) using rapid quenching after phase change heat treatment. The 2P r and 2E c values of rapid quenched FE Al:HfO 2 thin film are approximately ∼100 μC/cm2 and ∼9.5 MV/cm, respectively, which are the highest records among HfO 2 -based FE thin films reported so far. These significant improvements are attributed to inducing homogeneously distributed defects complexes and higher stress/confinement strain within Al:HfO 2 thin film, leading to preventing pinched hysteresis loop and stabilize orthorhombic crystal structure. Furthermore, endurance up to 2 × 106 cycles and reasonable projected 10 years retention properties were achieved, stably without wake-up and fatigue in quenched FE Al:HfO 2 capacitor. These results propose a beneficial method to improve the ferroelectricity of HfO 2 -based thin films. [ABSTRACT FROM AUTHOR]

[Display omitted] • The Bi 2 S 3 /Bi 2 O 2 CO 3 /Bi 3 O 4 Cl heterojunction is constructed through the in-situ hydrothermal method. • The heterostructure effectively promotes the separation of the photogenerated electron-hole pairs. • Bi 2 S 3 /Bi 2 O 2 CO 3 /Bi 3 O 4 Cl exhibits better photocatalytic performance than pure Bi3O 4 Cl. In this work, a Bi 2 S 3 /Bi 2 O 2 CO 3 /Bi 3 O 4 Cl ternary heterojunction was constructed in situ using a one-step hydrothermal method for the photocatalytic degradation of ciprofloxacin (CIP) and rhodamine B (RhB). For the Bi 2 S 3 /Bi 2 O 2 CO 3 /Bi 3 O 4 Cl ternary heterojunction, Bi 3 O 4 Cl provided the bismuth source to generate tightly bonded heterojunctions in situ. Bi 2 O 2 CO 3 formed from the thiourea and CO 2 in air was used as a trap for the photogenerated electrons of Bi 3 O 4 Cl and Bi 2 S 3. The Bi 2 S 3 from thiourea improved the optical properties of the catalyst. Compared with pure Bi 3 O 4 Cl, Bi 2 S 3 /Bi 2 O 2 CO 3 /Bi 3 O 4 Cl (BBS-0.2) which was prepared by adding 0.2 mol thiourea and 0.3 g Bi 3 O 4 Cl to 60 mL deionized water, showed a better photocatalytic performance. The degradation efficiencies of 87.2% CIP in 80 min and 64.8% RhB in 180 min under light irradiation, are 2.4 times and 2.0 times of Bi 3 O 4 Cl, respectively. The feasible preparation of Bi 2 S 3 /Bi 2 O 2 CO 3 /Bi 3 O 4 Cl could provide as applicable reference for the development Bi-ternary heterojunction with high photocatalytic performance. [ABSTRACT FROM AUTHOR]

Uniform graphitic-carbon nitride quantum dots were fabricated through a combination of hydrothermal treatment, sintering and sonication methods and the production yield is up to 39 %. The obtained graphitic-carbon nitride quantum dots dry powder possesses outstanding redispersibility, stability and water solubility in deionized water. [Display omitted] • Mass production of g-C 3 N 4 quantum dots was achieved through an efficient method. • The production yield of g-C 3 N 4 quantum dots is up to 39 %. • The g-C 3 N 4 quantum dots have excellent redispersibility and stability and in deionized water. • The g-C 3 N 4 quantum dots exhibited high sensitivity and selectivity to Fe3+. • The g-C 3 N 4 quantum dots were subjected to the photocatalytic degradation of rhodamine B and methyl orange. Graphitic-carbon nitride quantum dots (gCNQDs) have various fascinating properties and potential applications, but the low yield production of gCNQDs by current synthetic methods severely limits to exploit their properties and large-scale applications. Here we report the large scale synthesis of uniform gCNQDs through a combination of hydrothermal treatment, sintering and sonication methods for the first time. The production yield is up to 39 %, and the obtained gCNQDs dry powder possesses outstanding redispersibility, stability and water solubility in deionized water. The gCNQDs aqueous suspensions emit bright blue luminescence under UV excitation and can be an effective fluorescence probe for Fe3+ detection with good selectivity, sensitivity and photostability. The fluorescent probe shows low cytotoxicity and good cell-permeability, and then being successfully applied for the fluorescence imaging of Fe3+ in living cells. Moreover, the gCNQDs show the improved photocatalytic activity, which was evaluated by degradation of Rhodamine B and Methyl Orange. The large scale synthesis of gCNQDs with outstanding fluorescent properties, biocompatibility and photocatalytic properties can effectively facilitate the applications of gCNQDs and gCNQDs based nanocomposites in various fields. [ABSTRACT FROM AUTHOR]

