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• Novel Bi 2 WO 6 -ZnBi 2 O 4 heterojunction was prepared by sonochemical assisted hydrothermal method. • Sonochemical pretreatment caused spherical to flake-like morphology evolution. • The optimal Bi 2 WO 6 -20ZnBi 2 O 4 revealed good stability (4% loss) after 5 cycling runs. • Direct Z-scheme mechanism was proposed for the enhanced photodegradation of MG. • Bi 2 WO 6 -ZnBi 2 O 4 can efficiently remove both MG dye and colorless 2,4-DCP contaminants. In this work, novel Bi 2 WO 6 -ZnBi 2 O 4 p-n heterojunction was successfully synthesized through combination of sonochemical and hydrothermal procedures. The results revealed that the sonochemically prepared nanocomposites had spherical shape with amorphous structure which became crystalline particles with flak-like morphology after hydrothermal treatment. Bi 2 WO 6 -ZnBi 2 O 4 nanocomposite with 20 wt% ZnBi 2 O 4 content demonstrated the highest photocatalytic performance compared to the pure Bi 2 WO 6 and ZnBi 2 O 4 samples toward the degradation of Malachite Green (MG). This finding is associated with the efficient separation of photo-generated electron/hole pairs due to the formation of interfacial charge transfer between Bi 2 WO 6 and ZnBi 2 O 4. However, further ZnBi 2 O 4 loading had no significant effect on the enhancement of photocatalytic activity of nanocomposite samples owing to the shielding effect of ZnBi 2 O 4 against incident light. The obtained results were further verified by optical and photocurrent density measurements. Based on the obtained results from active species trapping experiments, electron spin resonance and Mott-Schottky calculations, the Z-scheme charge transfer pathway was proposed as the predominant mechanism for the photocatalytic reactions. Also, the photocatalytic degradation of 2,4-dichlorophenol, as a colorless model pollutant, was conducted on optimal composite sample to study the possible contribution of MG dye sensitization mechanism in the enhancement of photocatalytic efficiency. [ABSTRACT FROM AUTHOR]

[Display omitted] • We designed and developed a novel HER catalyst of ruthenium nanoparticles supported on oxide carbon nanotubes (Ru@OCNT-700). • For HER performance in alkaline media (1 M KOH), the as-formed Ru@OCNT-700 reaches 10 mA cm−2 at an overpotential of 13.2 mV with a Tafel slope of 45.4 mV dec−1. • Through the characterization of the surface and structure of the catalyst sample, the interaction between ruthenium metal and carrier was analyzed. "Cracking" water is of great significance to develop (HER) catalysts with high catalytic performance for non-platinum hydrogen evolution under alkaline conditions. In this paper, we prepared a ruthenium nanoparticle catalyst on oxidized carbon nanotubes (Ru@OCNT) support. Electrochemical tests showed that Ru@OCNT-700 exhibited excellent catalytic performance and good stability under alkaline conditions (1 M KOH). When the current density reached 10 mA cm−2, it only needed an overpotential of 13.2 mV. The Tafel slope was 45.4 mV/dec−1. Due to its excellent HER performance, Ru@OCNT electrocatalyst could have broad applicability in large-scale hydrogen production. [ABSTRACT FROM AUTHOR]

Vanadium nitride (VN) is a promising electrode material for sodium-ion storage due to its multivalent states and high electrical conductivity. However, its electrochemical performance has not been fully explored and the storage mechanism remains to be clarified up to date. Here, the possibility of VN/carbon hybrid nanorods synthesized from a metal-organic framework for ultrafast and durable sodium-ion storage is demonstrated. The VN/carbon electrode delivers a high specific capacity (352 mA h g -1 ), fast-charging capability (within 47.5 s), and ultralong cycling stability (10 000 cycles) for sodium-ion storage. In situ XRD characterization and density functional theory (DFT) calculations reveal that surface-redox reactions at vanadium sites are the dominant sodium-ion storage mechanism. An energy-power balanced hybrid capacitor device is verified by assembling the VN/carbon anode and active carbon cathode, and it shows a maximum energy density of 103 Wh kg -1 at a power density of 113 W kg -1 ., (© 2024 Wiley‐VCH GmbH.)

