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Hydrogel-based sensors commonly manifest pronounced swelling in aqueous milieus, a phenomenon that can precipitate deterioration of mechanical performance and distortion in output signals, thereby markedly constraining their expansive applicability. Drawing inspiration from the hierarchical heterogeneous cross-linking architecture inherent in biological tissues, an anti-swelling supramolecular hydrogel with robustness, fast self-recovery, and strain-sensitivity was meticulously engineered through leveraging the principles of multiple dynamic interaction matching. The heterogeneous structure for the hydrogels was constructed by integrating both 'rigid' carboxyl-Zr4+ coordination complexes and 'soft' hydrophobic micro-regions mediated by electrostatic interactions into the system. The synergistic interplay between reversible rigid and flexible cross-linking endowed the supramolecular hydrogels with robust mechanical properties, evidenced by a strength of 3.64 MPa, toughness of 6.83 MJ m−3, and complete self-recovery within 7 minutes, alongside anti-swelling capabilities in various aqueous environments, including acidic, alkaline, and saline solutions. Moreover, the hydrogels developed desirable sensing properties on account of the contribution of dynamic ions (Br−, Cl−, and Zr4+), enabling accurate signal output under diversified frequencies and strains. Consequently, these hydrogels were adapted to construct underwater sensors capable of transmitting information through Morse code. This bio-inspired design strategy achieved the perfect combination of mechanical, anti-swelling, and sensing properties in the hydrogels, offering novel insights into the fabrication of underwater sensors. [ABSTRACT FROM AUTHOR]

At present, the challenge of high-performance flexible piezoresistive pressure sensors remains the combination of high sensitivity and a wide monitoring range. The micro-morphological engineering of sensing materials will greatly contribute to the design and development of flexible piezoresistive sensors. Therefore, a flexible piezoresistive sensor based on a multi-layer interlocking "sandwich" structure was developed. The structure is assembled from polydimethylsiloxane (PDMS)/carbon nanotube (CNT) films with microdome arrays and thermoplastic polyurethane (TPU)/Ti3C2Tx MXene nanofiber films. The multi-layer interlocking structure not only significantly increases the contact area and sensitivity between layers, but also greatly improves mechanical and electrical stability. The results show that the PDMS/CNT–TPU/MXene pressure sensor has a high sensitivity of 82.17 kPa−1, a wide pressure detection range of 0–25 kPa, an extremely short response and recovery time of 100 ms, and an excellent dynamic cycling stability of more than 2000 cycles. In addition, the sensor has been used to perform comprehensive human motion monitoring, such as joint flexion, gait monitoring, and gesture recognition, demonstrating its potential for applications in health monitoring, wearable devices, and human–computer interaction. [ABSTRACT FROM AUTHOR]

Metal sulfides have been regarded as highly competitive anode materials for fast sodium storage due to their excellent redox reversibility and comparatively great electron properties. Nevertheless, metal sulfides suffer from serious structure collapse and capacity attenuation during fast cycling. Herein, the iron-based sulfide polycrystalline phase material grown in situ on hollow carbon nanofibers was synthesized (NHCFs-Fe7S8/FeS2). The construction of the polycrystalline phase is an effective strategy to enhance electron and ion transport, and improve the reaction kinetics of sodium ions. Meanwhile, the construction of a carbon network can effectively alleviate the volume expansion in the process of fast charge/discharge and maintain the stability of the structure. Thanks to these unique characteristics, NHCFs-Fe7S8/FeS2 exhibits a significantly enhanced electrochemical performance, which reveals outstanding long-term cycling stability (595.7 mA h g−1 at 1.0 A g−1 after 1000 cycles) and rate properties (154.7 mA h g−1 at 50.0 A g−1 and 107.0 mA h g−1 at 100.0 A g−1). The structure decoration method of metal sulfides can provide effective guidance for the design of other high-performance electrode materials for fast-charging sodium-ion batteries. [ABSTRACT FROM AUTHOR]

