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Nanoplastics (NPs) have raised global concern owing to their potential health effects. Herein, after simulated and natural solar irradiation, polyethylene, polypropylene, polystyrene, and poly(vinyl chloride) nanoplastics (PVC NPs) were observed to exhibit enhanced fluorescence, particularly PVC NPs. Furthermore, the role of photoaged NPs as a potential fluorescence indicator was evaluated by exposing a model aquatic organism Daphnia magna to these NPs. Our results revealed that photoaged NPs exhibited strong fluorescence owing to the generation of conjugated π bonds, which can achieve π-π* electron transition with low energy consumption. Photogenerated fluorescence also enabled the photoaged NPs to act as efficient fluorescent tracers, which can help track NP migration in various organisms. The results of two-photon laser confocal scanning microscopy revealed that the photoaged NPs could translocate across biological barriers and accumulate in extraintestinal tissues in addition to being ingested and excreted. Moreover, compared with pristine NPs, the photoaged NPs underwent biodegradation more easily, probably because of increased hydrophilicity due to photogenerated oxygen-containing moieties. Therefore, in addition to producing fluorescent NPs without the attachment of external fluorescent dyes, the natural photoaging process can promote the migration and degradation of photoaged NPs in food chains.

Nano-enabled foliar-application could be an ideal strategy for advancing agricultural productivity. However, it remains largely unknown whether they inhibit or promote the uptake of pollutants. Here, we systematically examined how foliar applying SiO 2 nanoparticles (nSiO 2 ) and ZnO nanoparticles (nZnO) (20 nm, 100 mg·L -1 ), influence polycyclic aromatic hydrocarbons (PAHs) uptake in 4-week-old amaranth (Amaranthus tricolor L.). Results showed that foliar application of nSiO 2 or nZnO enhanced amaranth biomass by 20.2-26.4% but decreased PAHs bioaccumulation in leaves by 20.4-54.9% after 7-d incubation. Changes regarding amino acid-related pathways (alanine/aspartate/glutamate metabolism and arginine biosynthesis) and energy maintenance pathways (TCA cycle) were observed in amaranth leaves after foliar application of nSiO 2 and nZnO. Specific PLS-DA analyses with total PAHs uptake as the biological endpoint showed that the contents of PAHs positively correlated with valine (R 2 = 0.799) and tyrosine (R 2 = 0.789), but negatively correlated with D-tagatose (R 2 = 0.805) and L-gulonolactone (R 2 = 0.877), indicating greater oxidant stress under higher PAHs level. We propose that mechanisms of declined uptake of PAHs involve the biomass-dependent dilute effect and activation of biological response against PAHs accumulation. These findings provide a prospective vision on how nano-enabled foliar-application alleviates PAH-enriched environmental burden while producing higher-yield agricultural products, especially for low toxic and biocompatible nSiO 2 ., Competing Interests: Declaration of competing interest The authors declare no conflict of interest., (Copyright © 2022 Elsevier B.V. All rights reserved.)

Phthalic acid eaters (PAEs) play the role of plasticizer and have been widely used in the industrial and plastic production process. But due to not chemically bound in the polymeric matrix, PAEs can be easily released directly and/or indirectly into the environment, and pose a threat the ecosystem and human health. Small-molecule self-assembled nanoparticles have drawn more and more attention due to advantages of precise molecular structure, biocompatibility, great diversity, and tunability in optical properties and functionalities. Here we report the use of disaggregation-induced emission (DIE) based supramolecular assembly to design organic nanoprobe for detection PAEs. In the water solution, the designed small organic fluorophore AJ-1 was aggregated via noncovalent forces to form fluorescence off nanoparticles, but in the presence of PAEs, they disaggregated and produced a clear light-up fluorescent signal. The detection of PAEs with selectivity, sensitivity and rapid response were further achieved. The experiment of recovery of PAEs in real-water sample illustrated the practicability of probe AJ-1 in real-world applications. Besides, cellular uptake assay suggested that AJ-1 could pass through membrane and gather in the cytoplasm., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2021 Elsevier B.V. All rights reserved.)