Skin cutaneous melanoma (SKCM), a form of skin cancer, ranks among the most formidable and lethal malignancies. Exploring tumor microenvironment (TME)-based prognostic indicators would help improve the efficacy of immunotherapy for SKCM patients. This study analyzed SKCM scRNA-seq data to cluster non-malignant cells that could be used to explore the TME into nine immune/stromal cell types, including B cells, CD4 T cells, CD8 T cells, dendritic cells, endothelial cells, Fibroblasts, macrophages, neurons, and natural killer (NK) cells. Using data from The Cancer Genome Atlas (TCGA), we employed SKCM expression profiling to identify differentially expressed immune-associated genes (DEIAGs), which were then incorporated into weighted gene co-expression network analysis (WGCNA) to investigate TME-associated hub genes. Discover candidate small molecule drugs based on pivotal genes. Tumor immune microenvironment-associated genes (TIMAGs) for constructing TIMAS were identified and validated. Finally, the characteristics of TIAMS subgroups and the ability of TIMAS to predict immunotherapy outcomes were analyzed. We identified five TIMAGs (CD86, CD80, SEMA4D, C1QA, and IRF1) and used them to construct TIMAS. In addition, five potential SKCM drugs were identified. The results showed that TIMAS-low patients were associated with immune-related signaling pathways, high MUC16 mutation frequency, high T cell infiltration, and M1 macrophages, and were more favorable for immunotherapy. Collectively, TIMAS constructed by comprehensive analysis of scRNA-seq and bulk RNA-seq data is a promising marker for predicting ICI treatment outcomes and improving individualized therapy for SKCM patients., (© 2024. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.)

The use of porous hard carbons (PHCs) as electrode materials in sodium-ion batteries has great potential; however, the exposure of large surface areas to electrolyte flow results in irregular and irreversible solid electrolyte interfaces (SEIs), leading to deteriorated ionic and electronic mobility and inferior initial Coulombic efficiency (ICE). These issues can be addressed through suitable structural modifications of PHC materials. Herein, the integration of high-surface-area PHCs with carbon nanofibers (CNFs) was accomplished by a simple electrospinning technique, which resulted in a uniform and reversible SEI layer. In the meantime, the CNFs' mesh provided connectivity and conductivity in the as-integrated electrodes, whereas PHCs offered fast diffusion kinetics and high Na + ion storage capacity. Additionally, PHC integration with CNFs demonstrated an excellent ICE of 77% and a specific capacity of 505 mAh/g at 25 mA/g. Furthermore, the conjugated microstructure also provided flexibility and stability to the electrode (260 mAh/g after 500 cycles). This remarkable synergy may promote the development of free-standing, flexible, and highly porous properties in a single material for advanced energy storage applications.

Pt single-atom materials possess an ideal atom economy but suffer from limited intrinsic activity and side reaction of producing H 2 O 2 in catalyzing the oxygen reduction reaction (ORR); platinum alloys have higher intrinsic activity but weak stability. Here, we demonstrate that anchoring platinum alloys on single-atom Pt-decorated carbon (Pt-SAC) surmounts their inherent deficiencies, thereby enabling a complete four-electron ORR pathway catalysis with high efficiency and durability. Pt 3 Co@Pt-SAC demonstrates an exceptional mass and specific activities 1 order of magnitude higher than those of commercial Pt/C. They are durable throughout 50000 cycles, showing only a 10 mV decay in half-wave potential. An in situ Raman analysis and theoretical calculations reveal that Pt 3 Co core nanocrystals modulate electron structures of the adjacent Pt single atoms to facilitate the intermediate absorption for fast kinetics. The superior durability is attributed to the shielding effect of the Pt-SAC coating, which significantly mitigates the dissolution of Pt 3 Co cores. The hybridizing strategy might promote the development of highly active and durable ORR catalysts.

