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• VN/Mo 2 C heterointerfaces nanoparticles are monodispersed on N-doped carbon nanosheets. • Mo 2 C and VN synergistically promote the diffusion and conversion of polysulfides. • The functional separator also has excellent protective effect on the lithium anode. • The modified separator exhibits superb electrochemical performance in Li-S batteries. Lithium-sulfur (Li-S) battery is deemed as one of the optimal next-generation energy storage devices due to its low cost and high energy density. However, the shuttle effect of lithium polysulfide (LiPS), sluggish reaction kinetics, and fatal Li-dendrite growth hinder its practical applications. In this work, a bifunctional nitrogen-doped carbon nanosheet conductive framework embedded with VN-Mo 2 C heterointerfaces (VN/Mo 2 C@CNS) is reported as a separator modifier for both sulfur cathode and lithium anode. The VN/Mo 2 C@CNS can offer a synergistic effect of strong surface affinity, good catalytic activity, and small diffusion barrier to accelerate the conversion of polysulfides, which was confirmed by in-situ Raman and theoretical calculation. Moreover, the composite has good lithiophilicity, thus inhibiting the formation of dendrites and achieving uniform lithium deposition. Benefiting from the above merits, the Li-S cells with VN/Mo 2 C@CNS separator obtain desirable rate performance (687 mAh g−1 at 4 C), long cycle life of 1000 cycles (0.042 % capacity attenuation per cycle at 1 C), high areal capacity of 4.2 mAh cm−2 (under a high sulfur loading of 5.6 mg cm−2), and stable performance in protecting the Li anode (at 5 mA cm−2 for 1000 h). This work highlights a novel strategy for facilely designing heterostructures, offering valuable insights to tackle sulfur cathode and lithium anode challenges simultaneously for longevous Li-S batteries. [ABSTRACT FROM AUTHOR]

[Display omitted] • A mild pressure-assisted hydrothermal pretreatment was developed to facilitate PHK. • Air pressure of 3 MPa improved hemicelluloses removal more than heating up 10 °C. • Pressurised PHK facilitated the reduction of active alkali content in Kraft process. • This strategy could provide superior cellulose properties and purity. The efficient removal of hemicelluloses while preventing cellulose hydrolysis is crucial in Kraft pulping yet remains challenging. Herein, a mild pressure-assisted hydrothermal pretreatment strategy was developed in this study prior to Kraft pulping. Research indicated that pretreatment at 155 °C under 3 MPa pressure significantly enhances hemicelluloses removal (to 70.63 %), surpassing even that at 165 °C under ambient pressure. Moreover, during pre-hydrolysis Kraft pulping, pressure-assisted hydrothermal pretreatment could reduce the concentration of active alkali used in the subsequent pulping process. The cellulose properties (viscosity = 491 ml/g) and purity (R10 = 94.60 %) of bleached pulp obtained from pressure-assisted hydrothermal pretreatment outperform those obtained from conventional hydrolysis. Furthermore, the removed hemicelluloses were converted into monosaccharides and polysaccharides to produce high-value chemicals in downstream processes. Therefore, pressure-assisted hydrothermal pretreatment not only enhanced hemicelluloses removal and pulp properties but also reduced alkali concentration in the subsequent pulping process, promoting sustainable development in pulp production. [ABSTRACT FROM AUTHOR]

Graphical abstract Highlights • Gallic acid significantly mobilized Sb from goethite with increasing pH. • Sb(III) oxidation and the competitive adsorption inhibited Sb adsorption. • Self-generated H 2 O 2 and quinone species accounted for Sb(III) oxidation. • The edge-sharing inner-sphere complexes were formed between Sb and goethite. Abstract Natural organic matter (NOM) profoundly influences the metal(loid)s immobilization by iron (Fe) minerals, which, in turn, are the host phase for Sb that control its mobilization and bioavailability. However, the potential effect of the redox-active phenolic acids derived from NOM on this process has rarely been explored. Therefore, the adsorption of Sb(III) on goethite and Sb(III) oxidation in the presence of a common phenolic acid—gallic acid (GA)—was systematically investigated. The reaction mechanisms were unraveled by the combination of wet chemistry, electron paramagnetic resonance (EPR), X-ray photoelectron spectroscopy (XPS), and X-ray absorption fine structure (XAFS) spectroscopy. Our results showed the addition of GA significantly inhibited Sb adsorption on goethite as the pH increased. Except for the competitive adsorption by GA, the inhibition also resulted from the extensive Sb(III) oxidation in the suspension and the lower Sb(V) sorption capacity of goethite at higher pH. The alkaline condition facilitated the generation of reactive oxygen species (hydrogen peroxide) and quinone species (semiquinone radical (SQ −) and oxidized GA), accounting for the significant Sb(III) oxidation in the solution and on the goethite surface. Besides, the edge-sharing inner-sphere complexes were formed between Sb and goethite regardless of the presence of GA. Our findings demonstrated the remarkable role of the phenolic groups in NOM on the adsorption of Sb(III) on goethite. [ABSTRACT FROM AUTHOR]

