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[Display omitted] • The manuscript has five highlights as following below: • A novel PGS was fabricated by a cutting-reorganizing method. • The IP reaction of AGQDs and TMC could only grow in the 2D interface. • PGS showed a willow-leaf-like shape with a typical 2D porous structure. • The membrane were prepared by in-situ sealing technology with PA for the first time. • The PGS/PA composite membrane successfully overcame the "trade-off" effect. In this study, we proposed a novel interfacial polymerization (IP) method for porous graphene-based sheets (PGS) with 2D structure by recombining of amino graphene quantum dots (AGQDs) at the two phases interface, and then a large-area ultrathin composite films with excellent permeability and high selectivity were prepared by in-situ sealing technology with polyamide (PA) for the first time. Adjusting the pH of AGQDs solution could promote and regulate the formation of PGS with a lamella diameter of 2 μm, an ultrathin thickness of 3.2 nm and pore size of 2.71 nm, which showed a willow-leaf-like shape with a typical 2D porous structure. Then, the PGS at the interface was sealed in-situ by PA layer generated by injecting piperazine (PIP) in the IP process to form PGS/PA composite membrane. When the PGS synthesis time and PIP concentration were reached to 60 s and 0.02 w/v% respectively, the prepared PGS/PA composite membrane exhibited the best comprehensive properties, with an ultrathin thickness of 18.6 nm, super hydrophilic surface, excellent stability and strong alkali resistance. At this condition, the permeation flux of PGS/PA composite membrane could reach 28.4 L·m−2·h−1·bar−1, which was over 300% of the original PA composite membrane (9.1 L·m−2·h−1·bar−1), while the rejection of Congo red was maintained more than 99.4%, which successfully overcame the "trade-off" effect. [ABSTRACT FROM AUTHOR]

• Continuous, underwater superelastic, durable PNAs with rime-mimetic structure was fabricated. • PNAs exhibit ultrahigh POP loading of 83 wt%, resulting in efficient uptake of micropollutants. • Well-designed interfacial interactions contribute to the stability and elasticity of PNAs. • HSP theory is adopted to guide the selection of the optimal elution solvent. Developing nanofibrous aerogels with high surface area, nanoscale porosity, and robust underwater stability has been considered as one of the most promising strategies for designing the next-generation of high-efficiency extraction media, yet still facing great challenges. Herein, we report a size rearrangement of porous organic polymers (POPs) into superelastic rime-mimetic structured aerogels based on bacterial cellulose nanofibers (BCNs)-assisted interfacial engineering strategy. This strategy facilitates micro-interlocking between POP and BCN, significantly enhancing the attaching strength of POP particles at the POP/BCN interface. Thus, the optimized aerogels (PNAs) exhibit excellent underwater elasticity and compression fatigue resistance (∼0% plastic deformation after 500 compression cycles), as well as high BET surface area (305.44 m2/g) and hierarchical porosity (containing micro/meso/macropores), mainly due to the ultrahigh loading of POP particles (83.33 wt%). Given the possession of the abovementioned features and the careful selection of elution solvents guided by Hansen solubility parameter theory, PNAs exhibit a superior micropollutant adsorption capability (∼250 mg/g) and elution efficiency (concentrate sample volume by 50 times). The successful preparation of such material could inspire the development of next-generation hierarchically porous nanofibrous aerogel-based extraction media for water treatment. [ABSTRACT FROM AUTHOR]

[Display omitted] • Electrocatalytic NB reduction is a mild and green route to obtain high-purity AN. • Composition control and morphology engineering viably upgrade the electrocatalyst. • CuNiAl with intermetallic compound displays conspicuous conversion and AN selectivity. • Nanoporous structure enlarges the specific surface and also facilitates the kinetics. • High efficiency for producing AN is achieved via inhibiting HER at low overpotential. Electrocatalytic nitrobenzene (NB) hydrogenation with high selectivity, yield and Faradaic efficiency (FE) is an economic and sustainable approach to produce high-purity aniline (BA). However, its implementation is essentially hindered by state-of-the-art Cu-based metallic electrocatalysts, which are of insufficient intrinsic activity and unstable nanostructures, in addition to low FE caused by irrepressibly competitive hydrogen evolution reaction at high overpotential. Herein, we report a self-supported nanoporous CuNiAl alloy as a highly efficient electrocatalyst towards NB hydrogenation reaction. Owing to the incorporation of Ni in intermetallic Al 4 Cu 9 (Ni), which is of high intrinsic activity, and the hierarchical nanoporous architecture, which facilitates electron transfer and mass transportation along interconnective metal ligaments and interpenetrative pore channels, self-supported nanoporous CuNiAl electrode exhibits remarkably enhanced NB hydrogenation electrocatalysis for BA product with high selectivity (98%), yield (88.5%) and FE (82.3%) at ultralow operating potential (−0.07 V versus RHE). This nanoporous CuNiAl alloy outperforms some of the best Cu-based nanocatalysts reported previously. This work makes a stride for designing novel low-cost electrocatalysts for high-efficient NB hydrogenation by following composition control and morphology engineering. [ABSTRACT FROM AUTHOR]

