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Methyl orange (MO), which is known as a highly durable dye that is extremely toxic to humans and animals, has been processed by using various methods. In recent years, MO degradation through reduction in the presence of NaBH 4 (NB) and suitable nanocatalyst have garnered considerable interest. However, the nanosized particles of the catalyst make separation from the liquid solution more difficult and limit the practical application of this technique. Herein, copper nanoparticles (CuNPs) decorated on three-dimensional chitosan aerogel (CSA) were synthesized as a reusable composite for the catalytic degradation of MO by using a green method with durian (Durio zibethinus) shell (DS) extract as a reducing agent. The Cu/CSA composite's physicochemical properties were characterized by using X-ray Diffraction (XRD), Fourier-transform infrared spectroscopy (FT-IR), Scanning electron microscopy- energy dispersive X-ray spectroscopy (SEM-EDS), high resolution Transmission electron microscopy (HR-TEM), Brunauer-Emmett-Teller (BET) and Raman spectroscopy. These modern techniques elucidated the structure and formation of copper nanoparticles on the CSA surface. The copper nanocatalysts have an average particle size of 32.6 nm, specific surface area of 55.8 m2/g, pore size of 32 Å and pore area of 0.049 cm3/g. Through the investigation of catalyst activity, the conditions of MO reduction were optimised with the 1.0 Cu/CSA sample, catalyst dose of 0.5 g/L and a molar ratio of MO/NB of 1/200. The reaction reached over 94.3% efficiency after 10 min, correlating with a kinetic rate constant of 0.163 min−1. It is worth mentioning that the optimized catalyst can be conveniently synthesized and retrieved from the reaction solution in just 5 s using a vacuum filter. Furthermore, its effectiveness remains largely unaffected even after undergoing five cycles of reuse, thus demonstrating its exceptional durability and potential in environmental remediation. [Display omitted] • An alternative chitosan aerogel-based support for metal nanoparticles. • Nano-copper/chitosan aerogel (Cu/CSA): a benign reduction using durian shell extract. • Outstanding reactivity of Cu/CSA in the catalytic reduction of methyl orange. • High stability and proficient reusability of Cu/CSA during 5 consecutive cycles. [ABSTRACT FROM AUTHOR]

Atomic and close-to-atomic scale manufacturing is a new technology that can achieve atomic-level manufacturing precision and functional critical dimension. Here we propose an efficient approach for atomic-scale chemical mechanical polishing (CMP) surface of fine copper utilizing optimized CMP slurry and polishing parameters. The optimal polishing slurry is composed of silica, hydrogen peroxide, aspartic acid, sodium phosphate and deionized water, where abrasive particles of silica nanospheres synthesized are uniformly dispersed. Prior to CMP, copper was precisely lapped by ceria slurry. After CMP, the surface roughness is 0.099 nm with an area of 50 × 50 µm2. Atomic-level flatness surface is acquired. To the best of our knowledge, it is the lowest surface roughness with such a relatively large scanning area, compared with those published previously. High resolution transmission electron microscopy (HRTEM) images of polishing surface further prove that atomic-scale surface roughness is achieved. X-ray photoelectron spectra clarify CMP mechanism that complex oxidation, ionization and chelation are sparked on copper surface and the soft layer is formed. The presented efficient approach for atomic-scale polishing will widen the application fields of copper materials and copper-based components. [Display omitted] [ABSTRACT FROM AUTHOR]