[Display omitted] • UiO-66-SO 3 H/Fe(1:1)-800 exhibited high tetracycline degradation efficiency. • The influence of operating parameters on tetracycline degradation was analyzed. • It exhibited good stability and potential for wastewater treatment applications. • Mechanism of TC degradation by heterogeneous electro-Fenton process was proposed. Designing efficient heterogeneous electro-Fenton (HEF) catalysts for in-situ H 2 O 2 generation and organic pollutant degradation in water has become a hot research topic. In this study, a series of novel UiO-66-SO 3 H/Fe(x)-800 materials were successfully prepared by carbonizing sulfonic acid metal-organic frameworks (UiO-66-SO 3 H) doped with iron for tetracycline (TC) HEF degradation. The catalytic performance of UiO-66-SO 3 H/Fe(x)-800 was evaluated by comparing different HEF systems, and the effects of different operating parameters and co-existing substances were investigated. The results indicated that UiO-66-SO 3 H/Fe(1:1)-800 displayed excellent performance for TC degradation over a broad pH range, with an optimal TC degradation efficiency of 90.10% in 90 min and a low energy consumption of 4.39 kWh/kg/TOC. Furthermore, the superior stability and reusability of this catalyst were proved in continuous cycling experiments with low iron leaching (<1.000 ug/L). The mechanism exploration demonstrated that TC was mainly oxidized by ‧OH and 1O 2. In addition, iron-doped porous carbon carrier improved the utilization rate of H 2 O 2 and accelerated the regeneration of Fe2+, which played an important role in the HEF process. The HEF system based on UiO-66-SO 3 H/Fe(1:1)-800 also exhibited satisfactory performance when treating actual water samples, presenting broad application prospects. [ABSTRACT FROM AUTHOR]

Manganese (Mn) oxides have high Cd(II) sorption affinities and could effectively immobilize Cd(II) in soil and aquatic systems. However, coexisting Fe(II) can react with Mn oxides at oxic-suboxic interfaces, thereby affecting Cd(II) immobilization by Mn oxides. Mn(IV)-rich Mn oxides in the environment are readily to be reduced to Mn(III)-rich Mn oxides by natural organic matter. Herein, we determined the effects of Fe(II) on Cd(II) immobilization by Mn(III)-rich δ-MnO 2 (denoted as HE-MnO 2 ) at pH 5.5 and 7.5. Results show that Fe(II) decreased Cd(II) retention on HE-MnO 2 at pH 5.5 but had no effects at pH 7.5 due to the high Cd(II) adsorption affinity of HE-MnO 2 at high pH. Poorly crystalline Fe oxides, likely ferrihydrite, uniformly precipitated on HE-MnO 2 surfaces upon Fe(II) addition at both pHs. β-MnOOH formed at the high initial Fe(II) concentration at pH 7.5. Cd(II) was mainly adsorbed on HE-MnO 2 rather than the newly formed Fe oxides and β-MnOOH which had low Cd(II) adsorption capacities. The decrease of Cd(II) sorption in the presence of Fe(II) could be explained by the reduction of HE-MnO 2 , the precipitation of Fe oxides on HE-MnO 2 , and the competition of generated Mn(II) for the sorption sites. Cd(II) formed double-corner sharing (DCS) and double-edge sharing (DES) complexes with Mn(III) edge sites on HE-MnO 2 . After the addition of Fe(II), Cd(II) formed only DCS complexes with Mn(III) edge sites. The alternation of the surface complexes caused by Fe(II) promoted Cd(II) desorption from HE-MnO 2 . This work suggests that Fe(II) can decrease the removal efficiency of Cd(II) by Mn(III)-rich δ-MnO 2 at oxic-suboxic interfaces in the environment. [ABSTRACT FROM AUTHOR]

[Display omitted] • Quasi-2D Dion-Jacobson (DJ) tin halide perovskites intercalated by alkyl ligands exhibit significantly improved stability. • The calculated features of Sn-vacancy further confirm the improved stability and depressed trapping states of (PDA)Cs 2 Sn 3 I 10. • The (PDA)Cs 2 Sn 3 I 10 perovskites exhibit optimal bandgaps and improved charge transportation. • The significantly improved phase stability and conductivity have been verified by experimental results. Currently, the development of CsSnI 3 perovskite is still greatly hindered by their intrinsic deficiencies, such as their easy phase transformation. To address this issue, we theoretically constructed Dion-Jacobson (DJ) perovskites intercalated by divalent 1,5-pentamethylenediamine (PeDA2+) exhibit significantly enhanced phase stability. However, the carrier mobility is always depressed owing to the charge localization and severe lattice distortion in the presence of spacers among wafers. Thus, the alkyl ligand cations (e.g. , ethylenediamine (EDA), 1,3-propanediamine (PDA), 1,4-butanediamine (BDA)) with varying lengths as organic intercalators are examined for optimizing charge transfer. Compared with the other configures, the (PDA)Cs 2 Sn 3 I 10 exhibits the most significantly improved stability due to the enhanced chemical bonding and faintest structural distortions, as evidenced by computed the formation enthalpy. Formation energy and transition level of tin-vacancy defect further confirm the improved stability and depressed defect-trapping states. Meanwhile, 2D-(PDA)Cs 2 Sn 3 I 10 exhibit obviously increased electrical conductivity and reduced carrier effective masses, which might benefit the photoelectric conversion of solar cells. [ABSTRACT FROM AUTHOR]