Nano-Fe 2 O 3 embedded in montmorillonite particles (Fe-Mt) were prepared to degrade diethyl phthalate (DEP) with citric acid (CA) under xenon light irradiation. Compared to pristine montmorillonite (Na-Mt), the embedding process increased 14.5-fold of iron content and 1.8-fold of specific surface area. The synthesized Fe-Mt have more oxygen vacancies than Fe 2 O 3 nanoparticles (nFe 2 O 3 ), which could induce more reactive oxygen species (ROSs) generation in the presence of CA under xenon lamp irradiation. Fe-Mt with CA enhanced photo-assisted degradation of DEP 2.5 times as compared to nFe 2 O 3 with CA. Quenching experiments, electron paramagnetic resonance (EPR) spectroscopy and identification of products confirmed that surface-bound •OH was the main radical to degrade DEP. Common anions (i.e., NO 3 - , CO 3 2- , Cl - ) and humic acid could compete •OH with DEP and cause slower degradation of DEP. The removal efficiency of DEP was more than 56% with Fe-Mt after three recycles, and the dissolved Fe concentration from Fe-Mt was below 75 μmol/L, indicating Fe-Mt had a good stability as a catalyst. Fe-Mt together with CA appeared to be a promising strategy to remove organic pollutants in surface water, or topsoil under solar irradiation., (Copyright © 2020. Published by Elsevier B.V.)

Monodispersed hollow mesoporous silica nanoparticles (HMSNs) are successfully synthesized via a facile dual template method, in which poly(styrene-co-methyl methacrylate-co-methacrylic acid) (PS-PMMA-PMAA) particles are used as hard template for producing the hollow structure and cetyltrimethylammonium bromide (CTAB) used for introducing the mesopores in the silica shells. The obtained HMSNs possess uniform diameter and morphology, and the shell of which could be adjusted by changing the addition of silicon precursor. The synthesized HMSNs have been characterized by transmission electron microscopy (TEM) and nitrogen physisorption. Furthermore, the HMSNs are used as support for in-situ deposition of silver nanoparticles (Ag NPs) using n-butylamine as reducing agent for AgNO3 in ethanol. Significantly, Ag NPs were successfully supported in the HMSNs without any aggregation. The Ag-deposited HMSNs showed excellent dispersibility in ethanol and water, and their antibacterial activity against Escherichia coli (E. coli) ATCC 25922 and Staphylococcus aureus (S. aureus) ATCC 6538 have been demonstrated. Therefore, the unique nanostructure based on the HMSNs provided a useful platform for the fabrication of antibacterial agent with superior activity and accessibility. And also, it is expected to be a significant template for the synthesis of other novel nanostructures., (Copyright © 2016 Elsevier Inc. All rights reserved.)

Biogenic twinning β-phase anhydrous guanine nanoplatelets are utilized as optical materials in organisms. However, it is still a puzzle how to produce crystalline guanine platelets in aqueous solutions since guanine has a low solubility in water. Herein, the controlled synthesis of twinning guanine nanoplatelets was realized for the first time in an aqueous solution in the presence of poly(1-vinylpyrrolidone-co-vinyl-acetate) via ammonia volatilization. The synthesized rectangular twinning guanine nanoplatelets with an exposed (100) face were β-form anhydrous guanine (β-AG), and the twinning angle of the two c-axes was about 83°, similar to the biogenic twinning β-AG nanoplatelets. The length and thickness of the twinning β-AG nanoplatelets were about 2 μm and 42 ± 3 nm, respectively. There were about five to seven layers observed for the synthesized twinning β-AG nanoplatelets, with each layer being as thin as 6 ± 2 nm. It was proposed that amorphous guanine particles are formed as intermediate precursors, which dissolve and recrystallize to single-crystalline β-AG nanoplatelets, and then multilayered twinning β-AG nanoplatelets are formed via π–π interaction with the assistance of the guanine-quartet assembly. The obtained twinning β-AG exhibited a high reflection intensity in the visible and near infrared region and a brilliant pearlescent luster, indicating that they could potentially be applied as optical materials. This work provides a new design strategy to synthesize particular organic molecular crystals with low solubility in water and a novel formation mechanism for twinning organic crystals. [ABSTRACT FROM AUTHOR]

