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While cancel culture has become a social media buzzword, scholarly understanding of this phenomenon is still at its nascent stage. To contribute to a more nuanced understanding of cancel culture, this study uses a sequential exploratory mixed-methods approach by starting with in-depth interviews with social media users (n = 20) followed by a national online survey (n = 786) in Singapore. Through the interviews, we found that our participants understand cancel culture as more than just a mob engaged in public shaming on social media; it also involves perceptions of power imbalance and social justice. Building on these perspectives from our interviews, we tested the framework of theory of planned behavior in predicting intention to engage in cancel culture and expanded it by examining the effects of people's belief in a just world using an online national survey in Singapore. The analysis showed that attitude, subjective norms and perceived behavioral control were positively related to intention to engage in cancel culture, while general belief in a just world was a negative predictor. [ABSTRACT FROM AUTHOR]

A key point that Cones makes concerns inclusivity: the liturgy must be designed with the worshiping people with all their differences in mind, rather than only the majority. This means that some of his conclusions make sense only within those contexts as the rituals and liturgies he discusses are quite specific to these - for example, the idea of the liturgical presider playing the role of Christ in the liturgy is not one that is common across all liturgies. Cones points out that the gathered assembly as a symbol of the liturgy is a widely accepted point among liturgical theologians, although one that has been largely ignored as a theological source of inquiry. [Extracted from the article]

With 86.2% of tea production in Asia, teas consumed in other parts of the world are usually imported. The intricacies of the supply chain make tea vulnerable to fraudulent activities, highlighting the importance of ensuring authenticity and detecting fraud committed in teas. Conventionally, tea authentication is done by sensory evaluation. Moreover, the standardised chemical analysis techniques used for the evaluation of tea quality and authenticity are laborious. Thus, metabolomics, particularly the non-targeted metabolic fingerprinting approach, has been increasingly applied for high throughput authentication of tea. A brief overview of the metabolomics approach is provided. Then, this review delves into recent applications (i.e., from 2017 to 2023) of metabolomics to detect fraud committed in the form of mislabelling, substitution adulteration, and artificial enhancement. It concludes with future directions that could be undertaken. Targeted and non-targeted metabolomics were found to be largely successful in authenticating tea and detecting fraud. There is a growing interest in the use of non-targeted fingerprinting approach using rapid, non-destructive, and easy-to-use analytical platforms (e.g., vibrational spectroscopy, hyperspectral imaging). These techniques provide the possibility for high-throughput, large-scale, and point-of-site screening of teas. Nonetheless, more work on building a reliable database of chemical fingerprints/profiles for future authentication efforts and developing a tier-based approach for a confident confirmation of fraudulent activity perpetrated in tea is needed. • Tea is one of the food categories with high rates of fraud. • Metabolomics can complement conventional methods for tea authentication. • Metabolomics using rapid tools are useful for high-throughput screening of teas. • Metabolomics approaches to tackle various categories of tea fraud were detailed. [ABSTRACT FROM AUTHOR]

Levine reads the Yosef narrative through the lens of ASD, noting the similarity of Yosef's behaviors and experiences with those among ASD individuals, but is careful to note that he is not trying to make a clinical diagnosis of Yosef. Levine also gives a creditable attempt to glean lessons on interacting with ASD individuals, although much of it assumes unchanged social norms and philosophies from Yosef's time till today. The continued prominence of I na'ar i as a description of Yosef and his actions and the possible links of Yosef's wisdom to him being a I ben zekunim i were also repeatedly pointed out throughout the book, providing a coherent flow. [Extracted from the article]

• A highly efficient Cu/SiO 2 catalyst for non-oxidative dehydrogenation of ethanol. • Catalyst preparation by ammonia evaporation with optimum loading lends robustness. • High yields of acetaldehyde and hydrogen using 4.37% ethanol/Heat GHSV 8895 h−1. • Long catalyst lifetimewith minimal sintering and coking. While acetaldehyde is industrially produced in the Wacker process by homogeneous catalysts, a heterogeneous catalyst is so far elusive due to rapid deactivation stemming from metal sintering and coke formation. This work reports on a highly efficient, robust and stable Cu/SiO 2 catalyst for the non-oxidative dehydrogenation of ethanol prepared by the ammonia evaporation method. The highly dispersed Cu-particles are distinguished by outstanding thermal stability with very little sintering up to 600 °C. This was attributed to the strong interactions between the copper crystallites and SiO 2 arising from the intermediately formed copper phyllosilicate phase. Deactivation due to coke formation was successfully addressed by optimizing the metal loading. The CH x /Cu ratio in the used catalyst decreased by a factor of 10 as the copper loading was increased from 0.5 to 10 wt%. Samples with Cu ≥ 10 wt% demonstrated excellent activity of > 90% ethanol conversion and > 98% acetaldehyde selectivity with no observable deactivation for up to 500 h on-stream at 280 °C and a GHSV of 8895 h−1 (34,930 ml g-1h−1). [ABSTRACT FROM AUTHOR]