[Display omitted] • Highly efficient nanocomposites were obtained solvothermally. • 5-fluorouracil was oxidized major by h+ and minor by O 2 – • The roles of B:DGNW in enhancing photocatalytic activity were complex. • Cytostatic drug was effectively photooxidized in actual fresh and sea waters. • (BiO) 2 OHCl/BiOBr-1.5%B:DGNW is a promising material for water purification. In this work, a series of novel (BiO) 2 OHCl/BiOBr-x%B:DGNW (x = 0%, 1%, 1.5%, 2%) composites with different content of boron-doped diamond/graphene nanowalls (B:DGNW) were fabricated by simple solvothermal synthesis. A boron-doped diamond/graphene nanowalls (B:DGNW) were prepared by CVD method. A series of analyses: XRD, XPS, SEM, and TEM showed that the photocatalyst (BiO) 2 OHCl/BiOBr-x%B:DGNW with a "flower-like" morphology was successfully synthesized. The photocatalytic activity of the obtained composites in the degradation of 5-fluorouracil (5-FU) in various water matrices (deionized water, sea, and surface water) under the influence of artificial solar radiation was assessed. The results showed that all the prepared (BiO) 2 OHCl/BiOBr-x%B:DGNW composites were characterized by excellent photocatalytic activity. The calculated pseudo-first rate constant for 5-FU degradation increased with the elevation of amount of B:DGNW up to 1.5% in (BiO) 2 OHCl/BiOBr, and it dropped down to value obtained for non-riched material by B:DGNW, when of 2% B:DGNW was introduced to composite. The results showed that B:DGNW play a key role in the separation of charge carriers h+/e- enhancing degradation rate of 5-FU. The photoactivity of (BiO) 2 OHCl/BiOBr-1.5%B:DGNW composite to 5-FU removal was also satisfied in natural water, although its structure has changed in seawater. [ABSTRACT FROM AUTHOR]

[Display omitted] • Carbon fiber is treated by NH 3 plasma with low damage to realize electrostatic self-assembly with graphene oxide. • Graphene oxide of different sizes forms multi-layered restoration structures on fiber surfaces by electrostatic forces. • Electrostatic self-assemblies of carbon fibers with graphene oxide can optimize the mechanical properties of composites. The introduction of graphene oxide (GO) on the surface of carbon fiber (CF) is considered an effective strategy to modulate the structure and properties of the fiber/matrix interface in CF reinforced polymer composites. However, the tensile strength of fibers often decreases due to the etching effect during treatment. In this study, a new method was proposed to graft GO onto fiber surfaces by electrostatic self-assembly. The results showed that NH 2 grafted onto CF through NH 3 plasma treatment caused CF and GO to have opposite charges in deionized water; subsequently, they self-assembled to form CF@GO due to the electrostatic force. The tensile strength of CF@GO was 31.23% greater than that of pristine CF, which may be because the different sizes of GO repaired the surface defects on the CF with its multilayer restoration structure. The CF showed a noticeable improvement in surface wettability due to the GO coating. Moreover, the interfacial properties were significantly improved, with the interfacial shear strength (IFSS) of CF@GO increasing to 81.31 MPa, which was about twice that of unmodified CF. This work provides a promising strategy for nondestructive grafting nanoparticles on CF to build a strong interface in CF composites. [ABSTRACT FROM AUTHOR]

