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Hydrogen, as a clean and pollution-free energy with high calorific value, is one of the best alternatives to fossil fuels. Hydrogen evolution reaction (HER), as a half reaction of electrochemical water splitting, has also received extensive attention. At present, the development of low-cost and high-performance hydrogen evolution catalysts still faces enormous challenges. In this work, we synthesized a series of RuNi/TiO 2 -oxMWCNT catalysts with different Ru and Ni ratio. After optimizing the composition and proportion, RuNi/TiO 2 -oxMWCNT with Ru:Ni=4:6 has the optimal hydrogen evolution performance. High HER performance of extremely low 14.8 mV overpotential at 10 mA·cm−2 and 38.4 mV·dec−1 Tafel slope with perfect stability is achieved, which is superior to most reported ruthenium-based catalysts and even commercial Pt/C. XPS and UPS indicates that there is a metal synergistic effect of Ru and Ni and a strong SMSI between Ru and TiO 2 in the RuNi/TiO 2 -oxMWCNT catalyst, which helps to improve hydrogen evolution performance. This study provides a pathway for the rational design of multi-component nanostructured catalysts for HER. [Display omitted] • Bimetallic RuNi/TiO 2 -oxMWCNT catalysts were successfully fabricated by deposition-precipitation method. • The strong metal carrier interaction between Ru and TiO 2 optimizes the electronic structure of the catalyst. • The synergistic effect of bimetallic Ru-Ni tremendously improved the hydrogen evolution performance of catalysts. • The RuNi/TiO 2 -oxMWCNT shows an excellent HER performance with the low overpotential and Tafel slope. [ABSTRACT FROM AUTHOR]

In the present work, sodium alginate-based complex (flaxseed protein-sodium alginate) electrostatic complexes (FP-AG) were fabricated, acting as an effective emulsifier for the first time to stabilize Pickering high internal phase emulsions (HIPE). Interactions between FP and AG were evaluated by isothermal titration calorimeter and quartz crystal microbalance with dissipation monitoring. These results suggested that electrostatic interactions played a dominant role in FP-AG complexation, and stronger interactions between FP and AG occurred under acidic conditions, forming more viscoelastic layers. FP-AG complexes at pH 4.0 (FP-AG4) exhibited appropriate wettability (87.9°). HIPEs were prepared using FP-AG4 (HIPE-C), contrasted with FP at pH 8.0 (HIPE-P) as a control. Rheological results suggested that HIPE-C exhibited shear-thinning behavior (extrusion), high thixotropy (recovery), and high viscoelasticity (self-supporting), which possessed a great potential for 3D printing. Moreover, 3D printing and the stability of curcumin of HIPE were explored simultaneously for the first time. These results showed that HIPE-C exhibited outstanding printability and printing models presented smooth surfaces, regular shapes, and distinct resolution. HIPE-C showed a better protection for curcumin against ultraviolet and thermal treatments than HIPE-P. FP-AG complexes could be used as an effective HIPE stabilizer and novel edible ink with good 3D printability in food industry. [Display omitted] • FP-AG complexes could act as an effective emulsifier to stabilize HIPE. • Electrostatic interactions played a dominant role in FP-AG complexation. • Addition of AG could strengthen HIPE's network structure and mechanical strength. • HIPE-C showed outstanding extrudability and printability during 3D printing. • HIPE-C significantly protected Cur from degradation against UV and heat treatments. [ABSTRACT FROM AUTHOR]

There are few reports concentrated on the interactions between lipophilic surfactants and hydrophobized hollow TS-1 zeolite particles in the stabilization of emulsions. In this study, hydrophobized hollow TS-1 zeolite particles were synthesized and applied as emulsifier to stabilize the W/O Pickering emulsions employing cyclohexanone and water, and the influence of addition of lipophilic Span 80 on the stability of the W/O Pickering emulsions was systematically studied. Surprisingly, a phase inversion was induced by simply changing the Span 80 concentration. At fixed concentration of TS-1 zeolite particles (2 wt%), emulsions are water in oil (W/O) when the concentration of Span 80 is lower than 0.5 mM. Then the emulsions invert to oil in water (O/W) when the Span 80 concentration is between 1 mM and 8 mM. In this process, different emulsifiers dominate the composition of the interfacial layer, and the emulsion type is correspondingly controlled. When Span 80 concentration is lower than 0.5 mM, hydrophobized hollow TS-1 zeolite particles are in domination, and W/O emulsions are obtained. At Span 80 concentration of 1–8 mM, the emulsions are stabilized mainly by Span 80, and the emulsion type is O/W. A phase inversion was observed in the hydrophobized hollow TS-1 zeolite stabilized Pickering emulsion with addition of span 80. [Display omitted] • Hydrophobized hollow TS-1 zeolite was applied as emulsifier for the stabilization of Pickering emulsion. • A phase inversion was observed in the Pickering emulsions with addition of span 80. • Phase inversion of W/O to O/W is triggered through the formation of an intermediate O/W/O multiple emulsion. [ABSTRACT FROM AUTHOR]