Manganese (Mn) oxide is considered as a potential regulator of the fate of many contaminants in soil due to its abundance and reactivity. The present study investigated the oxidation and sorption mechanisms of antimony (Sb) on δ-MnO 2 , by combining batch equilibrium experiments, kinetic experiments and various spectroscopic techniques. The collective results confirmed the high Sb(III)-oxidizing capacity of Mn(IV) sites on δ-MnO 2 and the oxidation reaction was proton-driven. However, the oxidation process was gradually inhibited by the accumulation of manganese antimonate precipitates, the production of less reactive Mn(III), and the site-blocking effects of products Mn(II) and Sb(V) on the surface. Different from the direct sorption of Sb(V) by δ-MnO 2 , the oxidation of Sb(III) destroyed the surface structure of δ-MnO 2 and exposed more reactive sites as evidenced by X-ray powder diffraction (XRD) and transmission electron microscopy (TEM). The stronger Sb(V) sorption along with the oxidation of Sb(III), therefore, could be attributed to several binding modes, i.e., Mn(II) cation bridge, precipitation with Mn(II), along with inner-sphere complexations with surface Mn(IV) and Mn(III) sites. Sb(V) was sorbed at the edge sites of δ-MnO 2 forming monodentate mononuclear complex with a configuration of Mn-O(H)-Sb(V) as confirmed by supplementary X-ray photoelectron spectroscopy (XPS), X-ray absorption fine structure (EXAFS) spectroscopy and attenuated total reflectance Fourier transform infrared (ATR-FTIR) spectroscopy techniques. The findings altogether help to contribute to a better understanding on the geochemical dynamics of Sb with δ-MnO 2 in subsurface environment. [ABSTRACT FROM AUTHOR]

[Display omitted] • Citric acid-assisted ultrasmall monodisperse CeO 2 nanoparticles (NPs) are prepared. • They are firstly used for efficient photocatalytic degradation of glyphosate. • 2.1 nm CeO 2 NPs remove glyphosate in 5 and 20 min under UV and visible irradiation. • The possible photocatalytic mechanism is proposed by the detailed experiment study. Degradation of glyphosate has attracted much attention all over the world, since glyphosate has been demonstrated to affect the human health through the accumulation in food chain. Herein, we use citric acid as capping agent to synthesize highly-stable aqueous dispersions of monodispersed CeO 2 nanoparticles (NPs) with ultrasmall controllable size of 2.1–4.8 nm, high surface areas and rich oxygen defects, which were firstly used as photocatalyst for efficient degradation of glyphosate. The obtained CeO 2 NPs display a significantly size-dependent catalytic activity and a good stability performance. Ultrasmall 2.1 nm CeO 2 NPs have 6 times (UV) and 20 times (visible light) degradation rates of 4.8 nm counterpart, which can rapidly remove glyphosate from water at pH = 4 in 5 min (UV) and 20 min (visible light). And the related degradation kinetics data at pH = 4 are well related to the pseudo-first-order kinetic model. In this highly-efficient photocatalytic degradation process, the grafted citric acid can initiate the electron transfer to accelerate the regeneration of Ce3+ sites as electron donors and enhance photocatalytic performance via ligand-to-metal charge transfer. This work provides a new method to prepare high-performance CeO 2 photo-nanocatalysts for the removal of glyphosate and emphasizes the important role of modifier, oxygen defects and particle size in seeking efficient photocatalytic materials. [ABSTRACT FROM AUTHOR]

The porous THB functionalized UiO-66-NH 2 MMMs have been successfully synthesized via electrospinning. The prepared MMMs possesses the superior acid/alkaline resistance, durableness, stability and cyclicity owing to strong π-π interaction of THB, U6N and TPU. And its maximum adsorption capacity for Ga(III) is 96.18 mg g−1, which is higher than UiO-66-NH 2 and reported adsorbents. [Display omitted] • Porous MOF-based MMMs with excellent stability was fabricated by strong π-π interaction. • MMMs retains excellent stability after soaked in 5 mol L-1 HCl 7 days or after 9 cycles. • It has high water flux (greater than300 L m-2h−1) and rejection of Ga(III) after 12 h working. • It has better adsorption capacity (96.18 mg g−1) and selectivity than other sorbents. Reported powdery adsorbents with poor adsorption efficiency and stability make it imperative to develop novel materials to extract gallium ions (Ga(III)) from effluents. Herein, UiO-66-NH 2 -based mixed matrix membranes (TPU/0.1THB/U6N-1.5 MMMs) via electrospinning is firstly reported for separation and recovery of Ga(III). TPU/0.1THB/U6N-1.5 MMMs efficiently overcomes multiple bottlenecks of powder UiO-66-NH 2 , including poor stability, reusability and adsorption capacity. Its maximum adsorption for Ga(III) is 96.18 mg·g−1 at pH 10.0. It has superiority in selective adsorption of Ga(III) from Al(III), Cu(II), Zn(II), Co(II) coexistence solution. Adsorption capacity of TPU/0.1THB/U6N-1.5 for Ga(III) reaches more than 80% after 9 cycles. Specially, it still retains excellent mechanical strength, flexibility and structural integrity after 12 h filtration, or after 9 adsorption-desorption cycles, even soaked in 5 mol·L-1 HCl for a week. TPU/0.1THB/U6N-1.5 MMMs also improves the problem of low water flux. TPU/0.1THB/U6N-1.5 with high MOFs loading possess high water flux of 382.2 L·m−2·h−1 with a permance of 382.2 L·m−2·h−1·bar−1 and rejection rates of 90% for Ga(III). The main adsorption mechanism of TPU/0.1THB/U6N-1.5 is based on the chelation between phenolic hydroxyl groups of MMMs and Ga(III) at pH 10.0. Overall, the as-prepared TPU/0.1THB/U6N-1.5 has potential for water treatment through the process of membrane adsorption. [ABSTRACT FROM AUTHOR]

