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[Display omitted] • A highly efficient MOF adsorbent for Carbon Capture and Storage (CCS). • Micro-/mesoporous MOF-74(Ni) was prepared by a facile condensation reflux approach. • MOF-74(Ni) morphology, crystal size, and isosteric heat for CO 2 adsorption can be easily tuned. • Appreciable CO 2 removal and decent selectivity of MOF-74(Ni)-24-140 due to its abundantly exposed metal sites, conducive isosteric heat, and micropore channels. Though the highest CO 2 capture capacity belongs to liquid amine-solutions, solid matters capable of CO 2 capture are also highly sought, providing that, they offer at least analogous CO 2 adsorption capacity and CO 2 /N 2 selectivity. Herein, a surprisingly high-performance Ni-based metal–organic framework for CO 2 adsorption, namely MOF-74(Ni), was synthesized by a facile condensation reflux approach. It was found that the structure and CO 2 adsorption isosteric heat of MOF-74(Ni) could tune upon varying the synthesis duration under various temperatures. The optimized MOF-74(Ni)-24-140 (synthesized at 140 °C for 24 h) displays outstanding CO 2 adsorption capacity of 8.29/6.61 mmol/g at 273/298 K under normal pressure of 1.0 bar, several times higher than previously reported MOF-74-Ni (2.0/2.1 times), UTSA-16 (1.5/1.6 times), and DA-CMP-1 (3.6/4.9 times) under similar conditions. The excellent CO 2 capture capacity is associated to the abundant adsorption sites (mainly arising from the cationic Ni2+ ions) and narrow micropore channels (mainly arising from the cage structure of Ni2+ ions coordinated with organic linkers). Offering a high CO 2 selectivity (CO 2 /N 2 = 49) and a well-tuned isosteric heat of CO 2 adsorption (27–52 kJ/mol) besides its decent CO 2 capture capacity, MOF-74(Ni) strongly stands out as an efficient and strong CO 2 capturing material with industrial scale applicability. [ABSTRACT FROM AUTHOR]

[Display omitted] • CoMoO@Co composite catalyst was successfully grown on graphite felt. • Metallic Co nanosheets drive amorphous to crystalline conversion in Co-Mo oxides. • The fabricated catalyst acts as a robust bifunctional electrocatalyst for the oxidation of water and urea. • The nanoflowers structure provides abundant and largely accessible catalytic active sites. • The coupling interface formed between metallic Co and Co-Mo oxides facilitates electron transfer in catalytic reaction. Oxygen evolution reaction (OER) and urea oxidation reaction (UOR) play important roles in the field of hydrogen energy preparation and pollution treatment. In this work, by merging bimetallic Co-Mo oxides with metallic Co on the graphite felt (GF), we effectively manufacture a 3D bifunctional and highly efficient electrocatalyst (CoMoO@Co/GF) with multi-site functionality for the simultaneous reduction of water and the oxidation of urea in an alkaline medium. The presence of metallic Co causes Co-Mo oxides to evolve from amorphous to crystalline structures. The coupling interface produced between metallic Co and Co-Mo oxides is proven to facilitate electron transport in addition to extensively accessible and highly electroactive Co-Mo oxide nanoflower architecture. The experimental results reveal that the overpotentials for OER and UOR in the CoMoO@Co/GF electrode require only 269 and 115 mV to obtain a current density of 10 mA cm−2, respectively. Furthermore, with the aid of urea, the overpotential for HER at the current density of 10 mA cm−2 is lowered to 155 mV. Most notably, the constructed CoMoO@Co/GF-based electrolytic cell only requires a 1.5 V dry battery to achieve effective H 2 evolution and noteworthy stability, outperforming the commercial catalyst-based device and many previous results. The combination of experiments and theoretical calculations further clarifies the active sites in the catalyst. What's more, the pathway of electron transfer in the catalytic process is defined. [ABSTRACT FROM AUTHOR]