Tin material corrosion has been recognized as an important problem for electronic products. Biomimetics strategies have been adopted to develop intriguing materials to combat corrosion. In this paper, by anodic oxidation, mussel inspired dopamine hydrochloride modification and thiol grafting, lotus leaf inspired superhydrophobic surface (SHS) based on porous SnO 2 coating is prepared on tin. Further, a stable liquid infused surface (LIS) enlightened by Nepenthes plant is formed by infusing dimethyl silicone oil into SHS. The wettability, microstructure and chemical composition of tin surface with different modification are characterized by contact angle, scanning electron microscopy (SEM), high resolution transmission electron microscopy (HRTEM), X-ray photoelectron spectroscopy (XPS) and so forth. The porous SnO 2 structure endows superhydrophobicity with a contact angle up to 155.9°. The corrosion resistance of SHS and LIS coating is revealed by scanning Kelvin probe (SKP), electrochemical impedance spectroscopy (EIS) and potentiodynamic polarization (PDP) curves. Corrosion data show that the prepared LIS exhibits better corrosion resistance than SHS. After being soaked in a representative 3.5 wt% NaCl solution for 180 h, the corrosion inhibition efficiency of LIS maintains 99.6%, which is much better than that of SHS. In addition, when being fold or bent to induce cracks, the LIS shows slight change in corrosion inhibition efficiency, indicating the high tolerance to mechanical torsion. Moreover, in response to externally imposed mechanical scratching, LIS demonstrates good self-healing capability, illustrating the high potential for practical usage. [Display omitted] • Bioinspired coatings are prepared onto tin metal. • Liquid infused surface can heal itself due to fluidity. • Liquid infused surface protects tin from corrosion. [ABSTRACT FROM AUTHOR]

Atomic and close-to-atomic scale manufacturing is a new technology that can achieve atomic-level manufacturing precision and functional critical dimension. Here we propose an efficient approach for atomic-scale chemical mechanical polishing (CMP) surface of fine copper utilizing optimized CMP slurry and polishing parameters. The optimal polishing slurry is composed of silica, hydrogen peroxide, aspartic acid, sodium phosphate and deionized water, where abrasive particles of silica nanospheres synthesized are uniformly dispersed. Prior to CMP, copper was precisely lapped by ceria slurry. After CMP, the surface roughness is 0.099 nm with an area of 50 × 50 µm2. Atomic-level flatness surface is acquired. To the best of our knowledge, it is the lowest surface roughness with such a relatively large scanning area, compared with those published previously. High resolution transmission electron microscopy (HRTEM) images of polishing surface further prove that atomic-scale surface roughness is achieved. X-ray photoelectron spectra clarify CMP mechanism that complex oxidation, ionization and chelation are sparked on copper surface and the soft layer is formed. The presented efficient approach for atomic-scale polishing will widen the application fields of copper materials and copper-based components. [Display omitted] [ABSTRACT FROM AUTHOR]

Tin material corrosion has been recognized as an important problem for electronic products. Biomimetics strategies have been adopted to develop intriguing materials to combat corrosion. In this paper, by anodic oxidation, mussel inspired dopamine hydrochloride modification and thiol grafting, lotus leaf inspired superhydrophobic surface (SHS) based on porous SnO 2 coating is prepared on tin. Further, a stable liquid infused surface (LIS) enlightened by Nepenthes plant is formed by infusing dimethyl silicone oil into SHS. The wettability, microstructure and chemical composition of tin surface with different modification are characterized by contact angle, scanning electron microscopy (SEM), high resolution transmission electron microscopy (HRTEM), X-ray photoelectron spectroscopy (XPS) and so forth. The porous SnO 2 structure endows superhydrophobicity with a contact angle up to 155.9°. The corrosion resistance of SHS and LIS coating is revealed by scanning Kelvin probe (SKP), electrochemical impedance spectroscopy (EIS) and potentiodynamic polarization (PDP) curves. Corrosion data show that the prepared LIS exhibits better corrosion resistance than SHS. After being soaked in a representative 3.5 wt% NaCl solution for 180 h, the corrosion inhibition efficiency of LIS maintains 99.6%, which is much better than that of SHS. In addition, when being fold or bent to induce cracks, the LIS shows slight change in corrosion inhibition efficiency, indicating the high tolerance to mechanical torsion. Moreover, in response to externally imposed mechanical scratching, LIS demonstrates good self-healing capability, illustrating the high potential for practical usage. [Display omitted] • Bioinspired coatings are prepared onto tin metal. • Liquid infused surface can heal itself due to fluidity. • Liquid infused surface protects tin from corrosion. [ABSTRACT FROM AUTHOR]