Electrocatalysts for the oxygen reduction reaction (ORR) play a central role in fuel cells and zinc-air batteries. Bimetal single atoms and nanoparticle hybrids are emerging ORR electrocatalysts, superior to the most exploited unary metal single-atom catalysts (SACs). Here, we report bimetal SAC-based nanofiber networks of Co 3 Fe 7 @Co/Fe-SAC for efficient ORR electrocatalysis and zinc-air batteries. A facile and easy-to-scale-up process is developed, and the versatility is validated in three hybrids. Strong electronic interaction is revealed between bimetal single atoms and alloy nanoparticles, leading to improved catalytic performances for ORR. Specifically, the Co 3 Fe 7 @Co/Fe-SAC hybrids exhibit a half-wave potential of 0.841 V in a basic electrolyte, comparable to the Pt/C electrocatalyst. Assembled in a zinc-air battery, a Co 3 Fe 7 @Co/Fe-SAC hybrid-based cell demonstrates a power density 1.8 times higher than the benchmark Pt/C-IrO 2 -based one, and it is stable for 150 cycles galvanostatic charge/discharge. The superior device performance is attributed to the appealing intrinsic activity, the carbon shielding effect for anti-leaching, and the hierarchical porous networks for large accessibility of active sites and favorable mass transport. Theoretical calculations suggest that alloy nanoparticles significantly improved the intrinsic catalytic activity of Fe single-atom sites at the expense of slightly lowering the activity of Co single-atom sites. This work presents a versatile process for the mass production of efficient composite electrocatalysts and highlights the power of bimetal single-atom-based hybrids and hierarchically porous structures for ORR device performances.

Hemerocallis fulva is a medical and edible plant. In this study, we optimized the ultrasound-assisted extraction (UAE) process of extracting flavonoids from Hemerocallis fulva leaves by single-factor experiments and response surface methodology (RSM). The optimum extraction conditions generating the maximal total flavonoids content was as follows: 70.6% ethanol concentration; 43.9:1 mL/g solvent to sample ratio; 61.7 °C extraction temperature. Under the optimized extraction conditions, the total flavonoid content (TFC) in eight Hemerocallis fulva varieties were determined, and H. fulva (L.) L. var. kwanso Regel had the highest TFC. The cytotoxicity of the extract was studied using the Cell Counting Kit-8 (CCK-8 assay). When the concentration was less than 1.25 mg/mL, the extract had no significant cytotoxicity to HaCaT cells. The antioxidant activity was measured via chemical antioxidant activity methods in vitro and via cellular antioxidant activity methods. The results indicated that the extract had a strong ABTS and •OH radical scavenging activity. Additionally, the extract had an excellent protective effect against H2O2-induced oxidative damage at a concentration of 1.25 mg/mL, which could effectively reduce the level of ROS to 106.681 ± 9.733% (p < 0.001), compared with the 163.995 ± 6.308% of the H2O2 group. We identified five flavonoids in the extracts using high-performance liquid chromatography (HPLC). Infrared spectroscopy indicated that the extract contained the structure of flavonoids. The results showed that the extract of Hemerocallis fulva leaves had excellent biocompatibility and antioxidant activity, and could be used as a cheap and potential source of antioxidants in the food, cosmetics, and medicine industries.

2D transition metal carbides and/or nitrides, so-called MXenes, are noted as ideal fast-charging cation-intercalation electrode materials, which nevertheless suffer from limited specific capacities. Herein, it is reported that constructing redox-active phosphorus-oxygen terminals can be an attractive strategy for Nb 4 C 3 MXenes to remarkably boost their specific capacities for ultrafast Na + storage. As revealed, redox-active terminals with a stoichiometric formula of PO 2 - display a metaphosphate-like configuration with each P atom sustaining three PO bonds and one PO dangling bond. Compared with conventional O-terminals, metaphosphate-like terminals empower Nb 4 C 3 (denoted PO 2 -Nb 4 C 3 ) with considerably enriched carrier density (fourfold), improved conductivity (12.3-fold at 300 K), additional redox-active sites, boosted Nb redox depth, nondeclined Na + -diffusion capability, and buffered internal stress during Na + intercalation/de-intercalation. Consequently, compared with O-terminated Nb 4 C 3 , PO 2 -Nb 4 C 3 exhibits a doubled Na + -storage capacity (221.0 mAh g -1 ), well-retained fast-charging capability (4.9 min at 80% capacity retention), significantly promoted cycle life (nondegraded capacity over 2000 cycles), and justified feasibility for assembling energy-power-balanced Na-ion capacitors. This study unveils that the molecular-level design of MXene terminals provides opportunities for developing simultaneously high-capacity and fast-charging electrodes, alleviating the energy-power tradeoff typical for energy-storage devices., (© 2022 The Authors. Advanced Materials published by Wiley-VCH GmbH.)