A hierarchical porous zeolite Y (HPZY) supported Ni–Co catalyst was prepared by pyrolyzing nickel tetracarbonyl and using modified deposition-precipitation to highly disperse Ni–Co nanoparticles onto HPZY. Hecaogou subbituminous coal was effectively ethanolyzed to obtain ethanol-soluble portion (ESP E) in a high yield (21.2%). Sequentially, ESP E was subjected to the deep hydroconversion (DHC) over prepared Ni 10% -Co 3% /HPZY at 150 °C under 4 MPa of initial hydrogen pressure for 24 h in n -heptane to produce deeply hydroconverted ethanol-soluble portion (ESP DHC). All the group components in ESP E , including arenes (53.3%), oxygen-containing organic compounds (24.4%), and nitrogen-containing aromatics (2.3%) were completely converted to chain alkanes (CAs, 36.8%), cyclanes (39.2%), and hydroarenes (24.0%). In addition, the hydroisomerization of CAs and hydroreforming of aromatic rings (ARs) in ESP DHC are predominant over Ni 10% -Co 3% /HPZY with more accessibility of active sites under mild conditions. Ni 10% -Co 3% /HPZY with suitable acidity and highly dispersed Ni–Co nanoparticles can effectively activate H 2 to H⋯H and further heterogeneously split H⋯H to H+ and H−. H⋯H and H+ transfer plays crucial roles in the DHC of ESP E. Correspondingly, the related mechanisms are evidenced by the DHC of 2,2′-oxydinaphthalene (ODN) over Ni–Co/HPZY. Ni 10% -Co 3% /HPZY maintains high activity for the DHC of ODN under mild conditions after 4 recycles. • Modify CZY by fluorine-alkaline cascaded treatment to obtain HPZY. • Ni–Co/HPZY has an outstanding catalytic activity and stability for the DHC of ESP E. • Ni–Co/HPZY effectively induced the formation of H+, H−, and H⋯H during the DHC. • All of group components in ESP E were completely converted to CAs, cyclanes, and HAsII. [ABSTRACT FROM AUTHOR]

Monoclinic Li TiO phase is prepared from Li CO and TiO mixtures by using a high-energy ball milling method, combined with subsequent calcinations at low temperature. Pure phase Li TiO nanopowders with the average particle size of 36.8 nm are obtained from the precursor milled for 20 h and calcined at 500°C for 5 h, i.e., 300°C lower than required by a conventional solid state reaction process or chemical routes. It is suggested that high-energy ball-milling method is a simple and practical route to synthesize Li TiO nanopowders. [ABSTRACT FROM AUTHOR]

Human proximal renal tubular epithelial cells (HK-2) are constantly exposed to glyco-oxidative injury due to the diabetic nephropathy. It has been reported that nanoparticles (NPs) due to their unique properties may show outstanding antioxidant activity. The influences of high glucose (HG) treatment with a concentration of 50 mM on HK-2 cells toxicity and the protective effects of synthesized gold NPs (AuNPs) by hydrothermal method were explored in terms of free radical production and advanced glycation end products (AGEs) formation. Also, the expression of Bax, Bcl-2, Caspase-3 at both mRNA and protein levels was evaluated by qPCR and ELISA assays, respectively followed by SIRT3 and SOD2 activity assays. It was observed that AuNPs with a diameter of about 30 nm and good colloidal stability at physiological pH attenuates HG‐induced cytotoxicity in HK-2 cells through a significant increase in cell viability and the reduction of free radical production, AGEs formation, and expression of Bax/Bcl-2 and Caspase-3 at both mRNA and protein levels. However, 3-TYP, a SIRT3 inhibitor, significantly inhibited the inhibitory effects of AuNPs on HG‐induced cytotoxicity. This data revealed that HG concentrations induced glyco-oxidative stress in kidney cells and AuNPs could be used as promising candidates in reducing the risk of progression of diabetic nephropathy. [ABSTRACT FROM AUTHOR]

• FeOOH particles is in-situ grown on physically-exfoliated graphene nanosheets. • GN@FeOOH hybrid exhibits enhanced active area and electron transfer kinetics. • A novel and highly sensitive H 2 O 2 electrochemical sensing platform is developed. • Facile strategy for the synthesis of graphene-based hierarchical structures. Compared with extensively-used chemically-exfoliated graphene, physically-exfoliated graphene-based heterogeneous structures are rarely used for electrochemical analysis. In this work, physically-exfoliated graphene nanosheets (GN) are used as the substrate material to couple high-activity FeOOH nanoparticles. Multiple characterization technology confirm that a novel hierarchical hybrid composed of physically-exfoliated graphene nanosheets and FeOOH nanoparticles (GN@FeOOH) is easily obtained by a facile solution growth strategy. Plenty of fiber-like FeOOH nanoparticles with size about 20 nm are uniformly anchored on the surface of graphene with robust adhesion. Relative to pristine GN, the electrochemical active area and electron transfer kinetics are greatly boosted for the introduction of high-activity of FeOOH nanoparticles. Benefiting from the remarkably enhanced electrochemical activity, the obtained GN@FeOOH hybrids exhibit excellent electrochemical performance toward the reduction of H 2 O 2. As a result, a novel and rapid electrochemical sensing platform for the detection of H 2 O 2 at low applied potential (-0.25 V vs. SCE) is fabricated with wide linear range (0.25 μM - 1.2 mM) and high sensitivity (265.7 μA mM−1 cm-2), and the limit of detection is as low as 0.08 μM, which is comparable with many other noble metal-based electrochemical sensors and exceeds many non-noble metal-based electrochemical sensors. [ABSTRACT FROM AUTHOR]