Alkaline earth metal cations are ubiquitously present in natural zeolites but less exploited in synthetic zeolites due to their low solubility in water, and hence it remains elusive how they contribute to zeolite formation. Herein, harmotome, a PHI-type zeolite with Ba2+, is readily synthesized from a Ba-containing aluminosilicate glass. This glass-to-zeolite transformation process, in particular the structure-regulating role of Ba2+, is investigated by anomalous X-ray scattering and high-energy X-ray total scattering techniques. The results demonstrate that the steady Ba2+–aluminosilicate interactions not only help prevent the precipitation of barium species under alkaline synthetic conditions, but also dictate the local structures with distinct interatomic distances between the Ba2+ and the surrounding aluminosilicate species throughout the transformation process, which lead to the successful formation of harmotome without detectable impurities. This study highlights the usefulness of the comprehensive X-ray scattering techniques in revealing the formation scheme of the zeolites containing specific metal species. In addition, a promising alternative approach to design and synthesize zeolites with unique compositions and topologies by using well-crafted glasses with suitable metal cation dopants is demonstrated. [ABSTRACT FROM AUTHOR]

Ultrahigh hydrogen evolution from photocatalytic water splitting using CaTiO3 is difficult due to its low photon-to-electron conversion efficiency. Herein, a facile post-loading strategy was developed for preparing a RuS2@CaTiO3-x heterojunction by anchoring RuS2 on a multi-shelled hollow cube of CaTiO3, which successfully achieved ultrahigh hydrogen evolution through water splitting with the assistance of a photocatalytic biorefinery. After RuS2 anchoring, the utilization of visible light and the separation/migration rate of photo-generated carriers of RuS2@CaTiO3-x enhanced significantly, resulting in a high photon-to-electron conversion efficiency. Correspondingly, the hydrogen evolution rate reached 8140.7 μmol g−1 h−1 in the RuS2@CaTiO3-10 system with the assistance of the photocatalytic selective oxidation of biomass-derived monosaccharides, and it was 45.5- and 4.2-fold greater than those of pristine CaTiO3 and RuS2, respectively. Furthermore, 89.0% yield of lactic acid was obtained in the corresponding system. Electron spin-resonance (ESR) characterization combined with radical capture experiments indicated that ˙OH played a significant role in lactic acid production. Moreover, RuS2@CaTiO3-10 not only exhibits excellent reusability and stability, but also has been successfully used for different biomass-based monosaccharide reforming coupled with water-splitting to co-produce lactic acid and hydrogen. This work sheds light on the development and design of photocatalytic systems. [ABSTRACT FROM AUTHOR]

The selective photocatalytic C–C bond cleavage of biomass coupling with H–O bond cleavage of water for co-producing chemicals and H2 is of great significance, but limited successes have been reported. In this study, a RuS2@CN-x photocatalyst with only exposed crystal face (200) was prepared by anchoring RuS2 nanoparticles on carbon nitride (CN) nanosheets and successfully used in photocatalytic C–C bond cleavage of biomass-based sugars coupling with water splitting to co-generate lactic acid and hydrogen. Interestingly, the RuS2 (200) crystal face combined with the interfacial synergism between CN and RuS2 in RuS2@CN-x effectively improved visible light absorption and enhanced the transfer/separation efficiency of photo-generated carriers. The RuS2@CN-2 exhibited superior photocatalytic activity towards synchronous water splitting and biomass conversion to co-produce hydrogen (8698.3 μmol g−1 h−1) and lactic acid (91.5%). Furthermore, the experimental and DFT calculation results indicated that the exposed crystal face (200) of RuS2 significantly enhanced the photocatalytic activity of RuS2@CN-2. Moreover, this reaction system not only has excellent recyclability but also displays excellent universality for small molecule biomass-derived monosaccharides and macromolecular xylan. This work provides a novel route to efficiently co-produce hydrogen and fine chemicals from photocatalytic C–C bond cleavage of biomass coupling with H–O bond cleavage of water. [ABSTRACT FROM AUTHOR]

High-efficiency visible-light-driven biomass conversion, coupled with water splitting, has attracted considerable attention, but the achievements have been rather limited. Herein, the ternary RuP2/Ti4P6O23@TiO2-7 photocatalyst was successfully constructed for efficient photocatalytic hydrogen evolution and high selectivity biomass conversion simultaneously. A series of nanospheres were uniformly arranged on the surface of RuP2/Ti4P6O23@TiO2-7, and it exhibited a fast photo-generated carrier rate and wide visible light absorption range due to the in situ incorporated RuP2 and Ti4P6O23 to form the heterojunction. The hydrogen evolution achieved 16.3 mmol g−1 h−1 accompanied by lactic acid production that reached 2.41 mmol g−1 h−1. Moreover, the RuP2/Ti4P6O23@TiO2-7 photocatalytic system is suitable for different biomass-derived monosaccharides and macromolecule xylan, in which the pentoses are more active than hexoses. For xylan, lactic acid production reached 0.63 g gxylan−1. Notably, this work shows an efficient utilization of water splitting and biomass conversion via RuP2/Ti4P6O23@TiO2-7 photocatalysis and provides new insight into biomass reforming and water splitting. [ABSTRACT FROM AUTHOR]