Abstract Japanese green tea is becoming increasingly popular worldwide due to its pleasant aroma. The volatiles of four types of Japanese green tea (Sencha, Matcha, Gyokuro, and Hojicha) were extracted separately by headspace solid-phase microextraction (HS-SPME) and solvent-assisted flavour evaporation (SAFE), and then analysed using gas chromatography-mass spectrometry (GC-MS). The aroma-active compounds in each type of green tea were identified by aroma extract dilution analysis (AEDA) of its SAFE extract. The odourants exhibiting the highest flavour dilution (FD) factor of 27 in Sencha were indole and methional. For Matcha, nonanal had the highest FD factor of 243. The odourant in Gyokuro with the highest FD factor of 27 was indole. For Hojicha, the odour-active compounds exhibiting high FD factor of 729 and 243 were 2,3-diethylpyrazine and 2,3-diethyl-5-methylpyrazine, respectively. Sensory evaluation was then done on the SAFE extract to understand the overall aroma profile of each type of green tea. Based on sensory evaluation results, steamed green teas (Sencha, Matcha, and Gyokuro) had leafier and higher floral notes while roasted green tea (Hojicha) showed higher roasty and woody notes. Finally, principal component analysis (PCA) of data obtained from GC-MS analysis demonstrated marked separation of these four types of Japanese green tea. Highlights • Volatiles from Japanese green tea extracted by headspace-solid phase microextraction. • Volatile from Japanese green tea extracted by solvent assisted flavour evaporation. • Identification of their key odourants by aroma extract dilution analysis. • Sensory evaluation of their solvent assisted flavour evaporation extracts. • Comparison of their volatile compositions by principal component analysis. [ABSTRACT FROM AUTHOR]

Magnetic skyrmions have emerged as promising elements for encoding information toward biomimetic computing applications due to their pseudoparticle nature and efficient coupling to spin currents. A key hindrance for skyrmionic devices is their instability against elongation at zero magnetic field (ZF). Prevailing materials approaches focused on tailoring skyrmion energetics have found ZF configurations to be highly sensitive, which imposes significant growth constraints and limits their device scalability. This work demonstrates that designer ZF skyrmion configurations can be robustly stabilized within chiral multilayer stacks by exploiting a duet of interlayer exchange couplings (IECs). Microscopic imaging experiments show that varying the two IECs enables the coarse and fine‐tuning of ZF skyrmion stability and density. Micromagnetic simulations reveal that the duo‐IEC approach is distinguished by its influence on the kinetics of skyrmion nucleation, in addition to the ability to tailor energetics, resulting in a substantially expanded parameter space, and enhanced stability for individual ZF skyrmions. This study underscores the importance of IEC as a means of stabilizing and controlling ZF skyrmions, paving the way to scalable skyrmion‐based devices. [ABSTRACT FROM AUTHOR]

[Display omitted] • Chemical fingerprints of Tieguanyin teas were obtained using ASAP-MS. • Key markers differentiating spring and autumn Tieguanyin teas were identified. • Four machine learning models built had high classification accuracies of up to 100%. • ASAP-MS is a viable rapid method to differentiate harvest seasons of Tieguanyi. Atmospheric solids analysis probe-mass spectrometry (ASAP-MS), an ambient mass spectrometry technique, was used to differentiate spring and autumn Tieguanyin teas. Two configurations were used to obtain their chemical fingerprints – ASAP attached to a high-resolution quadrupole time-of-flight mass spectrometer (i.e., ASAP-QTOF) and to a single-quadrupole mass spectrometer (i.e., Radian™ ASAP™ mass spectrometer). Then, orthogonal projections to latent structures-discriminant analysis was conducted to identify features that held promise in differentiating harvest seasons. Four machine learning models – decision tree, linear discriminant analysis, support vector machine, and k-nearest neighbour – were built using these features, and high classification accuracy of up to 100% was achieved. The markers were putatively identified using their accurate masses and MS/MS fragmentation patterns from ASAP-QTOF. This approach was successfully transferred to the Radian ASAP MS, which is more deployable in the field. Overall, this study demonstrated the potential of ASAP-MS as a rapid fingerprinting tool for differentiating spring and autumn Tieguanyin. [ABSTRACT FROM AUTHOR]