Adsorbents with a large adsorption capacity and rapid removal rate are required for wastewater treatment containing heavy metal ions. Thus, CaAl-layered double hydroxide (CaAl-LDH) was successfully fabricated by a simple hydrothermal method as an efficacious sorbent to capture Cu(II) and Cd(II) ions in water. The as-synthesized CaAl-LDH exhibited the representative peaks of an LDH, good crystallinity, and a hexagonal lamellar structure. The entire adsorption process of CaAl-LDH for aqueous Cu(II) and Cd(II) was highly efficient and fast. The theoretical maximum removal capacities of CaAl-LDH for Cd(II) and Cu(II) were 1035.4 and 381.9 mg/g, respectively. Cu(II) and Cd(II) ions were adsorbed quickly in the first 60 min, and the kinetics data were generally consistent with a pseudo-second-order model. CaAl-LDH had a large distribution coefficient for Cd(II) (7.55 ×105 mL/g) and Cu(II) (4.78 ×105 mL/g). The possible mechanisms were precipitation, isomorphic substitution, and surface complexation. The results of this study demonstrate the potential applicability of CaAl-LDH for adsorption of heavy metals from aqueous solution. [Display omitted] • CaAl-LDH was synthesized by a hydrothermal method. • CaAl-LDH possessed a superhigh adsorption capacity for Cd(II) of up to 1035.4 mg/g. • The K d values of CaAl-LDH for Cd(II) and Cu(II) were larger than 105 mL/g. • The adsorption mechanisms involved precipitation, isomorphic substitution, and complexation. [ABSTRACT FROM AUTHOR]

To improve emulsification properties of pea protein isolate (PPI), PPI-maltodextrin-epigallocatechin-3-gallate (PPI-MD-EGCG) ternary conjugate was prepared for the first time by glycation and then covalent reaction under alkaline conditions. According to structural and physicochemical analysis of PPI-MD-EGCG ternary conjugate by circular dichroism, fluorescence spectroscopy, and Fourier transform infrared spectroscopy, PPI-MD-EGCG ternary conjugate showed the lowest peak intensity and surface hydrophobicity, while the highest emulsification and DPPH radical scavenging efficiency. These confirmed that interactions among protein, saccharide, and polyphenol destroyed the secondary structures of PPI. This may be that combination of glycation and covalent reaction can increase the unfolded conformation and the disordered secondary structures of proteins. PPI-MD-EGCG ternary conjugate was applied in curcumin-loaded emulsion based on ternary conjugate and linoleic acid containing curcumin. Potential of this ternary conjugate as a pH-controlled delivery and release system as well as bioaccessibility of curcumin were evaluated. Curcumin-loaded ternary conjugate emulsion showed the highest loading efficiency of 92.3% and stability. In vitro release properties suggested this ternary conjugate might be a good pH-controlled carrier for curcumin. Therefore, PPI-MD-EGCG ternary conjugate could be used as an effective delivery and release system. [Display omitted] • PPI-MD-EGCG ternary conjugate might be a good pH-controlled carrier for curcumin. • Glycation and polyphenol covalent reaction destructed PPI secondary structure. • PPI-MD-EGCG showed the lowest surface hydrophobicity. • PPI-MD-EGCG showed the highest emulsification property and antioxidant activity. • PPI-MD-EGCG could improve the loading ability and stability of Cur-loaded emulsion. [ABSTRACT FROM AUTHOR]