The simultaneous production of hydrogen and biomass-based chemicals from biomass-derived feedstock aqueous solutions via photocatalysis is appealing because no additional sacrificial agent is needed. However, limited success has been achieved. This paper reports efficient nori-shaped carbon nitride-based photocatalysts with potassium/oxygen co-doping and cyano group introduction for efficient conversion of biomass-derived monosaccharides to produce lactic acid and hydrogen simultaneously. The obtained photocatalyst has an adjustable bandgap, fast migration/separation rate of photo-generated carriers and displays excellent photocatalytic performance with respect to xylose conversion (∼95.0%), lactic acid selectivity (90.5%) and hydrogen generation (∼33 380 μmol g−1 h−1) in the presence of visible light. The h+, ˙OH, ˙O2− and 1O2 drive xylose conversion and lactic acid production. For biomass-derived pentoses and hexoses, the reaction system also exhibits excellent photocatalytic activity of lactic acid selectivity and hydrogen generation; the reported photocatalyst has excellent reusability. This paper provides a new perspective for hydrogen generation and biorefineries via a photocatalyst. [ABSTRACT FROM AUTHOR]

Interzeolite conversion, which refers to the synthesis of zeolites using a pre-made zeolite as the starting material, has enabled promising outcomes that could not be easily achieved by the conventional synthesis from a mixture of amorphous aluminum and silicon sources. Understanding the mechanism of interzeolite conversion is of particular interest to exploit this synthesis route for the preparation of tailor-made zeolites as well as the discovery of new structures. It has been assumed that the structural similarity between the starting zeolite and the target one is crucial to a successful interzeolite conversion. Nevertheless, an image as to how one type of zeolite evolves into another one remains unclear. In this work, a series of dealuminated FAU zeolites were created through acid leaching and employed as the starting zeolites in the synthesis of AEI zeolite under various conditions. This experimental design allowed us to create a comprehensive diagram of the interzeolite conversion from FAU to AEI as well as to figure out the key factors that enable this kinetically favourable crystallization pathway. Our results revealed different scenarios of the interzeolite conversion from FAU to AEI and pinpointed the importance of the structure of the starting FAU in determining the synthesis outcomes. A prior dealumination was proven effective to modify the structure of the initial FAU zeolite and consequently facilitate its conversion to the AEI zeolite. In addition, this strategy allowed us to directly transfer the knowledge obtained from the interzeolite conversion to a successful synthesis of the AEI zeolite from dealuminated amorphous aluminosilicate precursors. These results offer new insights to the design and fabrication of zeolites via the interzeolite conversion as well as to the understandings of the crystallization mechanisms. [ABSTRACT FROM AUTHOR]

Porphyrin-incorporating covalent organic frameworks were synthesized at room temperature. The resulting products with uniform morphology and excellent crystallinity exhibited good singlet oxygen generation ability. Both in vitro and in vivo experiments demonstrated the significant antitumor efficiency via sonodynamic therapy. [ABSTRACT FROM AUTHOR]

Fe2+–baicalein–polyethylene glycol (Fe–BaP) nanoparticles were synthesized by a room temperature wet chemical method via coordination between Fe2+ and baicalein. Fe–BaP possessed high photothermal conversion efficiency (η = 45.6%) and excellent antitumor efficacy was achieved with the synergistic photothermal/chemodynamic tumor therapy. [ABSTRACT FROM AUTHOR]

N2O is typically present as a trace gas in chemical processes, but its emission causes serious environmental issues. We herein demonstrate that ion-exchanged mordenite zeolites (framework code: MOR) can exhibit high capacities for N2O adsorption under ambient conditions. In particular, a natural MOR zeolite gives an adsorption capacity as high as 0.34 mmol-N2O per g-zeolite (1 atm, 25 °C), representing the best performing material among all zeolite-based adsorbents reported so far. The results contribute toward a comprehensive understanding of the structure–activity relationship and offer insights to establishing a zeolite-based adsorption system for enriching or removing N2O. [ABSTRACT FROM AUTHOR]