Novel double perovskite La 2 AlFeO 6 prepared by glucose complexing agent through sol–gel method shows satisfactory surface area, photocatalytic performance for phenol degradation and magnetism. [Display omitted] • La 2 AlFeO 6 with high surface area were prepared by glucose with sol–gel method. • The magnetism can be improved by using glucose complex agent. • La 2 AlFeO 6 prepared by glucose shows superior photocatalytic activity. • Double perovskite La 2 AlFeO 6 was first time prepared for phenol degradation. Photo-Fenton process is an efficient way to treat the organic pollutants in wastewater. However, the efficiency is limited by serious leaching of iron ions, separation of spent catalyst from reaction system for facile recycling, acidic reaction environment (pH＜4). Herein, a novel double perovskite photocatalyst La 2 AlFeO 6 with high surface area was developed to counter these issues. By altering complexing agents, iron ion content discrepancy and B'-O-B" varies in La 2 AlFeO 6 led to a high surface Fe3+ ratio and an excellent magnetic property. >98.4% of phenol could be degraded in a wide pH range over La 2 AlFeO 6 because of the high surface Fe3+ ratio and promotion of generated ·OH, ·O 2 – and 1O 2. The excellent magnetic property would contribute to separate catalyst from water, and led the used La 2 AlFeO 6 to be reused after simple deionized water rinsing and air drying without any further treatment or calcination. [ABSTRACT FROM AUTHOR]

[Display omitted] • Photocatalytic seawater splitting for hydrogen is studied by simulated sunlight. • Heterojunction Pt/GaP-C 3 N 4 photocatalyst was synthesized by ionothermal method. • Apparent quantum yield of artificial seawater is near 2 times higher than that of pure water. • Mechanism of photocatalytic seawater splitting is presented compared with pure water. Solar-driven photocatalytic seawater splitting for hydrogen is a promising process because of unlimited solar energy and seawater available. A novel Pt/GaP-C 3 N 4 (PGC) heterogeneous photocatalyst was fabricated and used for photocatalytic artificial and natural seawater splitting under simulated sunlight illumination. The hybrid heterojunction structure of GaP-C 3 N 4 promotes a Z-schematic electron migration and depresses the recombination rate of photogenerated electron-hole pairs in PGC photocatalyst. Under 4-hour simulated sunlight irradiation, the optimum composite 0.3PGC50 (0.3 wt% Pt-loaded and 50 wt% GaP-composited) exhibited high photoactivity performance with the hydrogen/oxygen evolution rate (HER/OER) of 46.5/23.4 µmol g−1 in deionized water, 65.5/34.3 µmol g−1 in the artificial seawater, and 53.9/24.9 µmol g−1 in the natural seawater splitting process. The apparent quantum yield of artificial seawater is near two times higher than that of pure water. The molar ratio of H 2 :O 2 was near 2:1 matched whole water splitting, and the H 2 yields were moderately decreased after 3 consecutive runs. [ABSTRACT FROM AUTHOR]

[Display omitted] • Nitrogen plasma can fabricate disorder layers (3 ∼ 5 nm) on the surface of α-MnO 2. • Abundant oxygen vacancies appeared in the disorder layers of α-MnO 2. • Oxygen vacancies improved the capacitive performance of α-MnO 2 even at high mass loading (12 mg cm−2). The electrochemical performance of high theoretical capacitance MnO 2 is usually restricted to low mass loading electrode due to the slower electron/ion diffusion kinetics in dense electrodes. Defect engineering has been supposed to an effective way to improve the capacitive performance of transition metal oxides. Herein, cactus-like structure MnO 2 was grown on carbon cloth (CC) and treated with N 2 -plasma to obtain the N-MnO 2 electrode with high mass loading of 12 mg cm−2. Benefiting from the hierarchical structure and rich oxygen vacancies, the as-prepared N-MnO 2 electrode delivered a high mass specific capacitance of 443F g−1 and a high areal capacitance of 5320 mF cm−2. Furthermore, the N-MnO 2 electrode released an excellent rate capability with 71.8% capacitance retention at 20 mA cm−2 as well as gratifying cycling life with 96 % capacitance retention after 8 000 cycles at 20 mA cm−2. Moreover, an asymmetrical supercapacitor device assembled by N-MnO 2 and activated CC can achieve a high energy density of 0.56 mWh cm−2 (46 Wh kg−1) at the power density of 5.14 mW cm−2 (420 W kg−1) with good cycle stability. Such facile N 2 -plasma treatment for defect engineering shows great potential in the rational design for advanced supercapacitor electrodes with high mass loading. [ABSTRACT FROM AUTHOR]