Design of catalyst particles bearing excellent diffusion performance and suitable surface wettability is of great importance to the successful application of Pickering interfacial catalysis. In this study, selective oxidation reactions over hydrophobized hollow TS-1 zeolite were applied as probe reactions to investigate the influence of catalyst diffusion performance closely related to mesopore size on its catalytic activity. Hydrophobized hollow TS-1 zeolite particles were prepared via a post desilication treatment accompanied with precrystallization treatment. The synthesized hydrophobized hollow TS-1 zeolite was characterized by Scanning electron microscopy, Transmission electron microscopy, X-ray diffraction, UV–vis absorption spectrometry, Fourier-transform infrared spectroscopy and Nitrogen adsorption-desorption. Stable Pickering emulsions including 1-hexene-hydrogen peroxide, cyclohexene-hydrogen peroxide and cyclohexanone-water were prepared with hydrophobized hollow TS-1 zeolite particles as emulsifier. HTS-1–393(2)-S zeolite synthesized with precrystallization at 393 K for 2 h presented the maximum values of 43.9 mol/(Ti-mol·h) for 1-hexene epoxidation, 15.7 mol/(Ti-mol·h) for cyclohexene epoxidation and 247.3 mol/(Ti-mol·h) for cyclohexanone ammoximation. In addition, HTS-1–393(2)-S zeolite particles displayed good reusability for more than five cycles. HTS-1–393(2)-S zeolite synthesized with precrystallization at 393 K for 2 h presented the maximum TOF values for 1-hexene epoxidation, cyclohexene epoxidation and cyclohexanone ammoximation in Pickering interfacial catalysis system. [Display omitted] • Hydrophobized hollow TS-1 zeolite was prepared via a post desilication and a post silylation modification treatment. • HTS-1–393(2)-S zeolite synthesized with precrystallization at 393 K for 2 h presented the maximum TOF value. • Precrystallization handlement induces a reduction of emulsion droplet size for HTS-1–393(2)-S zeolite. • Precrystallization handlement leads to decreased tetra-coordinated titanium and increased anatase TiO 2. [ABSTRACT FROM AUTHOR]

Radioactive aerosols in confined spaces of workplaces are the main source of internal radiation hazards for staff. Therefore, biomass-based electret fiber materials as alternatives of petroleum-based polymers will be of great potential in capturing radioactive aerosols due to its biodegradability, renewability and electrostatic effects. Herein, a fabrication strategy of bamboo pulp-based electret fiber aerogels by corona polarization is reported grounded on p-phenylenediamine (PPD)-modified bamboo pulp fibers (BCFs) and ethyl cellulose (EC). The morphology, chemical structure, and physical properties of BCFs before and after modification, as well as the electret properties and purification performance of fiber aerogel were analyzed. The results showed that PPD can be grafted uniformly on the surface of BCFs, making the fibers transform from irregular cylindrical shape with hierarchical surface to regular cylindrical shape with smooth surface, and can improve the surface potential of the fibers, one of the considerably great electret properties, from 0.00 kV to 1.33 kV when the graft amount of PPD was 0.500 g/g. The improvement in surface potential, leading by the grafted PPD structure which is a charge-trapping site confirmed by stoichiometric calculations, enhance the electrostatic trapping effect of the fibers on radioactive aerosol particles and shorten the purification time from 26 min to 15 min. Moreover, the electret fiber aerogel with modified BCFs (named as PPD-DABCFs) has a low air resistance of 56 Pa at the flow speed of 5.3 cm·s−1, a light base weight of 62.7 g·m−2 and a long service life. Therefore, the bamboo pulp-based electret fiber aerogel has a promising application in the field of radioactive aerogel purification. [Display omitted] • BCFs-based electret instead of petroleum polymer electret can increase its environmental friendliness. • The electret fabrication base on biomass materials is a sustainable development strategy. • The electret fiber aerogel has an excellent charge storage ability, light base weight and low resistance. • The electret fiber aerogel with 3D pore structure can be stable for long term use. [ABSTRACT FROM AUTHOR]

Framework doped iron materials such as Fe-MFI zeolite is an important heterogeneous Fenton-like catalyst for tetracycline degradation. Introduction of mesopore can enhance the tetracycline degradation performance for hollow Fe-MFI zeolite, however its positive effect is extremely limited ascribed to the essence of active sites of confined framework iron species. In this work, highly dispersed copper oxide on the hollow Fe-MFI zeolite CuO/FeS-1 was synthesized via an impregnation procedure and applied as heterogeneous catalyst for the tetracycline degradation. The synthesized CuO/FeS-1 was characterized by Scanning electron microscopy, Transmission electron microscopy, X-ray diffraction, UV–vis absorption spectrometry, Fourier transform infrared spectroscopy, Nitrogen adsorption-desorption and X-ray photoelectron spectroscopy. At pH = 7.0, CuO/FeS-1 revealed the highest tetracycline degradation rate of 99.6 % at experimental conditions: [TCE] = 30 mg/L, [PMS] = 1.0 g/L, [Catalyst] = 1.0 g/L, 333 K, and the largest degradation rate constant of 1.26 min−1, which was 3.4 folds of FeS-1 zeolite and 1.8 folds of CuO. Electron paramagnetic resonance (EPR) technology disclosed that •OH, SO 4 •−, 1O 2 and •O 2 − species were all the active species for CuO/FeS-1 zeolite in the tetracycline degradation. Furthermore, possible intermediates in the degradation of tetracycline over CuO/FeS-1 zeolite were identified with liquid chromatography-mass spectrometry (LC-MS). [Display omitted] [ABSTRACT FROM AUTHOR]