A simple and efficient photocatalytic method for the synthesis of dihydropyrimidinones (DHPMs) and their derivatives via porous ultrathin carbon nitride nanosheets (p-CNNs) without solvents was demonstrated. The yields of 3,4-dihydropyrimidin-2(1H)-ones/thiones and their derivatives were up to 97.0%. Furthermore, the yield of 5-ethoxycarbonyl-6-methyl-4-phenyl-3,4-dihydropyrimidin-2(1H)-one in the 10th cycle retained 98.9% of its 1st value. Considering the environmental and economic benefits, this work exhibits various merits including excellent yields, environmental friendliness, inexpensiveness, and avoiding the use of solvents and metal-based photocatalysts. In addition, the excellent performance of the p-CNNs and environmentally benign reaction system have also been checked by the photocatalytic synthesis of 12-phenyl-9,9-dimethyl-8,9,10,12-tetrahydrobenzo[a]xanthen-11-one and 5-phenyl-1(4-methoxyphenyl)-3[(4-methoxy-phenyl)-aminol]-1H-pyrrol-2(5H)-one. This work paves a new way for carrying out a three-component reaction using metal-free photocatalysts under mild reaction conditions. [ABSTRACT FROM AUTHOR]

The function of pressure has long been overlooked in the hydrothermal synthesis of zeolites, which is typically carried out under an autogenous pressure (below 2 MPa). We herein report, the first of its kind, a detailed investigation on the hydrothermal synthesis of zeolites under external high pressures, where crystallization behaviors contradicting the common observations were generated. [ABSTRACT FROM AUTHOR]

A mild alkaline treatment with the assistance of surfactants has proved to be an effective way to introduce uniform mesopores into zeolites, yielding hierarchical materials with superior catalytic performance. Accelerating this process may open new opportunities in the scale-up of this new class of materials. In this study, we present an ultrafast surfactant-templating (UST) approach achieved within only a few minutes for the fast production of mesoporous ultra-stable Y (USY) zeolites by combining several favorable factors including high treating temperature, reactors featuring fast heating, and optimized reagent composition. Temperatures in the range of 150–220 °C yielded high quality materials, while too high temperatures (260–280 °C) produced inferior samples. The use of a flow reactor allowed for completing the UST in just one minute, which evidences the remarkable structural flexibility of zeolites that can reorganize in such a short time to accommodate a large amount of intracrystalline mesoporosity, without compromising their integrity or main properties. [ABSTRACT FROM AUTHOR]

High-silica erionite (ERI) zeolites are conventionally synthesised via a so-called charge density mismatch (CDM) approach, and a typical synthesis takes several days to complete. We herein demonstrate an ultrafast route to synthesise high-silica erionite zeolites in as short as 2 h at 210 °C. The fast-synthesised ERI has been proved to show higher hydrothermal stability compared with the conventionally synthesised product. [ABSTRACT FROM AUTHOR]

We present herein an ultrafast, organic structure-directing agent (OSDA)-free synthesis of mordenite zeolite in a tubular reactor capable of fast heating. Using a typical Na2O/SiO2/Al2O3 system, the synthesis time was shortened to 10 min, which is much shorter than the time required by conventional methods (tens of hours). The addition of milled seeds, which have a smaller crystal size (200 nm), was found to be more effective in enhancing the crystallization than the micrometer-sized raw seeds (2 μm). The fast-synthesized mordenite possesses properties similar to those of mordenite synthesized by conventional methods in terms of crystallinity while having a comparably small crystal size. In addition, the effects of the alkalinity and SiO2/Al2O3 ratio of the initial reactant mixture on the crystallization rate were evaluated, but no significant effects were observed. On the contrary, the yield and SiO2/Al2O3 ratio of the product were dependent on the alkalinity and SiO2/Al2O3 ratio of the initial reactant mixture. Based on these observations, the crystallization behavior of mordenite, obtained from an ultrafast, OSDA-free synthesis method, is discussed. [ABSTRACT FROM AUTHOR]

We herein present a top-down methodology to prepare nanosized zeolites with tunable size by combining post-synthesis milling and fast recrystallization of several minutes (10 min for SSZ-13 and 5 min for AlPO4-5). A continuous-flow recrystallization process is demonstrated to further enhance the overall product efficiency. [ABSTRACT FROM AUTHOR]