Lithium-ion capacitors (LICs) have attracted intense attention due to their high energy/power densities and good stability. However, their performance is severely limited by the imbalance in reaction kinetics and electrochemical capacity between the faradaic battery-like anodes and non-faradic capacitive cathodes. Here, we propose an all alginate-derived LIC assembled with a three-dimensional porous orthorhombic phase Nb 2 O 5 /C hybrid as the anode, seaweed-derived carbon as the cathode and sodium alginate (SA) as the electrode binder. The increase in the rate performance of the anode and the capacity of the cathode efficiently mitigates the mismatch between the counter electrodes, and the SA binder provides facilitated access for Li ions to the surfaces of electrode materials. The all alginate-derived LIC exhibits high energy (143.9 W h kg -1 at 87.6 W kg -1 ) and power (17.5 kW kg -1 at 75.1 W h kg -1 ) densities with a superior cyclability (84.6% capacity retention after 3000 charge-discharge cycles), surpassing those of previous Nb 2 O 5 -based LICs. This work provides a novel design strategy for the electrodes of next-generation high-performance LICs., Competing Interests: There are no conflicts to declare., (This journal is © The Royal Society of Chemistry.)

Continuous development and advancement in modern detection technologies have increased the demand for multiband (e.g., visual and infrared) compatible camouflage. However, challenges exist in the requirements of incompatible structure resulting from the adaptation to different camouflage effects. This study is inspired by the light absorption structure of butterfly wing scales and demonstrates a porous anodic alumina/aluminum flake powder material prepared by a microscopic powder anodic oxidation technique for visual and infrared camouflage. The fabricated structures manipulate a compromise condition for visual camouflage by low reflectance ( R ̅ 400-800nm = 0.32) and dual-band infrared camouflage by low emission (ε̅ 3-5μm = 0.081 and ε̅ 8-14μm = 0.085). Further, the characteristic of short-range disorder in these bioinspired structures allows maintenance of the camouflage performance under omnidirectional detection (0-60°). This study provides new insight and a feasible method for coordinated manipulation of electromagnetic waves via bioinspired structural design and improved fabrication.

Dense, thick, but fast-ion-conductive electrodes are critical yet challenging components of ultrafast electrochemical capacitors with high volumetric power/energy densities 1-4 . Here we report an exfoliation-fragmentation-restacking strategy towards thickness-adjustable (1.5‒24.0 μm) dense electrode films of restacked two-dimensional 1T-MoS 2 quantum sheets. These films bear the unique architecture of an exceptionally high density of narrow (sub-1.2 nm) and ultrashort (~6.1 nm) hydrophobic nanochannels for confinement ion transport. Among them, 14-μm-thick films tested at 2,000 mV s -1 can deliver not only a high areal capacitance of 0.63 F cm -2 but also a volumetric capacitance of 437 F cm -3 that is one order of magnitude higher than that of other electrodes. Density functional theory and ab initio molecular dynamics simulations suggest that both hydration and nanoscale channels play crucial roles in enabling ultrafast ion transport and enhanced charge storage. This work provides a versatile strategy for generating rapid ion transport channels in thick but dense films for energy storage and filtration applications., (© 2021. The Author(s), under exclusive licence to Springer Nature Limited.)