[Display omitted] • Cationized lignin was prepared rapidly and efficiently from industrial lignin. • Enhancing the water solubility and antimicrobial properties of industrial lignin. • Biodegradable lignin-based antimicrobial nanofiber membranes were prepared. • Lignin-based NFMs exhibited outstanding breathability and anti-UV properties. • NFMs had excellent antimicrobial performance (100%) against E. coli and S. aureus. Industrial lignin is underutilized as an abundant natural aromatic resource, resulting in a serious waste of biomass resources. In this study, a strategy was developed to efficiently achieve cationization of industrial lignin, which not only could increase the water solubility of the industrial lignin for good compatibility with polyvinyl alcohol (PVA), but also incorporated quaternary ammonium groups to improve the antimicrobial performance. The results showed that the cationized lignin products could be obtained by reacting at 75 °C for only 20 min and had good compatibility with PVA in aqueous systems, which not only shortened the lignin cationization time, but also reduced the amount of cationization reagent. By integrating the electrospinning technique, the nanofiber membranes with excellent antimicrobial performance can be produced for the field of medical dressing. With the addition of 7 wt% of the cationized lignin, the novel developed antimicrobial nano-medical dressing exhibited excellent breathability (61.08 mm/s), anti-UV properties, and compatibility with portable spinning technique. In addition, the cationized lignin-based nanofiber membranes had excellent antimicrobial performance, with an antimicrobial ratio of 100 % (Gram-positive Staphylococcus aureus and Gram-negative Escherichia coli), as well as being biodegradable. In conclusion, this strategy could realize the cationization modification of industrial lignin while expanding the application in medical dressings and improving the economic sustainability of biorefinery strategies. [ABSTRACT FROM AUTHOR]

[Display omitted] • Novel chain extenders bearing multiple sulfonate groups are synthesized. • These extenders lead to the local aggregation of ionic groups. • Much lower dose of chain extenders is needed for effective emulsification of WPU. • The water resistence property of WPU is thus greatly improved. The anionic chain extenders used in waterborne polyurethane (WPU) generally contain one anionic ion per extender. Increasing its content in WPU makes the WPU emulsion more stable, however also makes the WPU film more water sensitive, which is a dilemma needed to be solved. Herein, a novel class of anionic chain extenders bearing two or four sulfonate groups is rationally designed. The ion strength of chain extender is thus enhanced and the distribution of ionic charges on the resulting WPU is also altered. The relationship between the structure of the chain extenders and the properties of WPU is studied systematically. The results show that the critical percentage of the anionic extender needed to for stable WPU emulsion is reduced in a nonproportional way with the increase of the number of anionic groups per extender. For example, while the critical percentage of the chain extender for stable emulsion formation for aliphatic-type chain extender containing two sulfonates is 6 mol%, that for chain extender containing four sulfonates is only 2 mol%. Hence the overall hydrophilic segments on the WPU backbone is greatly decreased, which make the WPU more water resistant without sacrificing the emulsification capability of WPU. Among them, the threshold to form stable emulsion for WPU made from the ether-type chain extender containing four sulfonates is as low as 1.2 mol%, and the water absorption of the resultant film is only 3.5 %. The resulting WPU films show strong adhesion to various surfances and excellent resistance toward abrasion. This provides a new strategy to balance the emulsification capability and water-resistence property of WPU. [ABSTRACT FROM AUTHOR]

[Display omitted] • Tailored one-pot DES pretreatment was developed for fractionation of biomass. • The excellent delignification (96.5%) was achieved by ultrafast DES pretreatment. • The glucose yield of the substrate reached to 95.4% under mild enzymatic hydrolysis. • Lignin nanoparticles obtained had excellent morphology and antioxidant activity. • Recycled DES had distinguished pretreatment performance and cyclic stability. To achieve the global bio-based recycling economy with lignocellulosic biomass as feedstock, the additional value must be gained from both carbohydrates and lignin. In this study, a tailored one-pot lignocellulose fractionation, which was driven by ultrafast and recyclable microwave-assisted ternary deep eutectic solvent (DES, choline chloride: ethylene glycol: AlCl 3) pretreatment, was developed to significantly reduce the natural "biomass recalcitrance", promoting the production of lignin nanoparticles and facilitating enzymatic saccharification of cellulose. Confocal Raman microscopy (CRM) was applied to visually monitor the delignification in different cell walls during the DES pretreatments. Under the optimal condition (110 °C, 10 min), the glucose yield of the pretreated poplar via enzymatic saccharification reached 95.4 %, which was 5.8 times higher than that of the control. Advanced NMR characterizations of the DES lignin and control lignin fractions demonstrated that lignin polymers in the poplar wood had undergone the following structural changes, such as dehydration, depolymerization, condensation, and modification. Results showed that the regenerated DES lignin were nano-sized lignin, exhibiting the low molecular weights, narrow distribution (1.28