Herein, we report a rapid route for the synthesis of AlPO4-5. By combining fast heating in a tubular reactor with a seed-assisted method, both of which were found to be crucial, the preparation of AlPO4-5 was completed in one minute, making this route the fastest known for the preparation of the crystalline microporous materials. [ABSTRACT FROM AUTHOR]

The selective photocatalytic C–C bond cleavage of biomass coupling with H–O bond cleavage of water for co-producing chemicals and H2 is of great significance, but limited successes have been reported. In this study, a RuS2@CN-x photocatalyst with only exposed crystal face (200) was prepared by anchoring RuS2 nanoparticles on carbon nitride (CN) nanosheets and successfully used in photocatalytic C–C bond cleavage of biomass-based sugars coupling with water splitting to co-generate lactic acid and hydrogen. Interestingly, the RuS2 (200) crystal face combined with the interfacial synergism between CN and RuS2 in RuS2@CN-x effectively improved visible light absorption and enhanced the transfer/separation efficiency of photo-generated carriers. The RuS2@CN-2 exhibited superior photocatalytic activity towards synchronous water splitting and biomass conversion to co-produce hydrogen (8698.3 μmol g−1 h−1) and lactic acid (91.5%). Furthermore, the experimental and DFT calculation results indicated that the exposed crystal face (200) of RuS2 significantly enhanced the photocatalytic activity of RuS2@CN-2. Moreover, this reaction system not only has excellent recyclability but also displays excellent universality for small molecule biomass-derived monosaccharides and macromolecular xylan. This work provides a novel route to efficiently co-produce hydrogen and fine chemicals from photocatalytic C–C bond cleavage of biomass coupling with H–O bond cleavage of water. [ABSTRACT FROM AUTHOR]

Alkaline earth metal cations are ubiquitously present in natural zeolites but less exploited in synthetic zeolites due to their low solubility in water, and hence it remains elusive how they contribute to zeolite formation. Herein, harmotome, a PHI-type zeolite with Ba 2+ , is readily synthesized from a Ba-containing aluminosilicate glass. This glass-to-zeolite transformation process, in particular the structure-regulating role of Ba 2+ , is investigated by anomalous X-ray scattering and high-energy X-ray total scattering techniques. The results demonstrate that the steady Ba 2+ -aluminosilicate interactions not only help prevent the precipitation of barium species under alkaline synthetic conditions, but also dictate the local structures with distinct interatomic distances between the Ba 2+ and the surrounding aluminosilicate species throughout the transformation process, which lead to the successful formation of harmotome without detectable impurities. This study highlights the usefulness of the comprehensive X-ray scattering techniques in revealing the formation scheme of the zeolites containing specific metal species. In addition, a promising alternative approach to design and synthesize zeolites with unique compositions and topologies by using well-crafted glasses with suitable metal cation dopants is demonstrated.

Fe 2+ -baicalein-polyethylene glycol (Fe-BaP) nanoparticles were synthesized by a room temperature wet chemical method via coordination between Fe 2+ and baicalein. Fe-BaP possessed high photothermal conversion efficiency (η = 45.6%) and excellent antitumor efficacy was achieved with the synergistic photothermal/chemodynamic tumor therapy.

Small amounts of Fe(NO 3 ) 3 were added to the synthesis mixture prior to the hydrothermal synthesis of Bi 4 Ti 3 O 12 microspheres. The physicochemical properties of the resulting materials were changed accordingly. The photocatalytic activities of several samples were studied through the photocatalytic degradation of organic pollutants. The samples with a theoretical Fe atomic percentage of 5.9% showed the highest photocatalytic activity among these samples. The main active species in photocatalytic degradation was demonstrated by radical capturing experiments as h + . The introduction of a suitable amount of Fe to the photocatalyst can facilitate the separation of electron-hole pairs generated upon light irradiation, inhibit their recombination efficiently, and prominently expand the light absorption region, thus leading to higher photocatalytic activity., Competing Interests: There are no conflicts to declare., (This journal is © The Royal Society of Chemistry.)

Herein, we report a rapid route for the synthesis of AlPO4-5. By combining fast heating in a tubular reactor with a seed-assisted method, both of which were found to be crucial, the preparation of AlPO4-5 was completed in one minute, making this route the fastest known for the preparation of the crystalline microporous materials.