Graphitic carbon nitride (g-C 3 N 4 ) is a promising photocatalyst for CO 2 reduction to alleviate the greenhouse effect. However, the low light absorption, small specific surface area, and rapid charge recombination limit the photocatalytic efficiency of g-C 3 N 4 . Herein, we demonstrate a bioinspired nanoarchitecturing strategy to significantly improve the light harvesting and charge separation of the g-C 3 N 4 /Au composite, as proven by the remarkable photocatalytic CO 2 reduction. Specifically, a biotemplating approach is employed to transfer the sophisticated hierarchical structures and the related light-harvesting functionality of Troides helena butterfly wings to the g-C 3 N 4 /Au composite. The resulting g-C 3 N 4 /Au composite shows high photocatalytic efficiency under UV-visible excitation with triethanolamine as the sacrificial agent. The yields of CO and CH 4 are 331.57 and 39.71 μmol/g/h, respectively, which are ∼36 times and ∼88 times that of pure g-C 3 N 4 under the same conditions. Detailed experiments and the finite-difference time-domain method suggest that the superb photocatalytic activity should be ascribed to the unique periodic hierarchical structure which assists the light absorption and the localized surface plasmon resonance for promoted charge separation in addition to the more effective CO 2 diffusion and larger specific surface area. Our work provides a new path for the design and optimization of photocatalysts based on biological structures that are usually unattainable artificially.

In this project, Sn-Fe bimetallic nanoparticles were prepared by a facile method. The bimetallic nanoparticles of it could be well established by a field emission scanning electron microscope micrographs. Due to the excellent synergistic influence between Sn-Fe nanoparticles and leucine indicated a great performance for determination of Cr 3+ . The material was characterized using the XRD, DLS, and zetasizer for theevaluation of crystal structure and morphologyinformation.The potential and effective size of Sn-Fe NPs was -29.10 mV and 30 nm, respectively. Cr 3+ ions interaction with the Sn-Fe NPs-leucine probe was carried out in 1 min as response time. The limit of detection of Sn-Fe NPs for Cr(III) colorimetric method was 0.25 nM. The prepared nanoparticles showed impressive photocatalysis efficiency for degradation of MO was about 95.1% in 35 min, thus the prepared nanoparticles may be developed for the detoxification of pollution. The prepared nanoparticles depicted effective antibacterial activity againstC. botulinum and, H. pylori bacteria., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2021 Elsevier B.V. All rights reserved.)

The performance and cost of electrocatalysts play an important role in the development and application prospects of energy conversion technology. Single-atom catalysts (SACs) have constituted a new frontier in the field of catalytic science in recent years. As a non-precious metal, iron (Fe)-SACs show great potential in the field of electrocatalysis, which is comparable to or even better than the performance of precious metal catalysts. However, a robust, generic synthetic strategy toward atomically dispersed Fe catalysts is still lacking, which is still a formidable challenge to maintain the dispersion of Fe atoms at high temperatures and to obtain high catalytic activity. In this review, the latest progress in the synthesis of Fe-SACs is introduced and summarized, and the electrochemical applications of Fe-SACs are further summarized and discussed. Herein, the relationship between the structural characteristics and performance of Fe-SACs is further introduced and discussed. Finally, the existing problems and development prospects of Fe-SACs are discussed., Competing Interests: The authors declare no conflict of interest., (This journal is © The Royal Society of Chemistry.)

As attractive materials for photoeletrochemical hydrogen evolution reaction (PEC HER), conjugated polymers (e.g., conjugated acetylenic polymers [CAPs]) still show poor PEC HER performance due to the associated serious recombination of photogenerated electrons and holes. Herein, taking advantage of the in situ conversion of nanocopper into Cu 2 O on copper cellulose paper during catalyzing of the Glaser coupling reaction, a general strategy for the construction of a CAPs/Cu 2 O Z-scheme heterojunction for PEC water reduction is demonstrated. The as-fabricated poly(2,5-diethynylthieno[3,2-b]thiophene) (pDET)/Cu 2 O Z-scheme heterojunction exhibits a carrier separation efficiency of 16.1% at 0.3 V versus reversible hydrogen electrode (RHE), which is 6.7 and 1.4-times higher respectively than those for pDET and Cu 2 O under AM 1.5G irradiation (100 mW cm -2 ) in the 0.1 m Na 2 SO 4 aqueous solution. Consequently, the photocurrent of the pDET/Cu 2 O Z-scheme heterojunction reaches ≈520 µA cm -2 at 0.3 V versus RHE, which is much higher than pDET (≈80 µA cm -2 ), Cu 2 O (≈100 µA cm -2 ), and the state-of-the-art cocatalyst-free organic or organic-semiconductor-based heterojunctions/homojunctions photocathodes (1-370 µA cm -2 ). This work advances the design of polymer-based Z-scheme heterojunctions and high-performance organic photoelectrodes., (© 2020 The Authors. Published by Wiley-VCH GmbH.)

