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• The most active catalyst, featuring Pt decoration on the Ni surface, activated within the first 10 h and preserved its activity over a 48-hour aging process. • CNTs on the Pt-Ni bimetallic catalyst showed a tendency to develop and migrate towards the support, displaying an increasing number of structural defects without entirely covering the metal active sites. • In contrast, the Ni/Al 2 O 3 catalyst experienced the accumulation of crystalline, low-defect CNTs, which enveloped Ni active sites over time, leading to rapid deactivation. Deactivation induced by coke deposition remains the foremost challenge in using Ni-based catalysts for the production of syngas via dry reforming of methane (DRM) reaction. Herein, highly dispersed Pt-Ni/Al 2 O 3 bimetallic catalysts prepared by atomic layer deposition (ALD) displayed remarkable stability at 650 ℃ in the DRM reaction. The Pt-Ni catalysts underwent an activation process within the initial 10 h and maintained its activity without deactivation throughout the subsequent aging testing up to 48 h. In contrast, the Ni/Al 2 O 3 rapidly deactivated over time. Despite its high CH 4 conversion rates, the Pt-Ni bimetallic catalyst produced a substantial quantity of carbon nanotubes (CNTs) analogous to the Ni/Al 2 O 3 catalyst. The discrepancy in stability performance between two catalysts derived from disparities in the carbon sites and structural defects evolving over reaction time. Regarding the catalysts with Pt decoration on the Ni surface, CNTs exhibited increasing structural defects and gradually deposited on the Al 2 O 3 support without fully encapsulating the metal active sites, as evidenced by CH 4 -TPD experiments. In the case of Ni nanoparticles on Al 2 O 3 , crystalline CNTs with fewer defects accumulated, leading to rapid deactivation. These findings enhance our understanding of coke resistance in DRM catalysts and help the development of more robust bimetallic catalyst systems. [ABSTRACT FROM AUTHOR]

[Display omitted] • The fabricated UIO-la-CoN-rGO aerogel possesses the properties of hydrophobic, anti-corrosion, heat insulation, infrared stealth and electromagnetic wave absorption. • The UIO-la-CoN-rGO aerogel achieves high EMW absorbing performance, with reflection loss of −44.8 dB and effective absorbing bandwidth (EAB) of 7.28 GHz. • The UIO-la-CoN-rGO aerogel shows an impedance value of 1.5 × 105 Ω·cm2 after being soaked in 3.5 % aqueous NaCl for 30 d with an anti-corrosion efficiency of 99.149 %. • The introduction of heteroatoms enriches the defect sites of the materials, thus increasing the interfacial polarization and dipole polarization. In addition to having a superior electromagnetic wave (EMW) absorption profile, materials of this type that are applied in complex and extreme environments must be hydrophobic, anti-corrosive, heat insulating and infrared stealth. In the described investigation, a multifunctional UIO-la-CoN-rGO aerogel that possesses all of these properties was fabricated by using a hydrothermal and freeze drying process. Lauric acid (la) is incorporated into this aerogel to enlarge pore sizes and enhance hydrophobicity of the Zr-based metal organic framework (UIO-66) component. The large interfacial and dipole polarization caused by anchoring UIO-66 nanospheres to the Co,N co-doped graphene nanosheets results in a high EMW absorbing performance, reflected in a minimum reflection loss (RL min) of −44.8 dB and a wide effective absorbing bandwidth (EAB) of 7.28 GHz. In addition, the aerogel displays high levels of hydrophobicity, anti-corrosiveness, heat insulation and infrared stealth. For example, UIO-la-CoN-rGO has a water contact angle of 142.5°and a surface temperature that remains nearly unchanged after more than 1 h at 100 ℃. Moreover, the UIO-la-CoN-rGO coating gives the aerogel an impedance value of 1.5 × 105 Ω·cm2 after being soaked in 3.5 % aqueous NaCl for 30 d, and an anti-corrosion efficiency of 99.149 %. The results of this study provide guidance for the design of multifunctional EMW absorbing materials that function in complex environments. [ABSTRACT FROM AUTHOR]