Transition metal sulfides as ideal oxygen reduction reaction (ORR) catalysts have great potential to regulate multiple reaction pathways and understand their corresponding internal reaction mechanisms at cathode in zinc-air batteries (ZABS), effectively. This work adopted a facile one-pot synthesis method based on chemical vapor deposition (CVD), which utilizes the synergistic effect of zeolite imidazolium ester skeleton (ZIF-8) and polypyrrole (PPY) to grow nitrogen-sulfur co-doped carbon nanotubes (NS-CNT) in the shape of colonic with a relatively uniform size and encapsulated with FeS nanoparticles as the main active sites. The synthesized purpose catalyst noted as FeS-NS-CNT-900, in which that the FeS nanoparticles were tightly encapsulated in carbon nanotubes, and this special structure ensures that the FeS particles do not detach during the reaction, thus greatly enhancing their electrochemical activity and stability. As expected, the FeS-NS-CNT-900 catalyst exhibited a half-wave potential of 0.877 V which is higher than that of commercial platinum charcoal (0.847 V), at 0.1 mol KOH. More importantly, the formation of abundant FeS catalytic active sites, the optimal conditions for NS-CNT growth, and the covered mechanisms of the enhanced ORR reaction activity of FeS-NS-CNT-900 were thoroughly investigated. Additionally, whileFeS-NS-CNT-900 was used as an air cathode material for the assembly of a zinc-air battery, it exhibited a peak power density and specific capacity of 123 mW cm−2 and 785.81 mA h g−1, respectively, which were significantly better than that of platinum-carbon cathode (92.8 mW cm−2 and 740.4 mA h g−1). And surprisingly, the battery with FeS-NS-CNT-900 cathode exhibited (delivered/showed) a high cycle stability of 260 h at 5 mA cm−2. Conclusively, present work provides a feasible method for in situ growth of sulfur and nitrogen co-doped carbon nanotube encapsulated transition metal sulfide nanoparticle catalysts, which may pave a new avenue for the preparation of high ORR performance air cathode material for ZABS. [Display omitted] • In situ-grown nitrogen-sulfur co-doped carbon nanotubes encapsulating FeS nanoparticle catalysts. • Growth of NS-CNTs originates from the synergistic interaction of ZIF-8 with PPY. • The precise control of CNT growth enables the regulation of catalyst performance. • The synergistic interaction of FeS with NS-CNTs is essential for the promotion of ORR response. [ABSTRACT FROM AUTHOR]

The issue of organic-inorganic perovskites has received considerable attention because of its importance in improving the efficiency of solar cells. The power conversion efficiency of solar cells has climbed from 3.8% in 2009 to over 25.2% currently. Its outstanding performance is mainly attributed to its long carrier lifetime (101−2 ns), diffusion length (μ m), high absorption coefficient, direct bandgap (band gap ~1.55 eV), stable electron/hole migration and other characteristics. In addition to these features, organic-inorganic lead perovskites also have high fluorescence yields and tunable absorption wavelengths, making it an ideal laser gain medium. In this paper, the physical vapor deposition (PVD) is used to grow atomically smooth lead iodide nanoplatelets (PbI 2 NPL) on a mica substrate, and convert the PbI 2 NPL into atomically smooth single-crystal perovskite nanoplatelets (CH 3 NH 3 PbI 3 NPL) by chemical vapor deposition. The nanoplatelets can naturally form WGM (whispering-gallery-mode) microcavities. We can control the size of CH 3 NH 3 PbI 3 NPL (from a few microns to dozens of microns) by adjusting the deposition location, deposition temperature, and deposition time. With the increase of edge length, the mode interval decreases, the peak is red shift, and it shows excellent lasing characteristics with a threshold down to 17 μ J/cm2. This has great application potential in the field of low-cost chip light source. • The size-controlled (15 μm-88 μm) perovskite nanoplatelets were prepared by the vapor phase deposition method. • We realized room-temperature WGM lasing with a threshold down to 17 μJ/cm2 and a Q factor up to 1396. • The large-size perovskite nanoplatelets generated smaller mode spacing and red shift of the wave peaks. [ABSTRACT FROM AUTHOR]