Fully conjugated organic polymer will be of great potential in removing uranium because of its superiority of structural designability, super stability and electron-rich property. Herein, a new pompon like fully-conjugated organic polymer (named as P-B) was synthesized by knoevenagel condensation using benzene-1,3,5-tricarboxal-dehyde (B) and p-xylylene dicyanide (P) as the building units which was a kind of n-type semiconductor being able to adsorb and detoxify U(VI). The micromorphology, physical properties, chemical structure, photoelectric performance and adsorption properties were characterized. The results showed that P-B was of three dimentional mesoporous microsphere rich in -C N with its maximum uranium adsorption being at 359 mg g−1. The adsorption kinetics conformed to the pseudo-second-order kinetic process, which indicated that chemical adsorption would be the main uranium capturing mechanism. Furthermore, the band gap of P-B manifested narrow with its conduction band (E CB) being of − 1.24 V which was more negative than the reduction potential of UO 2 2+ to UO 2 (0.411 V) which endowed P-B with a certain reduction capacity of uranium. XPS results disclosed the formation of U(Ⅳ), indicating the reduction of U(Ⅵ) actually occurred during the uranium capturing. In brief, the fully conjugated structure of P-B with -C N being contained endowed it strong coordination ability with uranium and favorable reduction ability. Therefore, P-B would be of great potential in capturing uranium in nuclear waste treatment. [Display omitted] • P-B have favorable uranium adsorption capacity with its maximum being at 359 mg g−1 and good selectivity of 88%. • P-B showed excellent acid and heat stability due to the fully conjugated π-electrons structure. • The fully conjugated structure and -C≡N endowed P-B with good photo-catalytic reduction and adsorption ability of uranium [ABSTRACT FROM AUTHOR]

TiO 2 is one of the more promising anode materials for sodium-ion batteries, but its poor electrical conductivity and slow Na+ diffusion kinetics limit its further development. Herein, C, N, P self-doping KTi 2 (PO 4) 3 /TiO 2 composites were successfully prepared by using lotus pollen as bio-template. And the experimental results show that the introduction of heteroatom and KTi 2 (PO 4) 3 into TiO 2 greatly contributes to improving the conductivity and Na+ mobility of TiO 2. The strategies provided in this paper can not only provide new ideas for the design and preparation of anode materials for TiO 2 -based sodium-ion batteries, but also provide new directions for the utilization of natural biomass. [Display omitted] ● The C, N, P self-doped KTi 2 (PO 4) 3 /TiO 2 with yolk shell structure will improve the conductivity and Na+ mobility of TiO 2. [ABSTRACT FROM AUTHOR]

Three symmetric cobalt porphyrins with different electron-donating substituents benzyl, triphenylamine-carbazole and carbazole at their meso -positions, nominated as Bz-CoPor ， Cb-CoPor and TPACb-CoPor , respectively, were selected to dope onto graphene oxide (GO) as the electrocatalysts to check the substituent effects on oxygen reduction reaction (ORR). The spectroscopic characterization of the composites suggests there is strong electronic coupling between porphyrin and GO. The substituent effects of porphyrins on ORR are examined using a series of electrochemical measurements, suggesting that the reduction potential, diffusion-limited current density and the electron transfer number as well as the H 2 O 2 generation yield can be strongly influenced by the porphyrin structure in acidic medium. Rotating ring-disk electrode (RRDE) tests suggest that TPACb-CoPor/GO exhibits the largest electron transfer number of 3.8 with the lowest H 2 O 2 generation yield of 9% within the three porphyrin/GO models. Our findings suggest that the substituent effects of porphyrins on ORR can still function at the π-π interaction interfaces, and these symmetric cobalt porphyrins can undergo nearly 4-electron transfer path upon using GO as the substrate. [Display omitted] • Three symmetric cobalt porphyrin-graphene oxide composites are fabricated. • The catalyst composites are studied in electrocatalytic oxygen reduction reaction. • Substituents of porphyrins show strong effect on the ORR activity. • The electron transfer numbers of all electrocatalysts are greater than 3.5. • The best composite TPACb-CoPor/GO exhibits an n of 3.8 and H 2 O 2 % of 9%. [ABSTRACT FROM AUTHOR]