Due to the potential application in the future energy conversion system, there is an increasing demand for efficient, stable and cheap platinum-free catalysts for hydrogen evolution. However, it is still a great challenge to develop electrocatalysts with high activity similar to platinum or even higher, especially those that can work under alkaline conditions. Ruthenium (Ru), as a cheap substitute for platinum, has been studied as a feasible substitute for (HER) catalyst for hydrogen evolution reaction. In this paper, we designed and developed a novel Ru catalyst (Ru@CNT) supported on nitrogen-doped carbon nanotubes. Electrochemical tests show that even under alkaline conditions (1 M KOH), Ru@CNT still shows excellent catalytic performance and good durability. It only needs 36.69 mV overpotential to reach a current density of 10 mA cm -2 , and its Tafel slope is 28.82 mV dec -1 . The catalytic performance of the catalyst is comparable to that of 20% Pt/C. The significant activity is mainly attributed to the chelation of highly dispersed ruthenium atoms on nitrogen-doped carbon nanotubes. Secondly, the one-dimensional pore structures supported by nitrogen heterocarbon nanotubes can provide more opportunities for active centers. Excellent HER performance makes Ru@CNT electrocatalyst have a broad application prospect in practical hydrogen production., Competing Interests: The authors declare no conflict of interest., (This journal is © The Royal Society of Chemistry.)

Natural biological systems are constantly developing efficient mechanisms to counter adverse effects of increasing human population and depleting energy resources. Their intelligent mechanisms are characterized by the ability to detect changes in the environment, store and evaluate information, and respond to external stimuli. Bio-inspired replication into man-made functional materials guarantees enhancement of characteristics and performance. Specifically, butterfly architectures have inspired the fabrication of sensor and energy materials by replicating their unique micro/nanostructures, light-trapping mechanisms and selective responses to external stimuli. These bio-inspired sensor and energy materials have shown improved performance in harnessing renewable energy, environmental remediation and health monitoring. Therefore, this review highlights recent progress reported on the classification of butterfly wing scale architectures and explores several bio-inspired sensor and energy applications., (© The Author(s) 2020. Published by Oxford University Press on behalf of China Science Publishing & Media Ltd.)

Sophisticated metastructures are usually required to broaden the inherently narrowband plasmonic absorption of light for applications such as solar desalination, photodetection, and thermoelectrics. Here, nonresonant nickel nanoparticles (diameters < 20 nm) are embedded into cellulose microfibers via a nanoconfinement effect, producing an intrinsically broadband metamaterial with 97.1% solar-weighted absorption. Interband transitions rather than plasmonic resonance dominate the optical absorption throughout the solar spectrum due to a high density of electronic states near the Fermi level of nickel. Field solar purification of sewage and seawater based on the metamaterial demonstrates high solar-to-water efficiencies of 47.9-65.8%. More importantly, the solution-processed metamaterial is mass-producible (1.8 × 0.3 m 2 ), low-cost, flexible, and durable (even effective after 7 h boiling in water), which are critical to the commercialization of portable solar-desalination and domestic-water-purification devices. This work also broadens material choices beyond plasmonic metals for the light absorption in photothermal and photocatalytic applications., (© 2020 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.)

A new ternary composite of 1T-molybdenum disulfide, hexagonal tungsten trioxide, and reduced graphene oxide (M-W-rGO) is synthesized by using a one-pot hydrothermal process. The synergetic effect of 1T-MoS 2 and hexa-WO 3 nanoflowers improves the electrochemical performance for supercapacitors by inducing additional active sites and hexagonal tunnels, respectively, which lead to high storage capacity and easy transfer of electrolyte ions. The ternary M-W-rGO composite has a high specific capacitance of 836 F g -1 at 1 A g -1 , which is nearly twice that of binary composites of M-rGO and W-rGO with high capacitance retention of 86.35 % after 3000 cycles at a high current density of 5 A g -1 . This study provides a new ternary composite that can be used as an electrode material for high-performance supercapacitors., (© 2019 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.)