[Display omitted] • A novel Fe-TiO 2-x /TiO 2 S-scheme homojunction was constructed. • The Fe-TiO 2-x /TiO 2 exhibits optimized CO/CH 4 generation rates of 122/22 μmol g-1h−1. • The role of OV and Fe in improving catalytic performance has been discussed. • The photocatalytic mechanism was detailedly analyzed. CO 2 -to-high value-added chemicals via a photocatalytic route is of interest but strangled by the low efficiency. Herein, a novel Fe-TiO 2-x /TiO 2 S-scheme homojunction was designed and constructed by using a facile surface modification approach whereby oxygen vacancy (OV) and Fe introducing on the TiO 2 nanorod surface. The as-synthesized Fe-TiO 2-x /TiO 2 S-scheme homojunction exhibits positive properties on promoting photocatalytic CO 2 reduction: i) the nanorod structure provides numerous active sites and a radical charge transfer path; ii) the doped Fe and OV not only synergistically enhance light utilization but also promote CO 2 adsorption; iii) the Fe-TiO 2-x /TiO 2 S-scheme homojunction benefits photoexcited charge separation and retains stronger redox capacity. Thanks to those good characters, the Fe-TiO 2-x /TiO 2 homojunction exhibits superior CO 2 reduction performances with optimized CO/CH 4 generation rates of 122/22 μmol g-1h−1 which exceed those of pure TiO 2 by more than 9.4/7.3 folds and most currently reported catalytic systems. This manuscript develops a facile and universal approach to synthesize well-defined homojunction and may inspire the construction of other more high-efficiency photocatalysts toward CO 2 reduction and beyond. [ABSTRACT FROM AUTHOR]

Graphical abstract Abstract Spontaneous solar-driven water splitting to generate H 2 with no pollution discharge is an ideal H 2 generation approach. However, its efficiency remains far from real application owing to the poor light-harvesting and ultrafast charge recombination of photocatalysts. To address these issues, herein, we employed a novel but simple chemical bath deposition (CBD) method to construct CdS/SrTiO 3 nanodots-on-nanocubes at room temperature (ca. 25 °C). The as-synthesized nanohybrids not only expand light absorption from ultraviolet (UV) to visible light but also significantly retard charge recombination owing to the well-defined heterostructure formation. As a result, the CdS/SrTiO 3 exhibits high photocatalytic performance with H 2 evolution rate of 1322 μmol g−1 h−1, which is 2.8 and 12.2 times higher than that of pristine CdS and SrTiO 3 , respectively. This work provides a universal approach for the heterostructure construction, and inspired by this, higher efficient photocatalysts for H 2 evolution may be developed in the near future. [ABSTRACT FROM AUTHOR]

In the present study, we propose an ionic coordination strategy for the design of a steroidal prodrug supramolecular hydrogel. The hydrogel composed of nanofibril networks formed spontaneously by the introduction of divalent cations (e.g., Mg 2+ , Ca 2+ , Zn 2+ and Fe 2+ ) and NH 4 + to a succinated dexamethasone (Dex-SA) aqueous solution at room temperature. The formation of the nanofibril structure was dominantly driven by the ionic coordination with the assistance of a delicate balance of multiple noncovalent interactions. A rheological analysis indicated that the formed Ca 2+ /Dex-SA supramolecular hydrogel exhibits dominant elastic and thixotropic properties. The formed Ca 2+ /Dex-SA supramolecular hydrogel allowed the gradual release of Dex and Dex-SA in vitro , and the drug release behaviour can be finely tuned by changing the Ca 2+ concentration. Storage stability studies showed that Dex-SA in hydrogel underwent an apparent chemical decomposition at 4 °C and 37 °C. In contrast, the Dex-SA xerogel was quite stable without any obvious chemical decomposition of Dex-SA in storage at −20 °C for 35 days, and it was able to turn into a hydrogel again within one minute after rehydration. The formed Ca 2+ /Dex-SA supramolecular hydrogel caused negligible cytotoxicity against HCEC and L-929 cells at drug concentrations up to 2 mM, as indicated by the in vitro cytotoxicity tests. Additionally, the proposed Ca 2+ /Dex-SA supramolecular hydrogel displayed a comparable anti-inflammatory efficacy with Dexp via the downregulation of NO, TNF-α and IL-6 expression in lipopolysaccharide (LPS)-activated RAW264.7 macrophage. Overall, the cation instructed steroidal prodrug supramolecular hydrogel might be a promising ophthalmic drug delivery system for anti-inflammatory therapy. [ABSTRACT FROM AUTHOR]

This paper reports synthesis of the first high internal phase emulsion (HIPE) system with double emulsion (DE) morphology (HIPE-DE). HIPE is a highly concentrated but highly stable emulsion system, which has a dispersed/internal phase fraction over 74 vol%. DE represents an emulsion system that hierarchically encapsulates two immiscible phases. The combination of HIPE and DE provides an efficient method for fabrication of complex structures. In this work, HIPE-DE having a water-in-oil-in-water (W/O/W) morphology has been prepared for the first time via a simple one-step emulsification method with poly(2-(diethylamino)ethyl methacrylate) (PDEA) microgel particles as Pickering stabilizer. An oil phase fraction up to 90 vol% was achieved by optimizing the microgel concentration in aqueous phase. The mechanism of the DE formation has been elucidated. It was found that while PDEA microgels stabilized the oil droplets in water, small amount protonated DEA monomers acted as surfactant and formed water-containing micelles inside the oil droplets. It was demonstrated that the W/O/W HIPE-DE could be precisely converted into porous polymer structures. With styrene as the oil phase in W/O/W HIPE-DE, porous polystyrene particles were obtained upon polymerization. With dissolved acrylamide as the aqueous phase and toluene as the continuous phase, porous polyacrylamide matrixes were prepared. Elevating temperature required for polymerization did not change the W/O/W HIPE-DE morphologies. This simple approach provides a versatile platform for synthesis of a variety of porous polymer systems. [ABSTRACT FROM AUTHOR]