[Display omitted] • The construction of hollow Fe 3 O 4 /Ag composite particles is templated with soluble NaCl. • The particles can reflect electromagnetic waves multiple times with their cavity structure. • The Fe 3 O 4 /Ag epoxy composite film achieves a −62.37 dB reflection loss with a 4.80 GHz effective absorption band. • The particles exhibit 99.84 % photocatalytic degradation of dye in 30 min, maintaining 96.62 % over 6 cycles. Hollow metallic composite particles are widely used in microwave absorption and catalysis due to their unique cavity structures, and favorable physical and electromagnetic properties. In this work, we propose an approach to prepare highly dispersed Fe 3 O 4 /Ag composite particles with a hollow structure using water-soluble green template method combined with in-situ growth process. The as-prepared cubic Fe 3 O 4 /Ag composite particles with an average size of 3.19 μm of hollow Ag and 11.65 nm of Fe 3 O 4 coating on the surface were used as fillers for preparing microwave absorption epoxy resin films, showing a minimum reflection loss of −62.37 dB at 16.63 GHz with 7.5 mm thickness. An effective absorption bandwidth of 4.80 GHz can be observed in the frequency bands of 4.70–6.09 and 14.59–18.00 GHz. This mechanism is attributed to the internal cavity of the Fe 3 O 4 /Ag particles realizing multiple reflections of electromagnetic waves, and the synergistic effect of Fe 3 O 4 and Ag. Moreover, this perspective is confirmed by their photocatalytic performance. The Fe 3 O 4 /Ag particles achieve a high photocatalytic degradation efficiency of 99.84% for Congo red dye within 30 min of light exposure and maintain a value of 96.62% after 6 cycles, demonstrating an outstanding reusability. [ABSTRACT FROM AUTHOR]

Highlights: [•] K-Fe/Ni used to simultaneously remove Cu (II) and nitrate. [•] The increase in the degradation of nitrate in the presence of Cu (II). [•] Characterization by SEM, EDS, XRD and XPS. [•] Formation of trimetallic K-Fe/Ni/Cu nanoparticles. [ABSTRACT FROM AUTHOR]

Abstract: As a major pollutant flue gas, nitric oxide (NO) emission has received great attention of the world. Various technologies have been developed to reduce NO emission. Among them, wet scrubbing approach seems to be promising concept. Ferrous chelate solution has been demonstrated as a suitable and efficient option in flue gas denitrification process due to its high reaction rate with NO and good regeneration ability. However, NO absorption rate is strongly affected by mass transfer limitation of NO and FeII(EDTA) solution in traditional reactors. In this study, RPB is firstly introduced as a gas–liquid reactor to enhance the NO removal efficiency by FeII(EDTA) solution. Preliminary experimental results are presented on the absorption of NO by investigating the effects of operating parameters on NO removal efficiency in RPB. The removal efficiency peaks when the pH value of the absorbent reaches 7. The optimum temperature for this gas–liquid absorption system is in the range of 293–303K. When the gravity level of the RPB is higher than 150g, the removal efficiency could reach 87%. In addition, the NO removal efficiency decreases with the increase of the gas–liquid ratio. The simultaneous increase of the gas and the liquid flow rates has no obvious effect on the removal efficiency. The obtained results imply a great potential of RPB in the removal of NO from flue gases. [Copyright &y& Elsevier]

• Sb 2 S 3 NRs with high carrier transport were prepared by a novel epitaxial growth. • Novel Tm3+ doped strategy weakens the Fermi level pinning effect of Sb 2 S 3. • The enhanced PEC performance is attributed to the S-scheme mechanism. • The injection efficiency of the optimized photocathode was 81.7%. With the advantages of high absorption coefficient, non-toxicity and low cost, Sb 2 S 3 shows great potential as a narrow bandgap photocathode in the field of PEC hydrogen production. However, the separation and transportation of photogenerated carriers in the reported Sb 2 S 3 photocathode are inefficient due to its anisotropy and the Fermi level being pinned by deep-level defects. Therefore, Tm3+ doped Sb 2 S 3 nanorods with the selective carrier transport orientation were epitaxially grown on SnSe 2 film by a simple hydrothermal strategy to modulate the defect property of Sb 2 S 3 , optimize carrier transportation and separation efficiency, and improve the PEC performance of photoelectrodes. Experimental results showed that the doping of Tm3+ weakening the Fermi level pinning while achieving the conversion of Sb 2 S 3 to n-type conducting property. The S-scheme heterojunction formed by Tm3+ doped Sb 2 S 3 nanorods labeled as Sb 2 S 3 : Tm3+ and SnSe 2 nanosheets provided a stronger driving force to optimize carrier interface transportation. The photocurrent density (−0.91 mA cm−2) is increased about 18 times compared to the pristine Sb 2 S 3 photocathode. This work developed an effective doping strategy to weaken the Fermi level pinning and provided a novel idea for the epitaxial growth of Sb 2 S 3 nanorods to optimize the carrier transportation. [ABSTRACT FROM AUTHOR]