The acceptorless dehydrogenation of alcohols at low temperatures holds promise as a clean energy source and has been the subject of much research. In view of the thermodynamic limitations imposed by a positive Gibbs free energy, we examine the feasibility and extent of hydrogen formation from alcohol dehydrogenation using alumina-supported Ag catalysts. The results showed that in a closed system at 120 °C, the conversion of benzyl alcohol to benzaldehyde was limited by the available oxygen. The energetically demanding acceptorless route with hydrogen evolution contributed less than 2.5 % to the overall conversion. The presence of oxygen as an acceptor is vital for the progress of the reaction. In open systems even without an active influx of oxygen, alcohol dehydrogenation occurred readily but water was the main product rather than hydrogen. [ABSTRACT FROM AUTHOR]

Surface thiolation affects the size of gold nanoparticles and the presence of visible luminescence under UV stimulation. We explored these phenomena by analysing alkanethiolate coatings with different carbon chain lengths, from 3-mercaptopropionic acid to 16-mercaptohexadecanoic acid, synthesized by intense X-ray irradiation. Photoluminescence is present for the smallest nanoparticles, but its intensity becomes more intense as the carbon chain length increases, achieving a quantum efficiency of 28% with a 16-mercaptohexadecanoic acid coating. [ABSTRACT FROM AUTHOR]

Ambient mass spectrometry (AMS) is an emerging technique in food authenticity and traceability study due to the minimal sample preparation required and short analysis time. Herein, a non-targeted fingerprinting approach using an AMS technique, atmospheric solids analysis probe – mass spectrometry (ASAP-MS), was used to authenticate Chinese oolong teas. In the first part of the study, a total of 38 authentic samples from three main varieties – Guangdong Dancong, Taiwan Dongding, and Anxi Tieguanyin – were analysed and four discriminant analysis models were built using the fingerprint data from ASAP-MS. The principal component analysis-k nearest neighbour (PCA-kNN) model yielded the best classification outcome, where the classification accuracies of the training and validation sets were 100% and 92.6%, respectively. The second part of the study involved detecting possible adulteration of Anxi Tieguanyin, which is a high-value oolong tea under the register of protected geographical indication (PGI) of the European Union (EU). Adulteration of Anxi Tieguanyin was simulated by blending the authentic samples with 20–80% w/w of low-quality oolong teas. One-class modelling using data-driven soft independent modelling of class analogies (DD-SIMCA), with the Anxi Tieguanyin as the target class, was built using the fingerprint data of the authentic and adulterated samples. An excellent sensitivity of 100% and a high specificity of 98.1% were achieved, indicating that it is possible to detect substitution adulteration of Anxi Tieguanyin using ASAP-MS combined with one-class modelling. Overall, findings from this study exemplify the potential of ASAP-MS to be used for rapid, inexpensive, and high throughput classification of Chinese oolong tea varieties and screening for substitution adulteration of Anxi Tieguanyin oolong tea. [Display omitted] • Feasibility of authenticating Chinese oolong teas using ASAP-MS was investigated. • Varieties of Chinese oolong teas accurately classified using ASAP-MS and PCA-kNN. • Adulterated Anxi Tieguanyin teas were detected by ASAP-MS and DD-SIMCA. • ASAP-MS could be used for rapid detection of adulteration in Chinese oolong teas. [ABSTRACT FROM AUTHOR]

Carbon–SnO2core–shell hybrid nanofibers were prepared viasingle-spinneret electrospinning and subsequent heat treatment. The Kirkendall effect during the heat treatment is found to be responsible for the formation of core–shell morphology. The route is proven to be generic for fabrication of carbon–metal oxide or carbon–metal core–shell nanofibers, and corresponding nanotubes. [ABSTRACT FROM AUTHOR]

