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Crude palm oil (CPO) is rich with phytonutrients such as carotenoids and tocols which possesses many health benefits. The aim of this research was to develop a methanol-free process to produce palm phytonutrients via enzymatic hydrolysis. In this work, triacylglycerol was hydrolyzed into free fatty acids (FFAs) using three different types of liquid lipases derived from Aspergillus oryzae (ET 2.0), Aspergillus niger (Habio) and Candida antartica (CALB).ET 2.0 was found to be the best enzyme for hydrolysis. Under the optimum condition, the FFA content achievable was 790 g kgThis work shows that enzymatic hydrolysis, which is inherently safer, cleaner and sustainable is feasible to replace the conventional methanolysis for the production of palm phytonutrients. © 2022 The Authors. Journal of The Science of Food and Agriculture published by John WileySons Ltd on behalf of Society of Chemical Industry.

Sludge palm oil is a by-product produced as a result of oil loss into waste streams during the palm oil milling process. It is non-edible, inexpensive and abundantly available, thus making it an attractive feedstock for biodiesel production. However, it contains high contents of water and free fatty acids, rendering the conventional alkali-catalyzed process unsuitable. Therefore, this research aimed to improve the production of biodiesel from sludge palm oil using a low-cost liquid lipase (Eversa® Transform 2.0) produced from a genetically modified Aspergillus oryzae. The activity of the liquid lipase was determined to be 9600 IU mL−1. We performed the reaction using low-input process conditions with only 0.2 wt% enzyme concentration and 5:1 methanol-to-oil molar ratio at a low operating temperature of 45 °C. Under an optimum stirring speed of 750 rpm, a crude biodiesel with a high ester content of approximately 94 wt% could be produced. Additionally, the crude glycerol produced has a higher purity compared to that produced via a chemical-catalyzed process. Overall, an economical and sustainable enzymatic process for the conversion of sludge palm oil into high quality biodiesel and glycerol has been demonstrated in this study.

Reducing the lateral scale of two-dimensional (2D) materials to one-dimensional (1D) has attracted substantial research interest not only to achieve competitive electronic applications but also for the exploration of fundamental physical properties. Controllable synthesis of high-quality 1D nanoribbons (NRs) is thus highly desirable and essential for further study. Here, we report the implementation of supervised machine learning (ML) for the chemical vapor deposition (CVD) synthesis of high-quality quasi-1D few-layered WTe2 NRs. Feature importance analysis indicates that H2 gas flow rate has a profound influence on the formation of WTe2, and the source ratio governs the sample morphology. Notably, the growth mechanism of 1T' few-layered WTe2 NRs is further proposed, which provides new insights for the growth of intriguing 2D and 1D tellurides and may inspire the growth strategies for other 1D nanostructures. Our findings suggest the effectiveness and capability of ML in guiding the synthesis of 1D nanostructures, opening up new opportunities for intelligent materials development.

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Cocatalyst design is a key approach to acquire high solar-energy conversion efficiency for photocatalytic hydrogen evolution. Here a new in situ vapor-phase (ISVP) growth method is developed to construct the cocatalyst of 2D PtS nanorectangles (a length of ∼7 nm, a width of ∼5 nm) on the surface of g-C3N4 nanosheets. The 2D PtS nanorectangles/g-C3N4 nanosheets (PtS/CN) show an unusual metal sulfide–support interaction (MSSI), which is evidenced by atomic resolution HAADF-STEM, synchrotron-based GIXRD, XPS and DFT calculations. The effect of MSSI contributes to the optimization of geometrical structure and energy-band structure, acceleration of charge transfer, and reduction of hydrogen adsorption free energy of PtS/CN, thus yielding excellent stability and an ultrahigh photocatalytic H2 evolution rate of 1072.6 μmol h−1 (an apparent quantum efficiency of 45.7% at 420 nm), up to 13.3 and 1532.3 times by contrast with that of Pt nanoparticles/g-C3N4 nanosheets and g-C3N4 nanosheets, respectively. This work will provide a new platform for designing high-efficiency photocatalysts for sunlight-driven hydrogen generation.