Natural kaolinites often have a permanent charge due to mineralogical impurities preventing to link directly the morphology of the kaolinite particle to a selectivity coefficient between two cations for edge sites. In this study, kaolinites with no permanent charge were hydrothermally synthesized under different physicochemical conditions to obtain various morphologies (hexagon-shaped, more or less anisotropic). Na + and H + were chosen as the sorbed cations due to their ubiquitous presence in natural waters. For synthetic kaolinites for which no swelling layer was detected, an experimental sorption isotherm between Na + and H + was obtained. Data were interpreted using a surface complexation model, containing no electrostatic term, by considering the specific surfaces of lateral sites and sorption site density identified by crystallography for the different faces presented in the samples ((0 1 0), (1 1 0), (1 −1 0)). Selectivity coefficients between Na + and H + for all lateral sites characterizing a given morphology were calculated and validated in the [4–10] pH range, corresponding to the pH range for which dissolution can be considered negligible. The results showed that the Na + /H + selectivity coefficient depends strongly on the particle morphology and that the sorption properties of kaolinites cannot be obtained with good accuracy without a fine knowledge of the morphology of the particles. [ABSTRACT FROM AUTHOR]

Poly (AA co PVP)/PGS (PAPP) composite adsorbent was prepared by radical polymerization from Acrylic acid (AA), Polyvinylpyrrolidone (PVP) and Palygorskite (PGS), using N,N-methylenebisacrylamide (MBA) as cross-linker and potassium persulfate (KPS) as initiator. The PAPP was characterized with Fourier transform infrared (FT-IR), thermogravimetric analysis (TG), scanning electron microscope (SEM) and transmission electron microscopy (TEM). PAPP was used as adsorbent for the removal of methylene blue from aqueous solutions. The influences of pH, adsorption temperature and adsorption time on the adsorption properties of the composite to the dye were also investigated. Meanwhile, the adsorption rate data and adsorption equilibrium date were analyzed based on the pseudo-first-order and pseudo-second-order kinetic model, Langmuir and Freundlich isotherm models, respectively. The results indicating that the kinetic behavior better fit with the pseudo-second-order kinetic model. The maximum equilibrium adsorption capacity ( q m ) is 1815 mg/g at 289 K. The isotherm behavior can be explained by the Langmuir isotherm models. The activation energy was also evaluated for the removal of methylene blue onto PAPP. These results demonstrate that this composite material could be used as a good adsorbent for the removal of cationic dyes from wastewater. [ABSTRACT FROM AUTHOR]

[Display omitted] • A multifunctional composite with MOFs-derived urchin-like amorphous carbon anchored on nickel foam was fabricated. • The asymmetric supercapacitor achieved a high energy density of 0.036 mWh cm−3 at a power density of 0.984 mW cm−3. • The used UAC@NF could be reutilized to recycle Pb (II) from sewage. • This "waste to wealth" way will have a remarkable impact on energy and the environment. The booming development of carbon materials is of great value for diverse applications, owing to their superior electron conductivity, unique structures, and excellent cycle lifetime. This study presents two hierarchically structured amorphous carbon materials for asymmetric supercapacitor (ASC) device: i) the MOFs-derived urchin-like amorphous carbon anchored on nickel foam (UAC@NF) as positive electrode; ii) high temperature activated graphite carbon felt (GF500) as negative electrode. This ASC device achieves a higher energy density of 0.036 mWh cm−3 at a power density of 0.984 mW cm−3 and demonstrates better cycling performance with 91.4% capacitance retention after 10,000 cycles, compared with the other carbon-based supercapacitor. In addition, the UAC@NF after 10,000 cycles displays much better adsorption performance for Pb (II) compared with the unused UAC@NF. We have demonstrated the relationship between carbon materials' structure and performance by combining experiment and theoretical calculation. Predominantly, our work can provide a new direction for the common development of amorphous carbon materials in the field of energy and environment. [ABSTRACT FROM AUTHOR]