Barium Z-type hexaferrites (Ba 3 Co 2 Cr 2 x Fe 24−2 x O 41 with x = 0, 0.3, 0.6 and 0.9) were synthesised using solid state reaction technique. X-ray diffraction (XRD) analysis confirmed the formation of single phase Z-type hexaferrite structure. From transmission electron microscopy (TEM) analysis platelet morphologies were observed in all the studied samples and the average grain size were calculated, which were around 100 nm. Magnetisation measurements (M-H) and (M-T) were carried out using vibrating sample magnetometer (VSM). Saturation magnetisation (M s ) was found to decrease with increasing Cr content in the samples whereas, magnetic coercive field (H c ) and remanent magnetisation (M r ) were increased. Electromagnetic absorption properties of all the ferrite samples were tested in 2–18 GHz frequency range using Agilent Vector Network Analyser. The sample Ba 3 Co 2 Cr 1.2 Fe 22.8 O 41 (x = 0.6) had exhibited maximum microwave absorption of 99.8% at 5.34 GHz. All the samples showed broad absorption bandwidth of 3–3.2 GHz as well significantly high enough reflection loss of −10 dB. Therefore, the developed Z-type hexaferrites can be used for good electromagnetic shielding/absorber applications. [ABSTRACT FROM AUTHOR]

Electrocatalytic carbon monoxide reduction has been previously reported to yield a range of carbonaceous products including alcohols, hydrocarbons and carboxylic acids. However, esters, an important family of organic compounds, have not been formed. Herein, we report the electrosynthesis of C3 to C6 acetate esters (H3C−(C=O)−O−R) from carbon monoxide using copper catalysts in a membrane electrode assembly cell. Ethyl acetate and propyl acetate could be produced with an unprecedented total Faradaic efficiency (FE) of ∼22 % and with a current density of up to −55 mA cm−2, alongside minor quantities of methyl acetate and butyl acetate. The esters are produced via the addition reaction of ethenone (H2C=C=O) and alcohols produced during CO reduction. We show that the near water‐free reaction conditions and the high local pH play key roles in the formation of the esters. [ABSTRACT FROM AUTHOR]

Electrocatalytic carbon monoxide reduction has been previously reported to yield a range of carbonaceous products including alcohols, hydrocarbons and carboxylic acids. However, esters, an important family of organic compounds, have not been formed. Herein, we report the electrosynthesis of C3 to C6 acetate esters (H3C−(C=O)−O−R) from carbon monoxide using copper catalysts in a membrane electrode assembly cell. Ethyl acetate and propyl acetate could be produced with an unprecedented total Faradaic efficiency (FE) of ∼22 % and with a current density of up to −55 mA cm−2, alongside minor quantities of methyl acetate and butyl acetate. The esters are produced via the addition reaction of ethenone (H2C=C=O) and alcohols produced during CO reduction. We show that the near water‐free reaction conditions and the high local pH play key roles in the formation of the esters. [ABSTRACT FROM AUTHOR]

The potential of titanium (Ti) incorporation into cupric oxide (CuO) is demonstrated. The optical, electrical, microstructural, material quality, chemical composition, surface morphology, and photovoltaic properties of Ti doped CuO, CuO(Ti) have been systematically investigated. It is shown that Ti doped CuO reduces sheet resistance and improved the charge transport properties. Furthermore, by tuning the Ti concentration, the conductivity of CuO(Ti) can be improved, while retaining the optical properties and crystallinity of the samples. Heterojunction solar cells of p -type Ti doped CuO on n -type silicon (Si) substrate, p -CuO(Ti)/ n -Si, prepared by using conventional sputter deposition at room temperature followed by rapid thermal annealing at 300 °C to investigate the impact of Ti doped CuO on the performance of photovoltaic properties. The short circuit current and efficiency of p -CuO(Ti)/ n -Si heterojunction have been significantly improved compared to the cells without Ti doped CuO. [ABSTRACT FROM AUTHOR]

Magnetic skyrmions are topologically wound nanoscale textures of spins whose ambient stability and electrical manipulation in multilayer films have led to an explosion of research activities. While past efforts focused predominantly on isolated skyrmions, recently ensembles of chiral spin textures, consisting of skyrmions and magnetic stripes, are shown to possess rich interactions with potential for device applications. However, several fundamental aspects of chiral spin texture phenomenology remain to be elucidated, including their domain wall (DW) structure, thermodynamic stability, and morphological transitions. Here the evolution of these textural characteristics are unveiled on a tunable multilayer platform—wherein chiral interactions governing spin texture energetics can be widely varied—using a combination of full‐field electron and soft X‐ray microscopies with numerical simulations. With increasing chiral interactions, the emergence of Néel helicity, followed by a marked reduction in domain compressibility, and finally a transformation in the skyrmion formation mechanism are demonstrated. Together with an analytical model, these experiments establish a comprehensive microscopic framework for investigating and tailoring chiral spin texture character in multilayer films. [ABSTRACT FROM AUTHOR]