Green and cost-effective technique for the preparation of silver nanoparticles stabilized with cinnamon's phytochemicals (CIN-AgNPs) as H 2 O 2 and xanthine nonozyme is described in the present study. Cinnamon's phytochemicals played the role of effective reducing agents as well as stabilizers of the silver. Nanoparticles were obtained in an optimum time of 90 min at room temperature. The optimum pH was found to be the normal pH of the plant extract (pH = 4.5). High Resolution Transmission Electron Microscopy (HRTEM) showed that most of the particles were regular spherical shaped with particle sizes ranging from 10.0 to 70.0 nm. The patterns were indexed as (111), (200), (220) and (311) reflections of the FCC silver crystal based on their d-spacing of 2.47, 2.13, 1.49 and 1.27 Å respectively. CIN-AgNPs test showed the peroxidase enzyme like activity in the absence of 3,3′,5,5′-tetramethylbenzidine (TMB), while the xanthine oxidase enzyme like activity is shown only when the CIN-AgNPs are combined with TMB. This combination was suitable for the detection of xanthine in the range of 1.0–28 µM with a detection limit of 0.48 µM and a limit of quantitation of 1.45 µM. While CIN-AgNPs test was suitable for the detection of H 2 O 2 without the need of TMB with a linear range from 4.7 nM to 25 µM with a limit of detection of 0.62 nM and limit of quantitation of 1.88 nM. [Display omitted] [ABSTRACT FROM AUTHOR]

Spinel LiMn 2 O 4 (LMO) positive material has the advantage of a robust structure with a three-dimensional network of channels for fast Li+ conduction, which is one of the hot topics in the zero-cobalt electrodes field of new energy technology. Nonetheless, the spinel LiMn 2 O 4 has serious transition metal dissolution as well as phase/surface stability problems, resulting in unsatisfactory cycle performance which hinders large scale applications in the field of lithium-ion batteries. In this study, Sm 2 O 3 surface modified LiMn 2 O 4 positive material is obtained by a facile ultrasonic cavitation combined with sol-gel strategy. The structural and surface morphological are analyses by X-ray diffraction, X-ray photoelectron spectroscopy and high resolution transmission electron microscopy illuminate the formation of the Sm 2 O 3 -coated LiMn 2 O 4. Electrochemical analysis revealed that the LMO particles coated by the 1 wt% Sm 2 O 3 is exhibited the best electrochemical performance among other coated and non-coated samples, with an initial capacity of 110.92 mAh g−1 and a capacity retention of 94.79% after 200 cycles. Furthermore, ICP analysis is showed that the manganese dissolution of the modified material in organic electrolyte is much lower than that of pristine sample. This work may provoke wide interests in surface modification areas and motivate the further improvement of the electrochemical performance for other commercialized spinel lithium ion batteries (LIBs). [Display omitted] [ABSTRACT FROM AUTHOR]

This work describes the synthesis of Ag decorated CoO nanocomposites (NCs) supported on chitosan (CS-Ag/CoO NCs) for simple, low cost and rapid colorimetric detection of L -cysteine, and for the photocatalytic reduction of hexavalent chromium (Cr(VI)) ion. The NCs was characterized thoroughly by using UV–vis spectrophotometer, fourier transform-infrared spectroscopy (FT-IR), high resolution transmission electron microscopy (HR-TEM), thermogravimetric analysis (TGA), X-ray diffraction spectroscopy (XRD), energy dispersive x-ray spectroscopy (EDAX), and X-ray photoelectron spectroscopy (XPS). The NCs displayed high specificity, sensitivity and selectivity towards the L -cysteine detection and quantification from aqueous samples. The limit of detection of the prepared probe was 4.67 nM. The particle size of CS-Ag/CoO NCs was found to be 8.52 ± 0.13 nm. The CS-Ag/CoO NCs interaction with L -cysteine, interestingly causes the aggregation of NCs with increase in particle size to 956 ± 0.23 nm. The color change was observed from yellow to color less. An excellent linear correlation exists between the absorbance vs logarithmic concentration of L -cysteine (10 nM- 1 mM). Here, 250 mg/L of NCs reduced 100 mg/L of Cr(VI) to Cr(III) within 180 min. The kinetic data suggested that the NCs exhibited greater photocatalytic reduction efficiency than CoO and Ag/CoO. The paper-based test strips were developed and applied for the rapid colorimetric assay for the onsite monitoring of L -cysteine from real samples. The study demonstrated a specific detection of L -cysteine irrespective of the source of samples using CS-Ag/CoO NCs. Hence, the prepared NCs can be used as a colorimetric probe and provides a practical application for photocatalytic reduction of Cr(VI). The NCs also exhibitted excellent antimicrobial activity. [Display omitted] [ABSTRACT FROM AUTHOR]