[Display omitted] • TiO 2 and Ag-TiO 2 nanoparticles (NPs) synthesized in deionized water using femtosecond laser ablation/irradiation techniques. • Broadband femtosecond Z-scan experiments performed with kHz and MHz pulses. • 2PA coefficients of ~10-8 cm/W and 3PA coefficients of ~10-15 cm3/W2 were retrieved with MHz excitation. • The presence of a prominent 3PA (~10-23 cm3/W2) using kHz excitation was established. • A correlation has been established with thermal-optic influence with MHz pulses. • Plasmon-enhanced nonlinear absorption in the case of 1 kHz pulses recognized. We report the results obtained from our extensive femtosecond (fs) nonlinear optical (NLO) studies of titanium dioxide (TiO 2) and silver (Ag) doped titanium dioxide (Ag-TiO 2) nanoparticles. TiO 2 as well as Ag-TiO 2 nanoparticles (NPs) were synthesized in deionized water using the techniques of fs laser ablation and simultaneous laser induced chemical reduction through irradiation, respectively. The broadband third-order nonlinear optical (NLO) behaviour of the synthesized NPs was investigated by employing the standard open and closed aperture Z-scan experiments with fs laser pulses delivered from an oscillator (~80 MHz repetition rate at wavelengths of 700 nm, 750 nm, 800 nm, 850 nm) and amplifier pulses (1 kHz repetition rate at wavelengths of 800 nm, 1000 nm, 1100 nm, 1200 nm). The corresponding NLO coefficients [two-photon absorption (2PA) coefficients of ~10-8 cm/W and three-photon absorption (3PA) coefficients of ~10-15 cm3/W2 with MHz excitation] were retrieved from the theoretical fits to the experimental Z-scan data. It was evident from the experimental observations that the Ag-TiO 2 NPs demonstrated a significant tendency towards 3PA and also crucially higher nonlinear susceptibility [χ(3)] in comparison with the pure TiO 2 NPs. In this extensive investigation, not only a remarkable correlation has been established regarding the incorporation of Ag into TiO 2 matrix with thermal-optic influence (MHz interaction) but also the fundamental plasmon-enhanced nonlinear absorption (NLA) in the case of 1 kHz pulse excitation has been decisively recognized. The synthesized nanocomposites were scrupulously probed in the near-IR regime, unveiling the presence of a prominent 3PA (with retrieved coefficients of ~10-23 cm3/W2 using kHz excitation), an essentially rare observation in these kinds of NPs. [ABSTRACT FROM AUTHOR]

[Display omitted] • NiO x nanoparticles were produced by laser ablation in deionized water and air. • Live/dead tests revealed structural damage to the bacterial membranes. • FTIR spectroscopy exhibit enhancement of IR-absorption in molecular fragments. Food pathogens (Staphylococcus aureus , Listeria monocytogenes , and Pseudomonas aeruginosa) in planktonic form were subjected to bactericidal treatment by colloidal nanoparticles. NiO x colloidal nanoparticles, as anti-biotic nanomaterial, were produced by laser ablation in deionized water and air, and comprehensively characterized by x-ray diffraction, scanning electron microscopy, energy dispersive X-ray, Raman, Fourier transformed infrared (FT-IR) spectroscopy, dynamic light scattering size and zeta-potential measurements. Normalized Fourier transformed infrared (FT-IR) spectra of the nanoparticle-inactivated bacteria deposits exhibit for the larger, positively charged water-borne nanoparticles pronounced enhancement of IR-absorption in molecular fragments, comprising the bacterial membrane, which appears to be unfavorable for the inactivation of the food bacteria strains. In contrast, smaller and less charged air-borne nanoparticles exhibit less influence in IR-absorption, but pronounced TEM-envisioned penetration inside these pathogenic bacteria, resulting, according to the complementary microbiological tests, in their efficient inactivation. The study will help to understand the possible mechanisms responsible for the death of bacteria at their interacting with antibacterial nanoparticles. [ABSTRACT FROM AUTHOR]