[Display omitted] • Mg incorporated into zeolite Beta framework by two-step postsynthesis procedure. • Rh3+/[MgO 4 ]2- electrostatic interactions stabilize single Rh atoms. • Catalytic efficiency of Rh/Mg-Beta due to low atomic coordination and basicity. • High selectivity in phenol hydrogenation to cyclohexanone at mild conditions. Nanoparticles are of interest in heterogeneous catalysis because of their excellent activity associated with atoms in a low coordination environment. However, their high reactivity becomes a drawback where selectivity is desired, compounded by their propensity towards agglomeration. Here, we show that stable subnanometric Rh particles can be prepared in a Mg-doped zeolite Beta based on the electrostatic interaction of the negatively charged zeolitic framework and the Rh3+ precursor. The Mg ions are incorporated into the zeolite framework whereas the Rh is located in the channels adjacent to the Mg. With only 0.27 and 0.5 wt% Mg and Rh, respectively, the Rh/Mg-Beta catalysts were highly active with > 94 % selectivity for the hydrogenation of phenol to cyclohexanone, an important intermediate for the production of Nylon. Key to the selectivity is the formation of the C=O double bond early in the reaction sequence, aided by the basicity of the Mg-Beta support. [ABSTRACT FROM AUTHOR]

Thegrowth mechanism of CeO2nanocrystals prepared bythe hydrothermal method has been studied in this article. The synthesisof CeO2nanocrystals follows two stages, the initial nucleationof CeO2nuclei and the subsequent ripening of nuclei inthe hydrothermal process. The nucleation involves the precipitationof Ce3熫抢 by OH–ions to form Ce(OH)3nanoparticles and the transition from Ce(OH)3to2–3 nm CeO2nuclei through an oxidation and rapiddehydration process. In the hydrothermal process, the oriented attachmentof nuclei through a lattice matched surface and subsequent Ostwaldripening results in the growth of CeO2nanocrystals. Thedominant mechanism for the ripening of nuclei in hydrothermal reactionsis the oriented attachment. The addition of polyvinylpyrrolidone surfactantand adjustment of solution acidity can promote the dispersion of thenuclei and enhance the effective collision among them in the hydrothermalstage, resulting in the oriented aggregation of particles and furthergrowth into larger CeO2nanocrystals (∼15 nm). Becauseof the low solubility of CeO2crystals in water, the Ostwaldripening process (dissolution/reprecipitation) only plays the secondimportant role in the hydrothermal reactions, which converts the assemblyclusters into nanocrystals with/without well-defined edges or contributesto the further growth of nuclei from 2–3 nm to 3–5 nm. [ABSTRACT FROM AUTHOR]

Surveillance of nosocomial infections, like catheter-associated urinary tract infection (CAUTI), central line-associated bloodstream infection, possible ventilator-associated pneumonia and secondary bloodstream infections were observed to study the impact of COVID-19 outbreak in ICUs from Tan Tock Seng Hospital and National Centre for Infectious Diseases, Singapore between February and June 2020. Higher nosocomial infection rates were observed in COVID-19 patients, although it was not statistically significant. Moreover, COVID-19 patients seem to be more predisposed to CAUTI despite a higher proportion of non-COVID-19 patients having urinary catheters. Thus, continued vigilance to ensure adherence to IPC measures is needed. [ABSTRACT FROM AUTHOR]