Substituents can affect the partial charge distribution on porphyrin, and in tandem with the ion states in electrolyte, the charge transfer mechanism can be altered at catalytic interface. Three cobalt porphyrins with methyl phenyl, 2,1,3 -benzothiadiazole (BTD) and BTD-triphenylamine (TPA) substituents at the 5,15 -positions, nominated as CoPor , BTD-CoPor and TPA-BTD-CoPor , respectively, have been examined in oxygen reduction reactions (ORR) under alkaline condition. Reduced reduction potentials and enhanced response current densities were observed on the two substituent porphyrin-coated catalysts as compared to CoPor/C. Importantly, TPA-BTD-CoPor/C obtained slightly larger ORR current with less hydroperoxide anion generation yields than BTD-CoPor/C. We proposed that the electronic structure along with the induced partial charge effect caused the difference in ORR potential, while the electron-withdrawing property of BTD contributed to the increased response current. Though TPA unit still benefits the ORR performance, the more exposed cation orbitals on TPA that merit the acidic ORR activity was suggested to be ineffective in alkali condition. These findings demonstrate the importance of the induced intramolecular partial charges in affecting the catalytic process in alkali medium and point out the limitation in utilizing the structural merit of TPA in accelerating the interfacial charge transfer. [Display omitted] • Substituent effect on porphyrin is examined for ORR in alkaline electrolyte. • Both the electronic structure and partial charges affect the catalytic activity. • Introducing benzothiadiazole in porphyrin increases current but reduces potential. • OSET and ISET paths are proposed at the cobalt porphyrin catalytic ORR interface. [ABSTRACT FROM AUTHOR]

Although various kinds of adsorbents have good uranium adsorption capacity, they still meet the challenge in capturing uranium under highly acidic condition. Therefore, efficiently extracting uranium under strong acidic condition become the pursuit of researchers. In this study, a new phytic acid decorated porous organic polymers (POPs) named MA-U-PA was prepared by synthesizing a organic framework (MA-U) using melamine and uracil and with subsequent phytic acid modification. The results showed that the excellent stability of the prepared organic framework and strong uranium chelating ability of phytic acid endowed the as-prepared material being an excellent adsorbent under strong acidic condition. The adsorption capacity achieved 106.7 mg·g-1 at the pH of 1 which was much higher than that of MA-U and most of other adsorbents. The study of modification mechanism confirmed that the hydrogen bonds interaction of phytic acid with MA-U lead to the successful modification. In addition, the phosphonate groups of PA was mainly the active groups chelated with uranium. Moreover, the uranium adsorption process of MA-U-PA was in accordance with the pseudo-second-order kinetic and Langmuir isothermal model. The newly prepared phytic acid decorated porous organic material could achieve efficient uranium capturing from highly acidic nuclear wastewater. [Display omitted] • The raw materials were melamine, uracil and phytic acid which were relatively green and nontoxic. • The organic framework made the adsorbent stable and phosphoric groups on the surface endowed the adsorbent capturing uranium efficiently under strong acidic conditions. • The uranium adsorption capacity of MA-U-PA attained to 106.7 mg·g-1 under pH of 1, higher than most of other adsorbents. [ABSTRACT FROM AUTHOR]

The preparation of high-efficiency, stable and low-cost oxygen evolution reaction (OER) and hydrogen evolution reaction (HER) electrocatalysts is always a challenge for new energy systems. In this work, a simple hydrothermal synthesis method was used to obtain FeMn bimetallic organic materials (FeMn-MOF/NF) grown on foamed nickel (NF) in one step. Moreover, FeMn-MOF/NF(1:1) had larger electrochemical specific surface area and unique nano-flower-like structure. The overpotentials of OER and HER in alkaline solution at a current density of 50 mA·cm−2 were 290 mV and 260 mV, respectively, and the total water splitting potential at this current density is only 1.7 V. The excellent activity and stability were attributed to the synergistic effect of FeMn. The bimetal and abundant active sites could promote the release of oxygen during the catalytic process. [Display omitted] • FeMn-MOF/NF as bifunctional electrocatalyst exhibits superior HER and OER activity. • Simple preparation of FeMn-MOF with 3D nano-flower structure. • The voltage of the overall water splitting was 1.7 V at 50 mA cm−2. [ABSTRACT FROM AUTHOR]