• Amorphous WO 3 intermediate layer was used to protect the graphene surface. • The WO 3 was dissolved in a deionized water, and no damage occurred to graphene surface. • The performance enhancement was quantitatively verified via the photodetector. • The surface-protected photodetector recorded a 1.74 times higher photoresponsivity and 4s faster temporal photo response time. After the successful synthesis of graphene using chemical vapor deposition in 2009, the large-area/defect-free transfer method still remains a critical issue for implementing high-performance graphene-based electronic devices. Here, for the first time, we demonstrated a specially prepared water-soluble amorphous WO 3 intermediate layer to effectively protect the graphene surface from immediately after its synthesis to transfer and final unit processing. Moreover, using the photodetector to which the proposed protection method was applied, the performance improvement was quantitatively verified. Compared with the control device, the surface-protected photodetector recorded a higher photoresponsivity of 1.74 times and faster temporal photoswitching response time of 4 s or more. The graphene surface protection method using the WO 3 intermediate layer allows the reversibility in transfer process and performance enhancement of graphene-based electronic devices. [ABSTRACT FROM AUTHOR]

[Display omitted] • Sr-rich phases onto SrVO 3 thin films are studied using Angle Resolved XPS. • A treatment in water removes Sr excess by giving a V-OH terminated surface. • A study of air-ageing onto "as-grown" and "H 2 O-treated" SVO is finally pursued. In this work, 40 nm-thick films of SrVO 3 (SVO) grown by Pulsed Laser Deposition (PLD) on SrTiO 3 substrates are studied by X-Ray Photoelectron Spectroscopy (XPS). We develop here a systematic fitting procedure for both Sr3d, V2p 3/2 and O1s spectral regions of interest associated to the different chemical environments. Joint angle resolved XPS and Ar ion depth profiling reveal that as-grown SVO thin films exhibits Sr-rich phases at the extreme surface and a near-stoichiometric SVO in the bulk. The removal of segregated Sr is proposed by a treatment in deionized ultrapure water. This step will become an essential technological step in order to obtain reproducible surfaces achieving a stoichiometric SVO oxide phase. Besides, these hydrolyzed SVO surfaces appears VO 2 terminated and then more electrically active. Furthermore, an air-ageing comparative study between as-grown and H 2 O-treated samples reveals that hydrolyzed surfaces are more surface sensitive to air oxidation. Such observations will be crucial and must be carefully considered before performing any passivation process for the integration of SVO thin film into next generation electronics heterostructures. [ABSTRACT FROM AUTHOR]

[Display omitted] • Flexible sandwich Ni(OH) 2 /NP-Ni/MG electrodes are synthesized by two-step methods. • Glucose sensor property of electrode is almost unchanged under severe bending. • The electrode possesses highly electrocatalytic activity and long-term stability. In this work, flexible sandwich β-Ni(OH) 2 nanopetals/nanoporous Ni/metallic glass (β-Ni(OH) 2 /NP-Ni/MG) electrodes for non-enzyme glucose sensor are fabricated by a facile two-step route, including dealloying Ni 40 Zr 20 Ti 40 MG in HF solution and subsequently immersing the dealloyed sample in deionized water. The binder-free β-Ni(OH) 2 /NP-Ni/MG electrodes exhibit an excellent flexibility arising from the MG interlayer, which can be directly applied for glucose sensor without complex modification and assembly. The morphology, surface chemical states, and sensing performance of flexible electrodes are examined. The interwoven β-Ni(OH) 2 nanopetals in-situ grown on the NP-Ni network provide large surface areas and affluent catalytic active sites, which accelerates the glucose diffusion and improves the utilization rate of active substances. Using the β-Ni(OH) 2 /NP-Ni/MG electrodes as non-enzymatic glucose sensor, a high sensitivity of 1.496 mA mM−1 cm−2 and a wide linear detection range up to 18 mM are achieved. Meanwhile, the present sandwich electrode shows high anti-interference ability, enhanced reproducibility, and long-term stability. The potential application of flexible β-Ni(OH) 2 /NP-Ni/MG electrodes as wearable electrode materials is discussed in detail. Moreover, the growth mechanism of β-Ni(OH) 2 nanopetals is proposed. In summary, the β-Ni(OH) 2 /NP-Ni/MG electrode has a promising application prospect in wearable glucose sensor. [ABSTRACT FROM AUTHOR]