[Display omitted] • CuFe 2 O 4 /g-C 3 N 4 was prepared by secondary microwave co-precipitation. • Ferromagnetic resonance effect enhanced the oxidation property of CuFe 2 O 4 /g-C 3 N 4. • Adsorption effect of the catalyst in high-salinity environments was greatly promoted. • CuFe 2 O 4 /g-C 3 N 4 enabled 100 % removal of tetracycline from mariculture wastewater. • The photo-Fenton system would not impair the healthy growth of clownfish. Superior separation of photogenerated carriers holds the key to intensive degradation of tetracycline (TC) in mariculture wastewater under natural sunlight. CuFe 2 O 4 /g-C 3 N 4 (CFO/g) was synthesized by secondary microwave co-precipitation (SMCP) based on the ferromagnetic resonance absorption effect. Under the reaction conditions of pH = 6.5, CFO/g = 0.2 g/L, [H 2 O 2 ] = 1 mM, 99.0 % TC removal was realized in 40 min. Enhanced performance for TC removal in high-salinity environments heavily relied on elevated ionic strength and rapid electron transfer of CFO/g in conjunction with high-salinity interactions. To ecologically remediate mariculture wastewater under natural sunlight, we immobilized powdered CFO/g to a ferrite magnet and devised a continuous flow reaction apparatus, incorporating the controlled injection of hydrogen peroxide (H 2 O 2), to achieve the 100 % TC removal and simultaneously undertake the pretreatment of other contaminants (∼70 %). Ultimately, a safety assessment demonstrated that the degradation of mariculture wastewater by the CFO/g photo-Fenton system is a reliable and efficient technology, and the growth of clownfish remained unimpaired. SMCP successfully accelerated the conversion of high-valent metal ions to low-valent ones and eased the activation barriers of H 2 O 2 , enabling various active species to execute their respective roles productively. Innovative application of microwave resonance to enhance the magnetic properties of CFO/g and to support the equilibrium conversion of elemental valence states in high-salinity environments from real wastewater. [ABSTRACT FROM AUTHOR]

[Display omitted] • The fabricated FeNi-MOF-rGO aerogels exhibits remarkable EMW absorption performances with strong RL and broad EAB at the thickness of 2.9 mm (−48.3 dB and 8.32 GHz) whereas the filling contents are just 5 %. • The morphology and structure of MOF are regulated by electron transfer of GO and the obtained MOF with unique strip or regular octahedral shape results in vast heterojunction interfaces. • The electron transfer was further confirmed by DFT differential density and Bader charge analysis and the interfacial polarization of the material was confirmed by finite element simulation. Graphene and its derivatives have become the star materials in the field of electromagnetic wave (EMW) absorption, and have been widely studied because of their unique structure and excellent properties. However, the high electrical conductivity of graphene-based material leads to poor impedance matching performances, so it often needs to be annealed at high temperatures, which is a intricate procedure and cause the waste of energy. Herein, we develop a convenient strategy to synthesize metal organic framework-reduced graphene oxide (MOF-rGO) aerogels through facile hydrothermal and freeze drying procedure. Firstly, the excessive electrons on graphene can be transferred to MOF, in this way, no annealing is needed. Secondly, the morphology and structure of MOF can be regulated electronically to endow the material with rich heterojunction interfaces and enhance its interfacial polarization. Thirdly, the synthesized aerogels satisfy the requirements of thin thickness, low density and light weight. The fabricated Ni-MOF-rGO and FeNi-MOF-rGO aerogels exhibit remarkable EMW absorption performances with strong reflection loss (RL) and broad effective absorption band (EAB) at the thickness of 2.4 (−47.8 dB and 7.84 GHz) and 2.9 mm (−48.3 dB and 8.32 GHz) whereas the filling contents are just 5 %. Moreover, the attenuation capacity of the fabricated aerogels are verified through the radar-section simulation and the interfacial polarization loss are confirmed by the COMSOL analogue simulation. In a word, this work provides a new afflatus and inspiration for the design of graphene-based EMW absorption materials. [ABSTRACT FROM AUTHOR]