[Display omitted] Recently, carbon materials have attracted much attention in activating persulfate (PS) for the removal of organic pollutants. Seeking a greener, lower-cost, and higher-performance carbon material has become an important aspect of research. In this study, candle soot was innovatively used as a nanocarbon material, and its performance for PS activation was improved by simple ammonium ferric citrate modification. The optimal catalytic performance was achieved using 0.15 g/L modified candle soot (AS) and only 0.1 mM PS, with sulfamethoxazole (SMX) removal efficiency up to 95.5% within 120 min. Quenching tests, together with electron paramagnetic resonance measurements, showed that O 2 − and 1O 2 were the main reactive species for SMX degradation. Meanwhile, electron transfer pathway was also occurred. Various characterization results showed that graphitic N and carbonyl group were the main active sites for PS activation. Moreover, AS/PS system exhibited high catalytic activity and stability for SMX degradation over a wide initial pH range (3∼9), or even in the presence of Cl−, H 2 PO 4 − and NO 3 −. This work not only taps the potential of candle soot as an environmental functional material, but also showcases the roadmap for the discovery, design, and resource utilization of other waste carbon materials in wastewater treatment. [ABSTRACT FROM AUTHOR]

[Display omitted] Unevenly distributed polypyrrole (PPy) films/coatings with extensive "dead volumes" via electrodeposition have emerged as a main challenge for high energy density flexible supercapacitor. In this work, we have fabricated a phytic acid-guided graphite carbon felt/polypyrrole (GF@PA@PPy) 3D porous composite with less "dead volumes" via electrodeposition. After the activation of phytic acid (PA), the quantity and content of defects and oxygen-containing groups on the surface of carbon felt (GF) have increased. First, these functional groups improve the hydrophilicity of the surface of GF, resulting in the preferential uniform distribution of pyrrole monomer (Py). While significantly, the synergistic effects between the defects and oxygen-containing groups boost the attraction of pyrrole ring, and thus promotes the formation of perfect PPy films with less "dead volume" on GF. Finally, the supercapacitor assembled from the GF@PA@PPy-40 displays a high areal energy density of 0.0732 mWh cm−2, exceeding the previously reported PPy-based electrodes values. The deeper understanding of the role for the defects and oxygen-containing groups in the synthesis of PPy/carbon materials offers a new strategy to construct advanced PPy-based supercapacitors. [ABSTRACT FROM AUTHOR]

• PMMA particles are developed by emulsifier-free emulsion polymerization. • PMMA–HEMA particles could form crystalline structural color in HEMA solvent. • PMMA–HEMA–PDA particles with different amounts of melanin (PDA) doped are prepared. • PMMA–HEMA–PDA particle with 1.926 mM DA·HCl could improve the coloring of pHEMA film. Because of their flexible structure and adjustable color, structural colors with non-close-packed colloidal crystal arrays (NCCAs) have broad applications. However, most of these structural colors are limited by an approximate refractive index or high background scattering, and they present an unsatisfactory color that seriously hinders their practical application. Preparation of particles with a high refractive index or adsorption coefficient may be an effective approach to construct highly colorimetric NCCA structural colors in a nonaqueous solvent. The aim of this study was to explore the formation process of NCCA by the assembly of colloidal particles in a nonaqueous solvent, so as to fabricate NCCAs with a high refractive index and high adsorption. An attempt was made to fabricate the NCCA structural color by dispersing the desired particles in a 2-hydroxyethyl methacrylate (HEMA) solvent. Surface-functionalized poly(methyl methacrylate) (PMMA) particles were developed by emulsifier-free emulsion polymerization. The formation of NCCA was studied by comparing the dispersion of three classes of surface-functionalization of colloidal particles in the HEMA solvent. The melanin-like particles with a high refractive index and a high adsorption coefficient were synthesized by doping polydopamine (PDA) into good surface-functionalization particles by emulsifier-free emulsion polymerization. A highly colorimetric poly(2-hydroxyethyl methacrylate) (pHEMA) optical film with NCCA was fabricated by dispersing the melanin-like particles in a pHEMA hydrogel. PMMA-HEMA colloidal particles could successfully construct a NCCA structure in a nonaqueous HEMA solvent because of the solvation. Based on the "good particles," PMMA-HEMA-PDA colloidal particles, an initial 3-hydroxytyramine hydrochloride (DA·HCl) concentration of 1.926 mM was shown to significantly improve the colorimetric value of the final solidified NCCA hydrogel. These results provided an important reference for the construction of surfactant-free HEMA non-close-packed colloidal crystals. This highly colorimetric structurally colored hydrogel may be widely used in the design of a variety of colored intelligent sensors and soft devices. [ABSTRACT FROM AUTHOR]