• A series of fluorine/sulfur-comodulated COF are designed and synthesized. • DFT calculation verifies the enhanced affinity to sulfur species and electronic conductivity of COF. • The TpF-1S cathode exhibits high specific capacity and superb cycle stability. Sulfur-based LIBs (S-LIBs) are expected to stand out to replace conventional lithium ion batteries as candidate for sustainable high-density energy storage. However, the main obstacles to the practical application of S-LIBs are the easy dissolution of lithium polysulfides (Li 2 S x) intermediates, as well as the poor electrical conductivity of sulfur species and transport of charge carriers. To achieve high-capacity and long-lifespan S-LIBs, rational design and construction of cathode materials as hosts for Li 2 S x species with simultaneously strong bonding and high electric/ionic conductivity are essential but very challenging. Herein, according to the density functional theory (DFT) prediction, a series of sulfurized covalent organic frameworks (COFs) are synthesized by the nucleophilic aromatic substitution reaction (SNAr). Benefiting from the chemical confinement to Li 2 S x by synergistic carbonyl groups and strong C-S chains, the S-LIBs based on the optimized TpF-1S delivers a high specific capacity of 1377 mAh/g and remains 1150 mAh/g after 1000 cycles at 2 C with ∼100% Coulombic efficiency. The S-LIBs also achieves an energy density up to 2000 Wh/kg, which is approaching 78% of the theoretical value and four times over the commercial lithium-ion batteries. This work paves the way for exploiting a new generation of ultrastable sulfur hosts for high-density S-LIBs. [ABSTRACT FROM AUTHOR]

High-performance aqueous ammonium ion microbatteries are constructed based on amorphous/crystalline dual-phase layered metal oxides. [Display omitted] • Amorphous/crystalline dual-phase (NH 4) x V 2 O 5 anode is synthesized by electrodepositing. • The preintercalated NH 4 + ions act as pillars to retain the large interlayer spacing. • The V-Mn based aqueous ammonium ion battery has a voltage window of 1.6 V. The prosperity of microelectronic systems stimulates fast development of high-performance power sources with micro/nano sizes. Considering the defects of conventional lithium-ion microbatteries, i.e. high cost, severe safety concerns as well as the unsatisfactory power delivery due to the sluggish ion transport of the organic electrolytes, novel energy storage microdevices are worth looking forward to. Here, we assemble an aqueous ammonium-ion microbattery using 2D (NH 4) x V 2 O 5 with amorphous/crystalline dual-phase nanostructure deposits on 3D nanoporous Au as anode while nanoporous Au/δ-MnO 2 composite as cathode. As a result of the superb electronic/ionic conductivities as well as the large voltage window, the resultant NP Au/ ac -(NH 4) x V 2 O 5 //NP Au/δ-MnO 2 aqueous ammonium-ion microbattery exhibits ultrahigh energy density of 0.126 Wh cm−3 with electrical powers ∼280-fold higher than commercial lithium thin-film batteries, in addition to excellent rate capability (∼84.2% capacity retention at 5–50 mV s−1 scan rates) and cycling stability (retains ∼93.3% of the initial value after 10,000 cycles at 500 mV s−1). The superb performance endows it to be promising candidate as monolithic micropower source for micro/nano portable/wearable electronics with high energy storage and power delivery demands. [ABSTRACT FROM AUTHOR]

[Display omitted] Six β-keto-enamine-based covalent organic frameworks (COFs) with different backbones and substituents have been successfully prepared, and their structure–property relationships of these COFs were systematically revealed. • Six β-keto-enamine COFs with different backbones and substituents were prepared. • The structure–property relationships of the COFs have been systematically studied. • TpPa-Cl 2 has the best area-normalised photocatalytic activity. • Its hydrogen production rate is about 11.73 µmol⋅m−2⋅h−1 per 0.01 g catalysts. Covalent organic frameworks (COFs), as new promising photocatalysts, have aroused great interests, but the systematic study on the structure–property relationship of COF-photocatalysts is scarcely reported. Herein, six β-keto-enamine-based COFs with different backbones and substituents have been prepared. Through systematic experiments and DFT calculation, the structure–property relationships of the composition, structure and substituents of COFs on their spectra, specific surface area, hydrophobicity, electronic structures, carrier separation and photocatalytic hydrogen production have been studied. We explore that the backbone of COFs has important influence on their band gap, spectral absorption and carrier separation. While the substituents affect the band positions, surface area and hydrophobicity of COFs. Comprehensively, TpPa-Cl 2 (constructed by 1,3,5-triformylphloroglucinol and 2,5-dichloro-1,4-phenylenediamine) exhibits the best area-normalised photocatalytic performance for hydrogen production, which is about 11.73 µmol·m−2·h−1 (0.01 g catalysts) with apparent quantum efficiency of 17% at 400 nm. This work provides a new perspective for the rational design and construction of efficient COF-photocatalysts. [ABSTRACT FROM AUTHOR]