[Display omitted] • The composite membrane has superhydrophilicity and underwater superoleophobicity. • The composite membrane demonstrates enhanced UV cleaning capabilities. • The composite membrane achieves over 100% flux recovery rate under UV irradiation. • The composite membrane can continuously separate emulsion with excellent parameters. • The composite membrane shows superior oil resistance and durability. In the emulsion separation process, the adhesion of oil-contamination severely hampers the long-term operation of ceramic membranes, and photocatalytic membranes present a promising approach to mitigate membrane fouling and enhance membrane performance. The present study describes the fabrication of a novel Al 2 O 3 @GO-TiO 2 composite photocatalytic membrane through a two-step dip-coating method. TiO 2 particles were uniformly deposited onto the surface of the pristine membrane via a thermal coating method, while the pleated graphene oxide (GO) formed a laminar-flow-like coating through stirring-ultrasonication, ultimately being stably anchored to the composite membrane's surface by co-built connections with TiO 2. Due to the successful coating of hydrophilic groups, the composite membrane exhibited super hydrophilic-underwater superoleophobic properties to separate stable water-in-diesel emulsions with excellent permeation flux (4347.17 L∙m−2∙h−1) and oil removal rate (94.98 %). The composite membrane showed excellent oil resistance stability and durability in severe environment hydrodynamic washout and cycling tests. In addition, the combined modification of GO-TiO 2 endowed the composite membranes with strong photocatalytic ability, which made the membranes exhibit a good recovery of membrane performance in the separation of oilfield-produced water (OPW). The thick oil layer was completely removed by •OH, •O 2 – and 1O 2 generated by UV irradiation excitation. After 6 h of operation, the flux and oil removal rate of the Al 2 O 3 @GO-TiO 2 membrane were 31.91 % and 2.1 % higher than those of the Al 2 O 3 @TiO 2 membrane, demonstrating enhanced light self-cleaning performance. The exceptional oil–water separation capability coupled with its efficient photocatalytic degradation potential positions the ceramic membrane as a promising solution for treating actual OPW. [ABSTRACT FROM AUTHOR]

[Display omitted] • Functionalized electrospun nanofibers were applied for the uranium extraction. • Hyperbranched amidoxime groups with assistant groups were grafted. • Photothermal conversion ability was also introduced into the fibers. • The nanofiber adsorbents showed good antibacterial activity. • The uranium extraction capacity reached 9.54 mg g−1 from natural seawater. Uranium extraction from natural seawater is critical to addressing the shortage of uranium resources, but it is a giant challenge. The amidoxime-based adsorbent is regarded as one of the most promising materials for uranium capture, whereas still suffers from low adsorption site utilization and poor selectivity toward U(VI) against V(V). Herein, hyperbranched amidoxime group grafted photothermal electrospun fibers (AOPEI-C-PAN fibers) were reported for highly efficient uranium extraction from seawater. Carbon nanotubes (CNTs) were blended into the electrospun fibers to introduce the photothermal character. Hyperbranched grafting could improve the content of the amidoxime group and bring an assistant group (the amine group). Owing to the large content of functional groups, synergetic coordination interaction and photothermal conversion ability, the novel fiber adsorbents realized a fast adsorption rate (shortening the equilibrium time to 36 h from 60 h compared with the dark condition), high uranium uptake (1738.5 mg g−1 from the Langmuir model) from the uranium spiked seawater and excellent selectivity in U/V binary system (selectivity coefficient = 85.8). Furthermore, Ag nanoparticles could also be loaded onto the CNTs to endow the fibers with antibacterial activity, thereby preventing biofouling. As a result, the uranium extraction capacity of the fiber adsorbent reached 9.54 mg g−1 after 28 days' simulated sunlight irradiation of contact with circular seawater, which is 62.0 % higher than that under dark condition. This study reveals that AOPEI-C-PAN fiber adsorbent holds great potential in practical uranium extraction applications. [ABSTRACT FROM AUTHOR]

[Display omitted] • ZnCrO x spinel is prepared and mixed with SAPO-34 for syngas conversion. • Concentration of precipitant influences oxygen vacancy concentration. • Hydrogen calcination contributes to generate more oxygen vacancies. • More oxygen vacancies promote the chemisorption and conversion of CO. • A CO conversion of 43 % and a C 2 =-C 4 = selectivity of 86 % are achieved. Metal oxides play a crucial role in catalytic activity of bifunctional catalyst for directly converting syngas into light olefins. A series of ZnCr oxides were synthesized with varying concentrations of precipitant and different atmospheres of precipitate treatment via co-precipitation method. The characterization results indicate that suitable concentration of precipitant and hydrogen calcination contribute to the generation of more oxygen vacancies that can promote the chemical adsorption of CO. Density function theory calculations confirmed that the adsorption energy of CO could be decreased with increasing concentration of oxygen vacancies, and that the formation energy of oxygen vacancies was lower under the hydrogen atmosphere as compared to the oxygen atmosphere. The catalytic activity demonstrated that more oxygen vacancies promoted the chemisorption and conversion of CO. The ZnCr oxide obtained through hydrogen calcination exhibited the highest concentration of oxygen vacancy and achieved a C 2 =-C 4 = selectivity of 86 % and a CO conversion of 43 % at 4 MPa and 5400 mL g−1h−1 combined with SAPO-34 zeolite. These findings suggest that increasing oxygen vacancy concentration on the surface of metal oxides is an effective approach for designing high-performance catalysts for directly converting syngas into light olefins. [ABSTRACT FROM AUTHOR]