Assembling two-dimensional (2D) nanomaterials into three-dimensional (3D) hierarchical structures with novel functions is challenging and has attracted considerable attention. However, it is quite difficult to obtain complex 3D architectures of 2D materials with a uniform and intact structure using traditional methods, such as hydrothermal/solvothermal methods and direct precipitation methods. Here, we use butterfly wing scales as bio-templates to prepare 3D hierarchical BiOCl/Au wing scales for plasmonic photocatalysis. The as-prepared materials exhibit excellent photodegradation of rhodamine B (RhB) under visible light. The degradation rates of BiOCl microspheres and BiOCl and BiOCl/Au butterfly wing scales are 48.8%, 72.6%, and 93.8%, respectively, within 20-min illumination at the same loading capacities. This excellent performance of BiOCl/Au is attributed to the coupling of enhanced carrier separation efficiency and the effect of localized surface plasmon resonance (LSPR) aroused by 3D metallic structures. This study provides a relatively facile method to obtain complex 3D constructure of 2D materials. It also demonstrates a nature-led route to prepare highly efficient plasmonic photocatalysts.

Assembling nanosized building blocks into macroscopic 3D complex structures is challenging. Here, nanosized metal and semiconductor building blocks with a variety of sizes and shapes (spheres, stars, and rods) are successfully assembled into a broad range of hierarchical (nanometer to micrometer) assemblies of functional materials in centimeter size using butterfly wings as templates. This is achieved by the introduction of steric hindrance to the assembly process, which compensates for attraction from the environmentally sensitive hydrogen bonds and prevents the aggregation of nanosized building blocks. Of these materials, Au nanostar assemblies show a superior enhancement in surface-enhanced Raman scattering (SERS) performance (rhodamine 6G, 1506 cm -1 ) under 532, 633, and 780 nm excitation-this is 3.1-4.4, 3.6-3.9, and 2.9-47.3 folds surpassing Au nanosphere assemblies and commercial SERS substrates (Q-SERS), respectively. This method provides a versatile route for the assembly of various nanosized building blocks into different 3D superstructures and for the construction of hybrid nanomaterials and nanocomposites., (© 2019 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.)

Surface modification for templated synthesis is crucial to achieving three-dimensional (3D) architectured materials for catalysis, photonics, energy storage, etc. However, the existing facile and versatile modification methods (e.g. with dopamine and catechol) generate modification layers that are unstable in harsh environments. These methods are thus unsuitable for electrical applications. Here we report that Ce4+ can act as an effective surface modification reagent for a broad range of substrates (chitinous butterfly wings, carbon paper, nickel foam, and polyethylene terephthalate planks) with various structural features owing to its strong oxidizing ability and Lewis acid nature. The modification yields discrete CeO2 seed layers on substrate surfaces in ca. 0.25-2 h, important for the subsequent conformal growth of CeO2 nanoparticles, Ni(OH)2 nanowires, FeOOH nanosheets, and WO3 nanosheets into 3D architectured materials. The conformally synthesized FeOOH on nickel foam (NF) yields an overpotential of 241 mV at 10 mA cm-1 for an oxygen evolution reaction. This value is comparable to a typical catalyst Ni(Fe)OOH-NF for which the Ni/Fe ratio must be well-optimized. This facile and versatile strategy might have broad applications in the conformal fabrication and application of 3D architectured materials, especially when applied in electrical applications of architectured materials (e.g. Li-ion battery).

Hard carbon attracts wide attentions as the anode for high-energy rechargeable batteries due to its low cost and high theoretical capacities. However, the intrinsically disordered microstructure gives it poor electrical conductivity and unsatisfactory rate performance. Here we report a facile synthesis of N-doped graphitized hard carbon via a simple carbonization and activation of a urea-soaked self-crosslinked Co-alginate for the high-performance anode of lithium/sodium-ion batteries. Owing to the catalytic graphitization of Co and the introduction of nitrogen-functional groups, the hard carbon shows structural merits of ordered expanded graphitic layers, hierarchical porous channels, and large surface area. Applying in the anode of lithium/sodium-ion batteries, the large surface area and the existence of nitrogen functional groups can improve the specific capacity by surface adsorption and faradic reaction, while the hierarchical porous channels and expanded graphitic layers can provide facilitate pathways for electrolyte and improve the rate performance. In this way, our hard carbon provides its feasibility to serve as an advanced anode material for high-energy rechargeable lithium/sodium-ion batteries.