• Monodisperse ZrO 2 nanocrystals were controllably prepared by a phase-transfer route. • The as-prepared ZrO 2 nanocrystals have tunable shapes, crystal forms and sizes. • DFT calculation was used to study the root causes of underpinning growth mechanisms. • Fluorescent monodispersed ZrO 2 :Yb3+/Er3+ nanocrystals could be similarly prepared. Colloidal nanocrystals can offer exquisite control of physical and chemical properties for technological applications by tuning their sizes, shapes and crystal forms. Herein, a convenient phase-transfer route was presented to controllably prepare transparent dispersions of monodispersed ZrO 2 nanocrystals in an aqueous-organic two-phase medium. By adjusting the surfactants, solvents and basicity, the controllability of crystal forms from monoclinic to tetragonal phases, the particle length from 5 to 20 nm, and the different shapes including spindle, cobblestone, sphere, branch, rod and cube can be achieved. The as-prepared ZrO 2 nanocrystals can be readily dispersed in nonpolar solvents, thereby forming the ultra-highly concentrated (60 wt%), highly stable (>18 months) and highly transparent nanodispersions. Density functional theory (DFT) calculations were further used to elucidate the root causes of underpinning growth mechanisms. This work not merely enriches the methodology of controllable fabrication of monodispersed sub-10 nm ZrO 2 nanocrystals, but also enables a platform to synthesize rare-earth-doped nanophosphors using ZrO 2 as the host matrix. The fluorescent ZrO 2 :Yb3+/Er3+ nanocrystals, which can be easily monodispersed in organic solvents, were also prepared with visible luminescene properties under near-infrared irradiation. [ABSTRACT FROM AUTHOR]

• Size-tunable monodisperse Pd nanocrystals were prepared in a rotating packed bed. • They were adopted as pseudohomogeneous catalyst for nitrobenzene (NB) reduction. • 2.6 nm Pd nanocrystals displayed excellent catalytic property and good stability. • The obtained catalytic kinetics data confirm to the Langmuir-Hinshelwood model well. • DFT calculation was used to study the adsorption of NB on the surface of catalyst. Nitrobenzene (NB) reduction is an important catalytic reaction, which is commonly performed in aqueous medium mainly with heterogeneous catalysts. In this work, highly stable aqueous nanodispersions of Pd nanocrystals with a tunable average size between 2 and 11 nm are conveniently prepared in a high-gravity rotating packed bed (RPB) reactor, and firstly serve as a pseudohomogeneous catalyst for NB reduction. As compared to a conventional stirred tank reactor (STR), the product prepared in the RPB reactor has a more uniform particle size. More importantly, the reaction time can be greatly shortened from 3 min (STR) to 1 s (RPB), thereby realizing a continuous preparation. This Pd pseudohomogeneous catalyst displays a significantly size-dependent catalytic activity and a good stability performance. Ultra-small 2.6 nm Pd nanocrystals have a reaction rate five times as fast as 10.1 nm counterpart. The obtained kinetics data confirm to the Langmuir-Hinshelwood model well, having a small error of <10%. Furthermore, the adsorption behavior of NB molecules on the surface of Pd nanocrystals was also studied with density functional theory (DFT) calculation. Since the processing capacity of the used lab-scale RPB reached 44.2 g/h, this route may offer a general platform for mass production of monodisperse nanocrystals as pseudohomogeneous catalyst for highly efficient catalysis. [ABSTRACT FROM AUTHOR]

Graphical abstract Highlights • Low molecular weight phenolic acids induced the rapid Sb(III) oxidation. • SQ − and ROS were formed in low molecular weight phenolic acid solutions. • Increasing pH facilitated Sb(III) oxidation. • Low bond dissociation enthalpy of phenolic OH indicated the fast Sb(III) oxidation. Abstract Quinone-like moieties are active components of natural organic matter (NOM), whose redox reactions may exert substantial influence on the behavior of trace metals in natural waters. The interactions between NOM and antimony (Sb) influence the mobility and toxicity of Sb, but the mechanism of this process is poorly understood. In this study, batch oxidation experiments were conducted to evaluate the effects of model quinone-like moieties, i.e., 1,4-hydroquinone and low molecular weight phenolic acids (LMWPAs), including gallic acid, caffeic acid, and protocatechuic acid, on the oxidation of Sb(III) in the absence of light. The results indicated that Sb(III) was rapidly oxidized to Sb(V) in the presence of different phenolic acids in neutral and alkaline conditions. The oxidative reactions were pH dependent and the Sb(III) oxidation rate constant (k obs) increased by one or two orders of magnitude when the pH shifted from 7.0 to 9.0. The combination of electron paramagnetic resonance and free radical quenching studies elucidated that reactive oxygen species (hydrogen peroxide) and quinone species (the semiquinone radical and oxidized forms of LMWPAs) were the main contributors to the Sb(III) oxidation. According to density functional theory based calculations, the bond dissociation enthalpy of the phenolic hydroxyl group is well correlated with k obs , which is in line with its pro-oxidant property towards Sb(III) through the production of semiquinone radical. The findings of this study provided new insights into the mechanism of the oxidation of Sb(III) by NOM. [ABSTRACT FROM AUTHOR]

The aim of this study was to quantify the removal of halogenated pollutants (using triclosan as a model pollutant) from aqueous solution by zero-valent iron coupled with a weak magnetic field. We determined the removal efficiency of triclosan from a sodium sulfate solution at different pH values under both aerobic and anaerobic conditions. The removal of triclosan followed pseudo-first-order kinetics in both the presence and absence of a weak magnetic field. The calculated rate constants indicated higher removal efficiencies of triclosan under the aerobic condition compared to the anaerobic condition. In addition, increase of triclosan removal from acidic solutions was achieved with the assistance of weak magnetic field. X-ray diffraction and X-ray photoelectron spectroscopy analysis indicated that FeO(OH) and Fe 3 O 4 were the main aerobic transformation products, suggesting that the zero-valent iron surfaces were completely oxidized. The aerobic and anaerobic transformation products of triclosan were analyzed by liquid chromatography tandem mass spectrometry. The results indicated that the application of a weak magnetic field could be an efficient and cheap treatment process to improve the removal of halogenated pollutants by zero-valent iron, which may be developed for future use. [ABSTRACT FROM AUTHOR]