[Display omitted] • Rapid crystallization of Zr-Beta with high Zr content possible with MCLA protocol. • Zr-Beta formed with high crystallinity and hydrophobicity. • High Zr loadings useful in MPV reduction of sterically hindered ketones and diones. • MCLA-synthesized Zr-Beta is less susceptible to poisoning by water adsorption. Heteroatom-incorporated zeolite catalysts are critical for biomass utilization and feedstock valorization in green chemistry. Key features are adjustable acidity, high stability, and a tailored range of functionalities. However, an environmentally benign synthesis of zeolites with good crystallinity and especially with high levels of metal substitution into the lattice remains challenging. Here, we propose a mechanochemistry-based liquid-assisted method (MCLA) for Zr-incorporated Beta zeolites that is high yielding, facile and sustainable. Compared with the fluoride-mediated hydrothermal method, crystallization times were considerably shortened so that Si-Beta and Zr-Beta (Si/Zr 100) zeolites can be synthesized within 9 and 15 h, respectively. Using the MCLA route, Beta zeolites with Zr loading up to 10.4 wt% (Si/Zr 12.5) were obtained. The materials have excellent catalytic activity for Meerwein-Ponndorf-Verley reductions with much higher water tolerance compared to Zr-Beta prepared by the post-synthesis method. The hydrophobic nature of the MCLA-synthesized zeolites makes them particularly useful as catalysts for organic reactions. [ABSTRACT FROM AUTHOR]

Natural fibers are a class of thread-like bio-based materials with merits of favorable mechanical properties, low cost, and minimal environmental impact, etc. Endowing additional functionalities to natural fibers would further encourage greater utilization of these renewable materials. In this work, we present a new strategy to integrate ultrasmall (<3 nm) gold nanoclusters (AuNC) with coconut fibers (coir), which resulted in a unique fluorescence switchable composite material. Specifically, we demonstrate that the delignified, green-emissive coir can act as a heterogeneous reducing and nucleating agent to form luminescent AuNC. The immobilization of AuNC switches the intrinsic green emission of delignified coir into enhanced orange emission of the resultant composite material. Our further investigations suggest that the fluorescence switching is governed by the Förster resonance energy transfer (FRET) process despite their disparity in material type, morphology, and size. Several important parameters, such as the FRET efficiency (E), rate constant (k T), the Förster radius (R 0) and the distance between donor-acceptor pair (R DA) were estimated to describe the FRET process. The distance-sensitive FRET process was also confirmed by varying the medium between the AuNC and delignified coir, which highlighted the potential uses in stimuli-responsive sensor applications. We expect that this strategy can be extended to rationally design functional nature-based materials from various sources. • Green-emissive coconut fibres (coir) are obtained by chlorite delignification. • Luminescent gold nanoclusters are formed in-situ on delignified coir. • Resonance energy transfer from coir boosts the fluorescence of gold nanoclusters. • Fluorescence switching is achieved by simple variation of medium. [ABSTRACT FROM AUTHOR]

Revealing the “structure–property” relationship is nontrivial for the application of materials. The magnetic configurations of FeGe are strongly dependent on the internal structures and positions of Fe and Ge atoms, e.g., B20-type cubic phase configuring into magnetic skyrmions. Although endotaxial FexGe islands on (001)Ge substrate can be obtained with a dynamically controlled growth process, it is not possible to obtain the crystal structural information from conventional approaches, such as X-ray diffraction or 2D electron diffractions due to the embedded growth structures at the nanometer scale, which are too small to be probed. Through a 3D rotational electron diffraction method combined with high resolution transmission electron microscopy, we have successfully determined the specific phase of each FexGe island on the Ge substrate. Three major phases (two hexagonal and one monoclinic) were found existing in the FexGe islands with nearly equal probability and independent of the deposition temperatures and time. All the islands with different phases were inclined to {111}Ge planes, which was due to a comparatively higher energy barrier for Fe atom diffusion through {111}Ge than other Ge planes. The epitaxial growth relationship at the interface was as follows: FeGemono(4−2−1)//Ge(111), FeGemono[15−6]//Ge[1−10], Fe3Ge2(201)//Ge(111) and Fe3Ge2[−112]//Ge[1−10], Fe13Ge8(40−1)//Ge(111) and Fe13Ge8[124]//Ge[1−10]. Ferromagnetism for the as-deposited samples was observed via SQUID, which most probably is attributed to the hexagonal FeGe phases. [ABSTRACT FROM AUTHOR]