It is highly desired yet challenging to steer the CO

Light utilization largely governs the performance of CO

Increasing oily wastewater and frequent oil leakage accidents have become a serious global environmental problem. To improve the adsorption capacity and simplify the recovery process of crude oil, it is a great significance to develop various advanced oil adsorbents and oil-collecting devices. In this work, a lightweight and compressible three-dimensional (3D) g-C3N4/poly(vinyl alcohol) (PVA) nanosheet-based aerogel was successfully fabricated. The resulting 3D g-C3N4/PVA nanosheet-based aerogel has the advantages of high porosity and good hydrophobicity, making it a suitable material for use as an adsorbent. The 3D g-C3N4/PVA nanosheet-based aerogel can absorb various oils and organic solvents as high as 228-695 times its weight. Moreover, aerogel regeneration and recovery of oil can be achieved by cyclic distillation, squeezing, or combustion. After 40 cycles, the structure of 3D g-C3N4/PVA nanosheet-based aerogels are well kept and the adsorption capacity still retained 95, 93, and 95% by distillation, squeezing, and combustion, respectively. 3D g-C3N4/PVA nanosheet-based aerogel as an adsorbent has great potential in the application of oil/water separation for the removal of pollutants. This work was supported by the National Natural Science Foundation of China (51902222) and the National Natural Science Foundation of China (21606113).

The effect of surface tensile strain on the photocatalysis is an open question. In this work, strain engineering has been demonstrated to promote the performance of photocatalysis by curved 2D mate...

Ultra-small MoS2 quantum dots (QDs) with an average size of 2.48 nm coated on Au nanoparticles with a core-satellite structure (Au/MoS2 QDs) are successfully prepared by a self-assembly strategy through the strong bonding between Au and S. Benefited from the unique structure, the Au/MoS2 QDs hybrid exhibits outstanding electrocatalytic performance toward hydrogen evolution reaction (HER). The Au/MoS2 QDs hybrid needs overpotentials of 112, 146, and 206 mV to approach current densities of 10, 20, and 50 mA·cm−2 in 0.5 mol·L−1 H2SO4 (pH = 0.3), respectively. And a low Tafel slope (83 mV·dec−1) is obtained. The catalyst also displays satisfactory stability and durability, indicating a negligible current density loss after 20 h of electrolysis. The high hydrogen generation activities and stability are attributed to the great number of active sites, high conductivity and synergistic effects between gold nanoparticles (Au NPs) and MoS2 QDs. Last but not least, this strategy opens up a favorable way to combine MoS2 QDs with other metals.

MoS2 nanomaterial with the micro-pompon structure was synthesized by a surfactant-assisted hydrothermal method. The morphologies and structures of as-prepared MoS2 micro-pompon were investigated by adding different types of surfactants such as cetyltrimethyl ammonium bromide (CTAB), sodium dodecylbenzene sulphonate (SDBS), and polyvinyl pyrrolidone (PVP). The results indicated that the morphology of MoS2 could be controlled and changed effectively by the cationic surfactant of CTAB. A reasonable growth mechanism for hollow structured MoS2 micro-pompon by hydrothermal processes was proposed. Further, photocatalytic degradation properties of MoS2 micro-pompon under visible light were evaluated by degradation of common organic dyes, which include rhodamine B (RhB), congo red, methyl orange, and methylene blue. The results indicated that MoS2 micro-pompon owned the highly selective catalytic ability to RhB with degradation efficiency of 95% in 60 min and 68% in 30 min. With the additive of the surfactant, the MoS2-CTAB sample exhibited an enhanced ability of photocatalytic activity where degradation efficiency was improved to 92% in 30 min. The method employed in this work could be expanded to fabricate other sulfides with the controllable morphology and structure to further regulate the photocatalytic performance.

In recent years, two‐dimensional (2D) ternary materials have attracted wide attention due to their novel properties which can be achieved by regulating their chemical composition with a very great degree of freedom and adjustable space. However, as for the precise synthesis of 2D ternary materials, great challenges still lie ahead that hinder their further development. In this work, we demonstrated a simple and reliable approach to synthesize 2D ternary‐layered BiOCl crystals through a microwave‐assisted space‐confined process in a short time (

The geometrically multiplied development of 2D MXenes has already promoted the prosperity of various fields of scientific researches especially but not limited in energy storage and conversion. Notably, cation intercalation can improve the interlayer spacing of MXenes resulting in tunable physical and chemical properties. Moreover, the synchrotron radiation X-ray characterizations have also shown high potential on exploring the property and structure of cation intercalated MXenes. This review is mainly focused on the recent achievements of cation intercalated MXenes through different methods on energy storage systems. Synchrotron-based X-ray absorption spectroscopic characterizations are emphasized to probe the local coordination and electronic structure in intercalated MXenes. The outlook of cation intercalation on MXenes and their applications are also discussed.