Exploring cost-effective non-noble metal-based catalysts with high activity and stability is of great significance for energy conversion and storage involving oxygen evolution reaction (OER). Here, we employed a laser irradiation technique to synthesis Fe doped CoO nanoparticles with ultrafine size (≈ 5.4 nm) and abundant oxygen vacancies (Fe-O v -CoO). The ultrafine size of Fe-O v -CoO nanoparticles provides more active sites to be exposed. Fe doping and oxygen vacancy promote the intrinsic activity and electron transfer rates of Fe-O v -CoO, giving rise to high activity and stability catalyst for OER. Fe-O v -CoO delivers a large current density of 1000 mA cm−2 at an overpotential of 548 mV, which is much better than commercial RuO 2. Moreover, Fe-O v -CoO presents a remarkable long-term stability with negligible degeneration at a high current density of 500 mA cm−2 for 120 h. This work provides a new route to develop OER electrocatalyst with high activity and stability. [ABSTRACT FROM AUTHOR]

Metal oxide engineered nanomaterials (ENMs) offer a range of opportunities for sustainable agriculture. Despite ENMs acting as vectors of nutrients to plants, it remains unclear whether they promote the uptake of contaminants, such as polycyclic aromatic hydrocarbons (PAHs), by plants. The present work revealed that ENMs (SiO 2 nanoparticles, nSiO 2 ; CeO 2 nanoparticles, nCeO 2 ; 100 mg L−1) significantly enhanced the accumulation of Pyr by 18.4–34.8% in soybean (Glycine max L.) tissues over 15-d hydroponic cultivation. Metabolomics analyses suggested the metabolic disturbance occurred in both Pyr-only exposure (910.3 ± 87.6 mg kg−1 Pyr) and the co-exposure of Pyr and ENMs (804.5 ± 52.1 – 1226.6 ± 12.0 mg kg−1 Pyr). In addition, higher Pyr contents induced more notable reprogramming of multiple metabolic processes in soybean, such as C/N cycle. Further statistical analyses indicated that more than 70% metabolic permutations were induced by Pyr, which was more profound than ENMs. The results in this study highlight the potential risks and specific molecular mechanisms of emergent ENMs if co-exposure with ubiquitous PAHs. This study also promotes further research into the responsible and sustainable development of nanotechnology in the agriculture. [Display omitted] • nSiO 2 and nCeO 2 significantly increased Pyr contents in soybean by 18.4–34.8%. • Smaller sized nSiO 2 increased the most Pyr accumulation in soybean. • Higher Pyr content enhanced reprogramming of C/N cycle in soybean tissues. • Compared to ENMs, Pyr contributed more to metabolism disturbances. [ABSTRACT FROM AUTHOR]

[Display omitted] • FeS 2 nanoparticles were wrapped by BrGO shell. • 50 mg•L-1 BPA can be efficiently removed within 20 min at pH 3–9 with FeS 2 @BrGO. • Persistent free radicals and reductive sulfur in FeS 2 @BrGO could efficiently reduce Fe(III) to Fe(II) • The complexation between Fe(III) and surface O-containing groups decreased the redox potential of Fe(III)/Fe(II) • The utilization efficiency of H 2 O 2 was greatly improved at neutral pH with FeS 2 @BrGO. To prevent metal catalysts from agglomeration and leaching, encapsulating metal nanoparticles in carbon shells has attracted much attention in electro-Fenton (EF) processes. However, most of the carbon–metal catalysts were suffering from slow regeneration of Fe2+ due to the unavailable redox reactions at electrode surface, which hindered the EF efficiency. Here, we report a novel boron doped graphene (BrGO) wrapped FeS 2 nanocomposite (FeS 2 @BrGO), which exhibits extremely high catalytic performance due to the synthetic interaction between BrGO and FeS 2 , as well as the efficient regeneration of Fe(II). The EF system with FeS 2 @BrGO could completely remove 50 mg L-1 bisphenol A within 20 min under neutral pH. EPR results suggest the existing of abundant persistent free radicals and reductive sulfur could directly donate electron to Fe(III). The electrochemical measurements further demonstrated the decreased reduction potential of Fe(III)/Fe(II) by the coordination between Fe(III) and surface oxygen-containing functional groups. Reactive organic radicals also played an important role in reducing Fe(III) to Fe(II). These findings provide a new strategy for hybrid catalysts combining graphene shells with metal sulfide, which has great potential in wastewater treatment. [ABSTRACT FROM AUTHOR]