High quality rutile Ti 1- x Sn x O 2 nanofilms were successfully grown in a layer-by-layer mode at a moderately low temperature of 400 °C using pulsed laser deposition (PLD). High solid solubility of up to x = 0.216 has been achieved in the Ti 1- x Sn x O 2 films despite theoretical prediction by Density functional theory (DFT) of large formation energy (∼5.64 eV) required for the substitutional alloy to exist at such high Sn concentration. The resultant films have smooth interfaces and step-terraced surfaces with well controlled stoichiometry and are optically transparent. Sn L 3 -edge Extended X-ray absorption fine structure (EXAFS) reveals the substitution of Sn 4+ in the Ti 4+ lattice sites of TiO 2 . The lattice spacing along [110] increases linearly with increment in x due to substitution of Sn 4+ ions in the Ti lattice sites of the Ti 1- x Sn x O 2 films. X-ray photoelectron spectroscopy (XPS) and Rutherford backscattering (RBS) show that Sn is uniformly distributed on the surface and in the bulk of the films. These results are crucial when considering Ti 1- x Sn x O 2 with suitable composition for making TiO 2 based quantum structures in advanced optoelectronic devices and solar energy materials, where high-quality crystalline thin film-substrates are important. [ABSTRACT FROM AUTHOR]

Room temperature growth of HfO 2 thin film on clean 2H-MoS 2 via plasma-sputtering of Hf-metal target in an argon/oxygen environment was studied in-situ using x-ray photoelectron spectroscopy (XPS). The deposited film was observed to grow akin to a layer-by-layer growth mode. At the onset of growth, a mixture of sulfate- and sulfite-like species (SO x 2− where x = 3, 4), and molybdenum trioxide (MoO 3 ), are formed at the HfO 2 /MoS 2 interface. An initial decrease in binding energies for both Mo 3d and S 2p core-levels of the MoS 2 substrate by 0.4 eV was also observed. Their binding energies, however, did not change further with increasing HfO 2 thickness. There was no observable change in the Hf4f core-level binding energy throughout the deposition process. With increasing HfO 2 deposition, MoO 3 becomes buried at the interface while SO x 2− was observed to be present in the film. The shift of 0.4 eV for both Mo 3d and S 2p core-levels of the MoS 2 substrate can be attributed to a charge transfer from the substrate to the MoO 3 /SO x 2− -like interface layer. Consequently, the Type I heterojunction valence band offset (conduction band offset) becomes 1.7 eV (2.9 eV) instead of 1.3 eV (3.3 eV) expected from considering the bulk HfO 2 and MoS 2 valence band offset (conduction band offset). The formation of these states and its influence on band offsets will need to be considered in their device applications. [ABSTRACT FROM AUTHOR]

Currently, the production of hierarchical 2 D layered carbon is mostly limited by low yields, laborious processing, and the high tendency for reaggregation. Hence, it is still a challenge to attain stable porous carbon structures with a well-preserved layered structure and hierarchical pores. Here, we demonstrate a facile and simultaneous activation-exfoliation-reassembly technique to perform structural modification and pore tailoring of carbonaceous matrices conveniently. Various pore creations can be realized concurrently from in-plane micro-/mesopores by chemical activation, expansion of intersheet mesopores, and interconnectivity of the layered structure to form 3 D macropores. Finally, a proof-of-concept demonstration of the combination of hierarchical macro-/micro-/mesoporous layered carbon structure and TiO2 nanosheets shows promising adsorption and catalytic properties. [ABSTRACT FROM AUTHOR]

Colloidal deposition of gold nanoparticles (Au NPs) onto NH2-UiO-66 nanocrystals has been demonstrated with the resulting hybrid catalyst proving robust and versatile for one-pot, heterogeneous conversions involving the selective oxidation of primary alcohols in tandem with Knoevenagel condensation reactions. Within these systems, structure–property correlations have been established to confirm that the active sites for the oxidation and condensation reactions are intrinsically correlated with the Au NPs and pendant amine groups respectively. [ABSTRACT FROM AUTHOR]

Aluminum-doped cupric oxide (CuO:Al) was prepared via an out-diffusion process of Al from an Al-coated substrate into the deposited CuO thin film upon thermal treatment. The effect of the annealing temperature on the structural and optical properties of CuO:Al was investigated in detail. The influence of Al incorporation on the photovoltaic properties was then investigated by preparing a p-CuO:Al/n-Si heterojunction solar cell. A significant improvement in the performance of the solar cell was achieved by controlling the out-diffusion of Al. A novel in situ method to co-dope CuO with Al and titanium (Ti) has been proposed to demonstrate CuO-based solar cells with the front surface field (FSF) design. The FSF design was created by depositing a CuO:Al layer followed by a Ti-doped CuO (CuO:Ti) layer. This is the first successful experimental demonstration of the codoping of a CuO thin film and CuO thin film solar cells with the FSF design. The open circuit voltage (Voc), short circuit current density (Jsc) and fill factor (FF) of the fabricated solar cells were significantly higher for the FSF device compared to devices without FSF. The FF of this device improved by 68% through the FSF design and a record efficiency ɳ of 2% was achieved. The improvement of the solar cell properties is mainly attributed to the reduction of surface recombination, which influences the charge carrier collection. [ABSTRACT FROM AUTHOR]