Here, CoFe 2 O 4 was loaded on Bi 2 O 3 via sonochemical technique to enhance the photocatalytic performance of Bi 2 O 3. The coexistence and crystallinity of CoFe 2 O 4 and Bi 2 O 3 was verified using X-ray powder diffraction (XRD). High resolution transmission electron microscopy (HRTEM) depicts attachment of CoFe 2 O 4 nanospheres on sheet-like Bi 2 O 3. Chemical states were examined using XPS. Visible light harvesting is facilitated by the narrow band gap (2.7 eV) of the nanocomposites (NCs). Reduced intensity in photoluminescence spectra indicates improved lifetime of electron/hole (e-/h+) pairs. The photocatalytic rate was boosted 3 – 3.75 times in NCs compared to pristine nanoparticles (NPs). The coupling of NPs resulted in type I heterojunction formation at the interface. The H 2 O was oxidized by h+ present in the valence band (VB) of CoFe 2 O 4 as it has higher positive potential and converted into hydroxyl radical (·OH). High resistance to photo-corrosion and stable performance of magnetically removed NCs was observed. The growth of Escherichia coli and Bacillus subtilis was inhibited upon NCs exposure. The operational simplicity and potential visible-light harvesting promote the usage of CoFe 2 O 4 -Bi 2 O 3 NCs in various sectors such as environmental remediation and antimicrobial application. Schematic representation of the photocatalytic mechanism of CoFe 2 O 4 -Bi 2 O 3 NCs [Display omitted] • CoFe 2 O 4 nanospheres loaded Bi 2 O 3 nanosheet was constructed. • Sonochemical assisted co-precipitation technique was adopted for synthesis. • The photocatalytic activity of NCs was enhanced by 3–3.75 times than individual NPs. • The OH· play major role in dye degradation. • The particles exhibited excellent antibacterial activity. [ABSTRACT FROM AUTHOR]

A novel eco-friendly, water soluble and effective corrosion inhibitor N, S-CDs was synthesized by hydrothermal method. The characterization of N, S-CDs was carried out by Fourier transformation infrared spectroscopy (FTIR), ultraviolet-visible spectroscopy (UV–vis) spectroscopy, photoluminescence (PL), Raman spectroscopy, X-ray photo electron spectroscopy (XPS) and high resolution transmission electron microscopy (HRTEM). The inhibitive effect of N, S-CDs on mild steel (MS) corrosion was evaluated by weight loss analysis, electrochemical impedance spectroscopy (EIS) and potentiodynamic polarization methods in 15% HCl solution. As per potentiodynamic polarization studies, studied inhibitor acts as mixed type inhibitor. Investigated N, S-CDs exhibited 98.64% of inhibition efficiency at 200 mg / L concentration and 303 K temperature. Investigated N, S-CDs corrosion inhibitor shows better corrosion inhibition efficiency as compared to the most of the similar type of corrosion inhibitors already reported in literature. The adsorption of N, S-CDs on MS surface followed Langmuir adsorption isotherm. The surface morphology of MS specimens was studied by scanning electron microscopy (SEM), atomic force microscopy (AFM) and contact angle measurement. [Display omitted] [ABSTRACT FROM AUTHOR]