MXenes, 2D compounds generated from layered bulk materials, have attracted significant attention in energy-related fields. However, most syntheses involve HF, which is highly corrosive and harmful to lithium-ion battery and supercapacitor performance. Here an alkali-assisted hydrothermal method is used to prepare a MXene Ti 3 C 2 T x (T=OH, O). This route is inspired from a Bayer process used in bauxite refining. The process is free of fluorine and yields multilayer Ti 3 C 2 T x with ca. 92 wt % in purity (using 27.5 m NaOH, 270 °C). Without the F terminations, the resulting Ti 3 C 2 T x film electrode (ca. 52 μm in thickness, ca. 1.63 g cm -3 in density) is 314 F g -1 via gravimetric capacitance at 2 mV s -1 in 1 m H 2 SO 4 . This surpasses (by ca. 214 %) that of the multilayer Ti 3 C 2 T x prepared via HF treatments. This fluorine-free method also provides an alkali-etching strategy for exploring new MXenes for which the interlayer amphoteric/acidic atoms from the pristine MAX phase must be removed., (© 2018 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.)

We prepare group VI transitional metal dichalcogenides (TMDs, or MX 2 ) from the 1T phase with quantum-sized and monolayer features via a quasi-full electrochemical process. The resulting two-dimensional (2D) MX 2 (M = W, Mo; X = S, Se) quantum dots (QDs) are ca. 3.0-5.4 nm in size with a high 1T phase fraction of ca. 92%-97%. We attribute this to the high Li content intercalated in the 1T-MX 2 lattice (mole ratio of Li:M is over 2:1), which is achieved by an increased lithiation driving force and a reduced electrochemical lithiation rate (0.001 A/g). The high Li content not only promotes the 2H → 1T phase transition but also generates significant inner stress that facilitates lattice breaking for MX 2 crystals. Because of their high proportion of metallic 1T phase and sufficient active sites induced by the small lateral size, the 2D 1T-MoS 2 QDs show excellent hydrogen evolution reactivity (with a typical η 10 of 92 mV, Tafel slope of 44 mV/dec, and J 0 of 4.16 × 10 -4 A/cm 2 ). This electrochemical route toward 2D QDs might help boost the development of 2D materials in energy-related areas.

Designing materials with a negative feedback function is beneficial for achieving temperature regulation inside a greenhouse. VO 2 has been studied extensively because of its low insulator-to-metal transition temperature (IMT). In this study, reflection changes during a VO 2 phase transition were investigated. Glass fiber cloth was used as a substrate, as it is stable and soft. A VO 2 thin film on a glass fiber cloth whose surface contained 96% V 4+ and 4% V 5+ was prepared using an inorganic sol-gels method. The insulator-to-metal transition temperature was decreased by 38 °C, which was observed from the reflection curve detected using an angle-resolved spectrometer. This decrease in IMT occurred mainly because of the presence of V 5+ , which causes destabilization of the monoclinic phase of VO 2 . When the greenhouse temperature was increased from 30 °C to 40 °C, the reflected intensity of VO 2 on glass fiber cloth decreased by 22% for the wavelength range of 400 nm to 800 nm. In addition, the angle-independent property of the VO 2 thin film was observed using an angle-resolved spectrometer. Owing to its thermo-reflective properties, the thin film can serve as a soft-smart-mirror (SSM) inside a greenhouse to stabilize the temperature, playing a negative feedback role.

Diatomite combined with certain metal-organic frameworks (MOFs) is shown to be an effective CO2 absorbent, although diatomite alone is regarded as inert with respect to CO2 absorption. This finding opens the prospect of reactivating millions of tons of diatomite for CO2 absorption. It also shows for the first time that diatom frustules can act as CO2 buffers, an important link in a successive biological CO2 concentration mechanism chain that impacts on global warming., (© 2013 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.)