In the present study, we report the synthesis of a high-quality, single-crystal hexagonal β-Co(OH)2 nanosheet, exhibiting a thickness down to ten atomic layers and an aspect ratio exceeding 900, by using graphene oxide (GO) as an exfoliant of β-Co(OH)2 nanoflowers. Unlike conventional approaches using ionic precursors in which morphological control is realized by structure-directing molecules, the β-Co(OH)2 flower-like superstructures were first grown by a nanoparticle-mediated crystallization process, which results in large 3D superstructure consisting of ultrathin nanosheets interspaced by polydimethoxyaniline (PDMA). Thereafter, β-Co(OH)2 nanoflowers were chemically exfoliated by surface-active GO under hydrothermal conditions into unilamellar single-crystal nanosheets. In this reaction, GO acts as a two-dimensional (2D) amphiphile to facilitate the exfoliation process through tailored interactions between organic and inorganic molecules. Meanwhile, the on-site conjugation of GO and Co(OH)2 promotes the thermodynamic stability of freestanding ultrathin nanosheets and restrains further growth through Oswald ripening. The unique 2D structure combined with functionalities of the hybrid ultrathin Co(OH)2 nanosheets on rGO resulted in a remarkably enhanced lithium-ion storage performance as anode materials, maintaining a reversible capacity of 860 mA h g−1 for as many as 30 cycles. Since mesocrystals are ubiquitous and rich in morphological diversity, the strategy of the GO-assisted exfoliation of mesocrystals developed here provides an opportunity for the synthesis of new functional nanostructures that could bear importance in clean renewable energy, catalysis, photoelectronics, and photonics. [ABSTRACT FROM AUTHOR]

Abstract: In the present study, hierarchical α-Fe2O3/SnO2 hollow heterostructures were successfully synthesized by a template growth method. The crystal structure, morphology, composition and surface area of obtained heterostructures were characterized by X-ray diffraction, scanning electron microscopy, transmission electron microscopy, X-ray photoelectron spectroscopy and BET surface area analysis. The results reveal that [001]-directed SnO2 nanorods grow on the side surface of the [001]-directed α-Fe2O3 hollow nanotubes/nanorings, forming and interfaces. These heterostructures can be further converted into magnetic γ-Fe2O3/SnO2 heterostructure without any significant change in morphology. These α-Fe2O3/SnO2 hollow heterostructures exhibit much higher photocatalytic activities for degradation of methylene blue in comparison with that of pure α-Fe2O3 nanotubes/nanorings in the wide spectral region from UV to visible due to both larger surface area and improved electron–hole separation efficiency in the interface of heterostructure. [Copyright &y& Elsevier]

Abstract: An original synthesis method based on X-ray irradiation produced gold nanoparticles (AuNPs) with two important properties for biomedical research: intense visible photoluminescence and very high accumulation in cancer cells. The nanoparticles, coated with MUA (11-mercaptoundecanoid acid), are very small (1.4nm diameter); the above two properties are not present for even slightly larger sizes. The small MUA-AuNPs are non-cytotoxic (except for very high concentrations) and do not interfere with cancer cell proliferation. Multimodality imaging using visible light fluorescence and X-ray microscopy is demonstrated by tracing the nanoparticle-loaded tumor cells. [Copyright &y& Elsevier]

Nanosheet building blocks in flower ‐ like mesocrystals are interspaced by organic additives and held together by complex inter ‐ sheet interactions. Therefore, the ability to exfoliate mesocrystals requires an appropriate modifier that can interact with the organic additive and weaken the interaction between the nanosheets. In their Full paper on page 12444 ff., S. Deng, H. ‐ M. Fan et al. show that graphene oxide (GO), a quasi ‐ two ‐ dimensional (2D) structure tethered with abundant functional groups with dual molecular ‐ colloidal properties, acts as an exfoliant of the mesocrystals. [ABSTRACT FROM AUTHOR]