We demonstrate the controllable conduction band-edge reconfiguration in quasi-2D Dion-Jacobson α-CsPbI 3 perovskites enabled by dimensional engineering based on the rationally designed organic dipole moments and inorganic layer numbers, which endows the perovskites with fundamentally enhanced electron-hole separation toward efficient photovoltaic applications. [Display omitted] • The discovery of CB-edge reconfiguration in quasi-2D CsPbI 3 perovskites. • The achievement on controllable CB-edge reconfiguration. • The encouraged separation and in-plane transport of charge carriers. Generally, the band-edge configurations of ABX 3 perovskite (where A is MA+/FA+/Cs+ cation, B represents Pb2+ or Sn2+, and X is halogen, respectively) are constructed by the electronic states of B and X ions, implying that A-site cation has no significant contribution to the band edge. In current work, through first-principles calculation, we report the controllable conduction band (CB) edge reconfiguration of quasi-2D Dion-Jacobson α -CsPbI 3 perovskites enabled by dimensional engineering for making A-site cations affect perovskite CB edge, which is based on rationally designed organic chain length (m) of A-site organic spacer cations and inorganic layer numbers (n). It is discovered that the energy level of organic CB would be moved up with the increase of m , and that of inorganic CB would be shifted down with the raise of n , allowing the dimensional engineering of quasi-2D perovskites with controllable CB-edge configuration. Consequently, the achieved CB-edge reconfiguration could endow the quasi-2D perovskites with encouraged carrier separation and in-plane transfer. The discovery of CB-edge reconfiguration in quasi-2D perovskites by dimensional engineering, which is highly meaningful to direct the exploration of advanced perovskites for efficient solar cells. [ABSTRACT FROM AUTHOR]

[Display omitted] • Controllable growth of high-quality PNCs in polymer films with aqueous route were achieved. • The PL QY of the as-fabricated films can be optimized to 95.3% by adding the HBr and OABr additives. • High-performance WLEDs with a wide gamut can be assembled by the as-prepared green and red films. Perovskite nanocrystals (PNCs)@polymer films are one of the exciting candidates for fabricating high-definition display devices, owing to their universal merits such as high efficiency, superior color purity, and tunable emissions. However, the existed techniques are always based on organic solvents, of which the inevitable toxicity greatly limits their scalable applications. Herein, we report a facile strategy based on a distinctively different aqueous route for in-situ growth of MAPbBr 3 (MA = CH 3 NH 3 +) PNCs in polyvinyl alcohol (PVA) matrix, enabling the environmentally-friendly and large-scale production of high-photoluminescence (PL) PNCs@polymer films. It is discovered that rapid evaporation of solvents in the precursor film is the key to separated crystallization of polymer and PNCs, thus allowing the controllable fabrication of high-quality PNCs@PVA films with tunable emissions. As a proof of concept, the as-fabricated MAPbBr 3 PNCs@PVA film with typical size of 90 mm × 90 mm exhibits high transmissivity and uniformity, with a strong green emission and PL quantum yield (QY) of 95.3%. Accordingly, by using the resultant green and red films, a white light-emitting device (WLED) sized 35 mm × 40 mm is assembled, which delivers a wide color gamut (121% of NTSC standard), underscoring their very promising applications in modern display devices. [ABSTRACT FROM AUTHOR]

Highlights: [•] Pt–graphene/TiO2 nanocomposites were synthesized by MAS method. [•] Pt–graphene/TiO2 nanocomposites were used for the degradation of organic Dye under UV/Visible light. [•] Enhanced photocatalytic activity was observed for Pt–graphene/TiO2 nanocomposites. [•] Red shift observed having band gap of 1.8eV in the nanocomposite from (DRS) analysis. [ABSTRACT FROM AUTHOR]

[Display omitted] • Two sulfides exhibit high adsorption capacities and ultrafast removal of Eu3+. • Selective Eu3+ adsorption against interfering ions in natural water. • Lanthanides recovery from acidic industrial wastewaters is realized. • The adsorption mechanism is ion exchange between Eu3+ and cations. • The soft Lewis basic and flexible layer is beneficial to selective Eu3+ uptake. Efficient and selective capture of lanthanides from radioactive wastewater containing excessive diverse concentrated salts is challenging but urgently demanded for environmental protection and human health. Herein, we present an effective approach for Eu3+ uptake from complex aqueous solutions by using two layered sulfide adsorbents (Me 2 NH 2) 2 (Ga 2 Sb 2 S 7)·H 2 O (FJSM-GAS-1) and (Et 2 NH 2) 2 (Ga 2 Sb 2 S 7)·H 2 O (FJSM-GAS-2). Both adsorbents exhibit ultrafast kinetics (within 2 min) and high absorption capacities for Eu3+ (127.7 and 115.8 mg/g for FJSM-GAS-1 and FJSM-GAS-2 , respectively). The distribution coefficient (K d) can be as high as 6.39 × 105 and 6.00 × 105 mL/g for FJSM-GAS-1 and FJSM-GAS-2 , respectively, exceeding that of reported Eu3+ adsorbents. They still display high selectivity for Eu3+ in presence of excessive competitive cations (e.g., Na+ and K+). Particularly, high K d values remain for Eu3+ removal from Eu3+-contaminated tap, lake and sea water, and lanthanides recovery from acidic industrial wastewater. Absorbed Eu3+ ions can be facilely eluted using a low-cost method. The adsorption mechanism, illuminated via DFT calculations coupled with characterizations of EA, Raman, XPS and EXAFS, is ion exchange between Eu3+ and interlayered cations owing to the strong interactions between Eu3+ and framework S2−. This work confirms that layered sulfides are promising adsorbents for efficient removal of lanthanides/actinides from wastewater for environmental remediation. [ABSTRACT FROM AUTHOR]