In the present work, pulsed laser deposition of silver in open air is used to fabricate Ag nanoparticle (NP) films on the substrate without using flowing gas. The target was ablated by trains of nanosecond pulsed Nd:YAG laser beam. The deposited NP films on the substrate were characterized using field emission scanning electron microscopy (FESEM), high resolution transmission electron microscopy (HRTEM), and UV/Vis absorption spectroscopy. Surface plasmon resonance (SPR) characteristics of NPs were extracted from the data of UV/Vis spectrum. Mean size and size distribution of NPs were achieved by analyzing the FESEM images and using image processing technique. In order to show an application of the fabricated NP film in sensors, surface enhanced Raman spectroscopy (SERS) of NP films were inspected. The results of SERS show that the fabricated NP films can significantly enhance Raman signals. [Display omitted] • Ag nanoparticle films by pulsed laser deposition in open air were fabricated. • Deposition was performed in atmospheric pressure air without using flowing gas. • Surface plasmon resonance and size characteristics of NP films were investigated. • Higher laser fluences and number of pulses result in nanoparticles with larger size. • Fabricated NP films significantly enhance Raman signals in SERS application. [ABSTRACT FROM AUTHOR]

The effects of crystallization time and amount of Zeolitic Imidazolate Framework-8 (ZIF-8) on the photocatalytic activity of ZIF-8 decorated copper (Cu) doped titania (TiO 2) (ZIF-8/Cu-TiO 2) powders were investigated in this study. The formation of nanocomposite structure of ZIF-8 crystals grown over the surface of core Cu-TiO 2 particles containing heterojunction sites was observed at low ZIF-8 level. Powders containing ZIF-8 in the 5–46% range (weight basis) were synthesized and their activities in the photocatalytic degradation of an organic dye molecule were evaluated. X-ray diffraction (XRD), Fourier-transform infrared spectroscopy (ATR-FTIR), thermal gravimetric analysis (TGA), X-ray photoelectron spectroscopy (XPS) and high resolution transmission electron microscopy (HR-TEM) analyses indicated that ZIF-8/Cu-TiO 2 nanocomposite can be prepared at low levels of ZIF-8. HR-TEM images of 46% ZIF-8/Cu-TiO 2 showed that Cu-TiO 2 particles act as a core and ZIF-8 crystals grow over the surface of Cu-TiO 2 particles during crystal growth and Cu-TiO 2 particles were almost completely covered with ZIF-8 crystals. Photocatalytic activity increased with decreasing ZIF-8 level which was attributed to the formation of heterojunctions due to partial coverage of TiO 2 surface. The 1st order reaction rate constant of ZIF-8/Cu-TiO 2 nanocomposite containing 5% ZIF-8 was found to be 4 and 1.4 times that of bare ZIF-8 and Cu-TiO 2 , respectively. Partial coverage of TiO 2 surface with ZIF-8 crystals lead to the formation of light exposed ZIF-8/Cu-TiO 2 heterojunction sites for the enhanced degradation of the dye molecule. The presence of ZIF-8 in the nanocomposite also increased the adsorption of the organic dye by the interaction with open Zn2+ metal sites of ZIF-8 on the nanocomposite surface. This study revealed that ZIF-8/Cu-TiO 2 nanocomposites could be prepared at low ZIF-8 levels and short growth times with higher photocatalytic activities than their constituents and nanocomposites prepared at higher ZIF-8 levels and longer growth times. [Display omitted] • ZIF-8/Cu-TiO 2 heterojunction occurred at low ZIF-8 levels. • ZIF-8 in the ZIF-8/Cu-TiO 2 nanocomposite increased dye adsorption capacity. • ZIF-8/Cu-TiO 2 heterojunction enhanced charge carrier separation. • ZIF-8/Cu-TiO 2 showed higher photocatalytic activity than Cu-TiO 2 and ZIF-8. [ABSTRACT FROM AUTHOR]