As the continuation and advances in traditional BiOX (X = Cl, Br, I), bismuth-rich bismuth oxyhalides (BiaObXc) show distinct differences in the surface local atomic structure, electronic structure, optical properties, and electrical conductivity relative to BiOX. These features endow bismuth-rich BiaObXc with more tunable properties to achieve excellent photocatalytic performance. Here, the state-of-the-art progress in bismuth-rich bismuth oxyhalides is reviewed to clarify the key structure–activity relationship for enhanced photocatalytic performance. Various methods for the controllable synthesis and formation mechanism of bismuth-rich BiaObXc are presented. Different strategies to tailor the photocatalytic behaviors are summarized, namely thickness tuning, morphological control, heteroatom doping, surface defect engineering, single atom engineering, surface modification, preparation of a solid solution and engineering of semiconductor heterojunctions. Moreover, the recent advances in BiaObXc for diversified photocatalytic applications, such as H2 generation, O2 production, CO2 reduction, N2 reduction, organic synthesis and pollutant removal, are summarized. Finally, the existing challenges and perspectives are also presented to bring about new opportunities for future research.

Three-dimensional (3D) aerogels have attracted more and more attention in oil–water separation, due to their advantages of low density, high porosity, and large specific surface area. However, their application is greatly limited due to their hydrophilic and low adsorption properties. In this work, we report a 3D MoS2–polyvinylpyrrolidone (PVP) aerogel, prepared by a freeze-drying method, where PVP was used as a skeleton to support the aerogel. As a surfactant, PVP can easily attach to the surface of MoS2 nanosheets and facilitate the interconnection between nanosheets. The 3D MoS2–PVP aerogel exhibits low density, high porosity, good hydrophobicity, and excellent adsorption capacity (195–649 times). Moreover, after 30 cycles, the structure of the 3D MoS2–PVP aerogel is well kept and the adsorption capacity is still retained, at 93.5% and 92.9%, by squeezing and distillation, respectively. Therefore, the obtained 3D MoS2–PVP aerogel is a promising adsorption material and has great practical application potential in oil–water separation.

Metal nanostructures with high atom utilization, abundant active sites, and special electron structures should be beneficial to the electrochemical monitoring of hydroquinone (HQ), a highly toxic environmental pollutant. However, traditional nanostructures, especially non-noble metals generally suffer from severe aggregation, or consist of a mixture of nanoparticles and nanoclusters, resulting in low detection sensitivity. Herein, we precisely control the size of Mo-based nanostructures spanning four scales (viz. Mo

Cocatalyst design is a key approach to acquire high solar-energy conversion efficiency for photocatalytic hydrogen evolution. Here a new in situ vapor-phase (ISVP) growth method is developed to construct the cocatalyst of 2D PtS nanorectangles (a length of ∼7 nm, a width of ∼5 nm) on the surface of g-C

Reducing the lateral scale of two-dimensional (2D) materials to one-dimensional (1D) has attracted substantial research interest not only to achieve competitive electronic applications but also for the exploration of fundamental physical properties. Controllable synthesis of high-quality 1D nanoribbons (NRs) is thus highly desirable and essential for further study. Here, we report the implementation of supervised machine learning (ML) for the chemical vapor deposition (CVD) synthesis of high-quality quasi-1D few-layered WTe

A carbon microtube aerogel (CMA) with hydrophobicity, strong adsorption capacity, and superb recyclability was obtained by a feasible approach with economical raw material, such as kapok fiber. The CMA possesses a great adsorption capacity of 78-348 times its weight. Attributed to its outstanding thermal stability and excellent mechanical properties, the CMA can be used for many cycles of distillation, squeezing, and combustion without degradation, which suggests a potential practical application in oil-water separation. In addition, the adsorption capacity still retained 98% by distillation, 97% by squeezing, and 90% by combustion after 10 cycles. Therefore, the obtained CMA has a broad prospect as an economical, efficient, and environmentally friendly adsorbent. National Research Foundation (NRF) This work was financially supported by Singapore National Research Foundation under NRF RF Award No. MOE2016- T2-1-131, Tier 1 2017-T1-001-075.