[Display omitted] • A sustainable EXA process is proposed for total valorization of corncob. • All lignocellulose components are valorized with the carbon utilization of 79.6%. • The overall revenue of the EXA biorefinery process reached 1414.55 USD. • GHG intensities shows a much lower GHG emissions intensity per USD. Lignocellulose, as the most abundant type of inedible biomass, is considered as a promising renewable feedstock for making fuels, chemicals, and materials. However, its complex structure makes most of current biorefinery processes suffer from low resource utilization rates, high energy consumption or ill-defined market orientation of the obtained products. Here, we propose and evaluate the EXA (Ethanol, Xylose, Adhesive) biorefinery strategy based on current xylose industry. This process integrates four conversion and separation stages to consecutively produce ethanol, xylose, and adhesive with total carbon utilization of 79.6%. The key innovation is the establishment of an easy-to-operate process for direct production of high-quality adhesive from a lignin-rich liquid fraction that makes the overall process significantly more sustainable. Techno-economic analysis (TEA) shows that the revenue of proposed EXA process increases more than 110 times compares with the current process and life cycle assessment (LCA) demonstrates a much lower CO 2 footprint from an environmental burden per unit of revenue perspective. [ABSTRACT FROM AUTHOR]

• Highly stable monodispersed sulfur nanoparticles with a size of 15–50 nm. • Controllable preparation using a microfluidic anti-solvent precipitation method. • Efficient and continuous synthesis in both Y-type and T-type microchannels. • CFD simulation to verify the mixing process. • Modified sulfur nanoparticles with good antibacterial properties. Sulfur nanoparticles (SNPs) have been frequently used for sterilization due to their high biocompatibility and environmental friendliness. Compared with traditional sublimed sulfur, SNPs have some superior properties, such as the smaller particle size, better dispersibility in water and even higher antibacterial performance. Therefore, the objective of this study is to prepare SNPs with a controllable particle size and uniform morphology using a microfluidic anti-solvent precipitation method, whose process is continuous and ideal for large-scale production. The SNPs with a range of 15–50 nm can be prepared in both a Y-type microchannel (YMC) and T-type microchannel (TMC). Interestingly, for the SNP preparation process, the YMC shows a better mixing effect than TMC, which has been verified by the CFD simulation. Compared with a traditional batch stirred tank (ST), these two microchannels can not only guarantee a relatively small and uniform particle size, but also reduce the solvent consumption by at least 50%. More importantly, the SNPs show a better continuous bactericidal ability for Staphylococcus aureus (S. aureus) and Escherichia coli (E. coli), compared with traditional micro-sized sublimed sulfur. The SNPs together with surfactant CTAB have a synergistic effect, which can enhance their antibacterial activities. Especially, among all the control groups, the as-prepared 15 nm SNPs have a better bactericidal performance, which can reduce the S. aureus colony number from ∼ 8 log CFU/mL to below the detection limit in 15 h, and reduce the colony number of E. coli from ∼ 8 to 1.8 log CFU/mL. [ABSTRACT FROM AUTHOR]

• High-gravity technology was used to intensify anionic polymerization. • Novel reactor was used to polymerize n -butyl cyanoacrylate. • Rotating packed bed has special rules about the effect of operating conditions. • Polymers with various molecular weight has different in vitro characteristics. Poly (n -butyl cyanoacrylate) (PBCA) nanoparticles are widely used as biocompatible and bio-erosive materials in a range of biomedical applications, especially for drug delivery systems. This paper reports a novel synthesis method of PBCA nanoparticles with high productivities and purities in a rotating packed bed. The particle size and molecular weight of PBCA nanoparticles were controlled by adjusting the high-gravity factor, surfactant concentration, pH, temperature and monomer concentration. The high-gravity factor shows an obvious influence on the particle sizes, while it has few effects on molecular weight. The surfactant concentration and pH also affect molecular weight and particle sizes. Moreover, compared with conventional stirred tank, the reaction time of RPB procedure was dramatically reduced from 12 h to 2 h, and the purity of products increased from about 93% to 96%. Furthermore, when the molecular weight of PBCA increased, the in vitro cytotoxicity to Hep G2 cells firstly increased and then decreased, and the cellular uptake was improved. In summary, PBCA with controllable molecular weight and particle sizes can be synthesized using a facile high-gravity method. [ABSTRACT FROM AUTHOR]