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Photo-Fenton catalysis plays an important role in the degradation of organic pollutants in environmental sewage. In this paper, magnetic 0D/1D ZnFe2O4/ZnCO3 rod-like nanocomposites were fabricated by a simple one-pot solvothermal method, and then the produced magnetic 0D/1D ZnFe2O4/ZnO rod-like nanocomposites were formed via calcination at high temperature. The obtained 0D/1D ZnFe2O4/ZnCO3 has been fully investigated by x-ray diffraction, field-emission scanning electron microscopy, transmission electron microscopy, x-ray photoelectron spectroscopy, and vibrating sample magnetometry. Furthermore, the photocatalytic Fenton reaction of these two catalysts has been preliminarily evaluated for the degradation performance of organic dyes and antibiotics in wastewater. The results showed that, under visible-light irradiation, the ZnFe2O4/ZnCO3 composite material and its product, ZnFe2O4/ZnO, after high-temperature firing can achieve more than 90% photo-Fenton catalytic degradation of Rhodamine B (RhB) and tetracycline (TC) within 30 min, superior to that of ZnFe2O4, ZnCO3 , and ZnO monomers due to their larger specific surface area and more active sites. The magnetization saturation values of ZnFe2O4/ZnCO3-2 and ZnFe2O4/ZnO-2 were, respectively, around 34.20 emu/g and 15.00 emu/g, indicating that both have good magnetic recovery properties. After five cycles of experiments, the photo-Fenton catalytic properties of ZnFe2O4/ZnCO3-2 and ZnFe2O4/ZnO-2 on TC decreased slightly within 30 min, but the Fenton catalytic properties of RhB still maintained more than 98%, indicating that both have good magnetic recovery properties and strong structural stability. A possible photo-Fenton catalytic mechanism has been proposed based on free radical identification, electrochemical impedance spectra, photocurrent curves, and a Mott–Schottky diagram. This study provided two catalysts with excellent performance for the photo-Fenton catalytic degradation of pollutants in water. [ABSTRACT FROM AUTHOR]

WO3/C3N4 porous nanotubes (WO3/CNNT) with direct Z-scheme heterojunction have been developed through an effortless one-pot calcination self-assembly strategy. The synthesized WO3/CNNT heterojunction structure is different from conventional bulk g-C3N4 according to field-emission scanning electron microscope (FE-SEM), transmission electron microscope (TEM), and X-ray photoelectron spectroscopy (XPS) spectra analysis, and has a better performance in photocatalytic degradation of pollutants. It is under a unique structure with an elevated interfacial area and high dispersion active sites, which can facilitate the degradation of some dye pollutants and antibiotics by heterojunctions, higher than that of bulk g-C3N4 and hollow g-C3N4 nanotubes. The photocatalytic experimental results indicated the optimum photocatalyst of the 2% WO3/CNNT sample with a BET surface area of 108.8 m2/g, which can rapidly remove Rhodamine B (RhB) and tetracycline (TC) up to 97.4% and 87.4%, respectively, under visible-light irradiation, which was about 3.4 and 83.8 times higher than that of individual CNNT and WO3 for RhB degradation. Additionally, the degradation of TC was around 1.1 and 14.3 times superior to that of individual CNNT and WO3. Furthermore, the porous WO3/CNNT heterojunction turned out to be stable and reusable after four cycles of experiments. Reactive free radical trapping experiments confirmed that holes (h+) and superoxide (·O2−) radicals are the most dominant species during photodegradation. Finally, a possible Z-scheme catalytic mechanism is proposed. In this work, some new insights are provided to design novel Z-scheme g-C3N4-based heterojunction photocatalysts with a porous nanotube structure and enhanced photocatalytic performance for high-efficiency degradation of dyes and antibiotics. [ABSTRACT FROM AUTHOR]

A panchromatic light-absorbing [70]fullerene-perylene-BODIPY triad (C70-P-B) was synthesized and applied as a heavy atom-free organic triplet photosensitizer for photooxidation. The photophysical processes were comprehensively investigated by the methods of steady-state spectroscopy, time-resolved spectroscopy, as well as theoretical calculations. C70-P-B shows a strong absorption ability from 300–620 nm. Efficient cascading intramolecular singlet-singlet energy transfer in C70-P-B was confirmed by the luminescence study. The backward triplet excited state energy transfer from C70 moiety to perylene then occurs to populate 3perylene*. Thus, the triplet excited states of C70-P-B are distributed on both C70 and perylene moiety with lifetimes of 23 ± 1 μs and 175 ± 17 μs, respectively. C70-P-B exhibits excellent photooxidation capacity, and its yield of singlet oxygen reaches 0.82. The photooxidation rate constant of C70-P-B is 3.70 times that of C70-Boc and 1.58 times that of MB, respectively. The results in this paper are useful for designing efficient heavy atom-free organic triplet photosensitizers for practical application in photovoltaics, photodynamic therapy, etc. [ABSTRACT FROM AUTHOR]

As one of the "miracle materials" in the 21st century, aerogels with ultra‐low weight and remarkable mechanical performance have emerged and shown incredible immunity to harsh working environments, attracting substantial research interests across a wide range of areas. Recently, exploitation of MXene nanosheets into aerogels represents a new research focus in the field of materials science, on account of their unique structures and outstanding properties. In this review, the aim is to provide a timely and insightful overview for the recent advances in the fabrication, performance, and application of MXene‐based aerogels. The main strategies for constructing MXene‐based aerogels, directly from MXene‐dispersion or in the presence of other functional components, are summarized. Furthermore, the desirable performance of MXene‐based aerogels and their related applications in the areas including electromagnetic management, sensors, solar steam generators, and energy storage are highlighted. A thorough investigation and comparison of their mechanical, electrical, sensing, and other properties are performed to understand the structure‐property relationships. At last, this study is concluded with summary and outlook section on the future development as well as challenges that remained, thus bringing new research opportunities for the material engineering and functional application of MXene‐based aerogels. [ABSTRACT FROM AUTHOR]

Integration of both excellent mechanical performance and remarkable durability into composite hydrogel materials is highly demanded yet challenging. Herein, a synergistic strategy of combining covalent crosslinks with nanosheet‐reinforced dynamic interactions is developed for the design and fabrication of deformable and recoverable nanocomposite hydrogels. Layered double hydroxide nanosheets and a trace amount of covalent crosslinks are simultaneously incorporated into the network, providing profound synergy in mechanical enhancement and durability extension. The resultant materials displayed high deformability (stretchability >1100%, compressibility >90%), considerable springiness and resilience, rapid and excellent recovery over 2000 cycles of compression and retraction as well as a 100% hysteresis ratio after only 1 min during large stretching. Notably, these networks are also transparent and ionically conductive. To demonstrate the utility, a wearable strain sensor is constructed for sensing and detecting human motions (e.g., subtle movement of mouth‐opening and large motion of joint‐bending), exhibiting a linear response with high sensitivity (gauge factor as high as 7.66) over 100–300% strain. This line of research will inspire renewed interest and work into synergic exploitation of nanospecies‐reinforced interactions and covalent crosslinks into the design of high‐performance composite materials. [ABSTRACT FROM AUTHOR]