Room temperature Na-ion batteries (SIBs) show great potential for use as renewable energy storage systems. However, the large-scale application of SIBs has been hindered by the lack of an ideal SIBs anode material. We synthesized MoS2 on carbonized graphene-chitosan (G-C) using the hydrothermal method. The strong interaction between the MoS2 and the G-C greatly improved the electron transport rate and maintained the structural stability of the electrode, which lead to both an excellent rate capability and long cycle stability. The G-C monolith was proven to enhance the electrical conductivity of the composites and served as a matrix for uniformly dispersing active MoS2 nanosheets (NSs), as well as being a buffer material to adapt to changes in volume during the cycle. Serving as an anode material for SIBs, the MoS2-G-C electrode showed good cycling stability (527.3 mAh g−1 at 100 mA g−1 after 200 cycles), excellent rate capability, and a long cycle life (439.1 mAh g−1 at 1A g−1 after 200 cycles). Keywords: Na-ion batteries, Carbon-based materials, MoS2, Long cycle life

Surface defects in semiconductors have a significant role to tune the photocatalytic reactions. However, the dominant studied defect type is oxygen vacancy, and metal cation vacancies are seldom ex...

The emerging ultrathin materials with a suitable energy band structure have been regarded as a new type of photocatalyst. Among them, bismuth-based ultrathin materials display intriguing photocatalytic performance due to the unique structural and electronic properties, strong light response and appealing energy band structure. This critical review summarizes recent progress in the design and tailoring of diversified Bi-based ultrathin materials for various photocatalytic applications. We start with the introduction from the crystal structure, materials design and synthesis of various Bi-based ultrathin photocatalysts, such as bismuth oxide, bismuth oxyhalides, Bi2WO6, Bi2MoO6, BiVO4 and so on. Then, strategies for local atomic arrangement, electronic structure, and carrier concentration tuning, so as to boost the performance, are summarized, such as crystal facet control, bismuth-enrichment strategy, surface adjustment, heteroatom doping, defect engineering, co-catalyst modification, and utilization of solid solutions, single atoms, and heterojunctions. Furthermore, advancements of versatile photocatalytic applications over Bi-based ultrathin materials are discussed, including oxygen evolution, hydrogen evolution, organic syntheses, CO2 reduction, N2 reduction, and pollutant removal, with an emphasis on the structure–activity relationship. Finally, the existing challenges and future research opportunities are also presented.

Metal oxide hierarchical heterostructures (HHSs) for gas sensors with controllable and novel nanostructures have attracted tremendous attention due to their multi-junction, multi-phase, interfacial and synergic effects. Based on various metal oxide materials, multifarious hierarchical nanostructures and heterostructures can be constructed to enhance the sensor performances of the primary structures. Herein, SnO2/ZnO HHSs are successfully prepared via a fast, simple, and low-cost microwave-assisted hydrothermal (MWAH) approach. The epitaxial growth of SnO2 nanorods on ZnO nanoflowers formed hierarchical structures that are conducive to promoting sensor performance. The detection limit is 2 ppb for NO2 based on the SnO2/ZnO HHSs. The sensor response toward 10 ppm NO2 is 52.3, which is 5 and 10 times higher than those of SnO2 and ZnO. The response and recovery times of SnO2/ZnO HHSs are 16 and 10 s, respectively. We believe that the strategy of synthesizing metal oxides with HHSs based on the MWAH method provides novel insight into the next generation of gas sensors.

Numerous epidemiological studies have shown a close relationship between outdoor air pollution and increased risks for cancer, infection, and cardiopulmonary diseases. However, very few studies have investigated the potential health effects of coexposure to airborne particulate matter (PM) and bioaerosols through the transmission of infectious agents, particularly under the current circumstances of the coronavirus disease 2019 pandemic. In this study, we aimed to identify urinary metabolite biomarkers that might serve as clinically predictive or diagnostic standards for relevant diseases in a real-time manner. We performed an unbiased gas/liquid chromatography-mass spectroscopy (GC/LC-MS) approach to detect urinary metabolites in 92 samples from young healthy individuals collected at three different time points after exposure to clean air, polluted ambient, or purified air, as well as two additional time points after air repollution or repurification. Subsequently, we compared the metabolomic profiles between the two time points using an integrated analysis, along with Kyoto Encyclopedia of Genes and Genomes-enriched pathway and time-series analysis. We identified 33 and 155 differential metabolites (DMs) associated with PM and bioaerosol exposure using GC/LC-MS and follow-up analyses, respectively. Our findings suggest that 16-dehydroprogesterone and 4-hydroxyphenylethanol in urine samples may serve as potential biomarkers to predict or diagnose PM- or bioaerosol-related diseases, respectively. The results indicated apparent differences between PM- and bioaerosol-associated DMs at five different time points and revealed dynamic alterations in the urinary metabolic profiles of young healthy humans with cyclic exposure to clean and polluted air environments. Our findings will help in investigating the detrimental health effects of short-term coexposure to airborne PM and bioaerosols in a real-time manner and improve clinically predictive or diagnostic strategies for preventing air pollution-related diseases.