A plasmonic photocatalyst Ag-AgI supported on mesoporous alumina (Ag-AgI/Al(2)O(3)) was prepared by deposition-precipitation and photoreduction methods. The catalyst showed high and stable photocatalytic activity for the degradation and mineralization of toxic persistent organic pollutants, as demonstrated with 2-chlorophenol (2-CP), 2,4-dichlorophenol (2,4-DCP), and trichlorophenol (TCP) under visible light or simulated solar light irradiation. On the basis of electron spin resonance, cyclic voltammetry analyses under a variety of experimental conditions, two electron transfer processes were verified from the excited Ag NPs to AgI and from 2-CP to the Ag NPs, and the main active species of O(2)(*-) and excited h(+) on Ag NPs were involved in the photoreaction system of Ag-AgI/Al(2)O(3). A plasmon-induced photocatalytic mechanism was proposed. Accordingly, the plasmon-induced electron transfer processes elucidated the photostability of Ag-AgI/Al(2)O(3). This finding indicates that the high photosensitivity of noble metal NPs due to surface plasmon resonance could be applied toward the development of new plasmonic visible-light-sensitive photocatalysts and photovoltaic fuel cells.

Bismuth (Bi) is an attractive material as anodes for both sodium-ion batteries (NIBs) and potassium-ion batteries (KIBs), because it has a high theoretical gravimetric capacity (386 mAh g −1 ) and high volumetric capacity (3800 mAh L −1 ). The main challenges associated with Bi anodes are structural degradation and instability of the solid electrolyte interphase (SEI) resulting from the huge volume change during charge/discharge. Here, a multicore-shell structured Bi@N-doped carbon (Bi@N-C) anode is designed that addresses these issues. The nanosized Bi spheres are encapsulated by a conductive porous N-doped carbon shell that not only prevents the volume expansion during charge/discharge but also constructs a stable SEI during cycling. The Bi@N-C exhibits unprecedented rate capability and long cycle life for both NIBs (235 mAh g −1 after 2000 cycles at 10 A g −1 ) and KIBs (152 mAh g −1 at 100 A g −1 ). The kinetic analysis reveals the outstanding electrochemical performance can be attributed to significant pseudocapacitance behavior upon cycling.

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The biggest challenge of potassium-ion batteries (KIBs) application is to develop high-performance electrode materials to accommodate the potassium ions large size. Herein, by rational design, we carbonize three-dimensional (3D) ordered macroporous ZIF-8 to fabricate 3D interconnected nitrogen-doped hierarchical porous carbon (N-HPC) that shows excellent rate performance (94 mAh g −1 at 10.0 A g −1 ), unprecedented cycle stability (157 mA g −1 after 12000 cycles at 2.0 A g −1 ), and superior reversible capacity (292 mAh g −1 at 0.1 A g −1 ). The 3D hierarchical porous structure diminishes the diffusion distance for both ions/electrons, while N-doping improves the reactivity and electronic conductivity via producing more defects. In addition, the bicontinuous structure possesses a large specific surface area, decreasing the current density, again improving the rate performance. In situ Raman spectra analysis confirms the potassiation and depotassiation in the N-HPC are highly reversible processes. The galvanostatic intermittent titration measurement and first-principles calculations reveal that the interconnected macropores are more beneficial to the diffusion of the K + . This 3D interpenetrating structure demonstrates a superiority for energy storage applications.

Biodegradable synthetic scaffolds hold great promise for oral and craniofacial guided tissue regeneration and bone regeneration. To overcome the limitations of current scaffold materials in terms of osteogenic and antimicrobial properties, we have developed a novel silver-modified/ collagen-coated electrospun PLGA/PCL scaffold (PP-pDA-Ag-COL) with improved antimicrobial and osteogenic properties. Our novel scaffold was generated by electrospinning a basic PLGA/PCL matrix, followed by silver nanoparticle (AgNPs) impregnation via in situ reduction and polydopamine coating, and then coated by collagen I. The three intermediate materials involved in the fabrication of our scaffolds, PLGA/PCL (PP), PLGA/PCL-polydopamine (PP-pDA), and PLGA/PCL-polydopamine-Ag (PP-pDA-Ag) were used as control scaffolds. Scanning electron micrographs and mechanical testing indicated that the unique 3-dimensional structures with randomly-oriented nanofibrous electrospun-scaffold architectures, the elasticity modulus and the tensile strength were maintained after modifications. CCK-8 cell proliferation analysis demonstrated that the PP-pDA-Ag-COL scaffold was associated with higher MC3T3 proliferation rates than the three control scaffolds employed. Scanning electron and fluorescence light microscopy illustrated that PP-pDA-Ag-COL scaffolds significantly enhanced MC3T3 cell

To meet the requirements of the rapid development of large-scale energy storage systems, "Beyond Li-ion battery (LIB)" systems are attracting more and more attention. [1][2][3][4][5] Among various alkali metals ion batteries, potassium-ion batteries (KIBs) exhibit many advantages for large-scale energy storage system applications including: [6,7] 1) the low manufacturing costs because of the natural abundance of their raw materials; 2) much lower redox potential of K/K + (−2.93 V vs standard hydrogen electrode) leading to higher open-circuit voltage and higher energy density compared with sodiumion batteries (SIBs). [8][9][10] According to the advantages and properties of low production costs and high energy density, the KIB is considered as a promising energy storage system for large-scale energy storage application. However, KIBs suffer from inferior cyclic stability and insufficient power density resulting from the structure collapse of electrode materials due to the bigger K + Constructing 2D heterostructure materials by stacking different 2D materials can combine the merits of the individual building blocks while eliminating their shortcomings. Dichalcogenides are attractive anodes for potassium-ion batteries (KIBs) due to their high theoretical capacity. However, the practical application of dichalcogenide is greatly hampered by the poor electrochemical performance due to sluggish kinetics of K + insertion and the electrode structure collapse resulting from the large K + insertion. Herein, heterostructures of 2D molybdenum dichalcogenide on 2D nitrogen-doped carbon (MoS 2 , MoSe 2 -on-NC) are prepared to boost their potassium storage performance. The unique 2D heterostructures possess built-in heterointerfaces, facilitating K + diffusion. The robust chemical bonds (CS, CSe, CMo bonds) enhance the mechanical strength of electrodes, thus suppressing the volume expansion. The 2D N-doped carbon nanosheets interconnected as a 3D structure offer a fast diffusion path for electrons. Benefitting from these merits, both the MoS 2 -on-NC and the MoSe 2 -on-NC exhibit unprecedented cycle life. Moreover, the electrochemical reaction mechanism of MoSe 2 is revealed during the process of potassiation and depotassiation.The ORCID identification number(s) for the author(s) of this article can be found under https://doi.

Sodium‐ion batteries (NIBs) have attracted more and more attention as economic alternatives for lithium‐ion batteries (LIBs). Sodium super ionic conductor (NASICON) structure materials, known for high conductivity and chemical diffusion coefficient of Na+ (≈10−14 cm2 s−1), are promising electrode materials for NIBs. However, NASICON structure materials often suffer from low electrical conductivity (<10−4 S cm−1), which hinders their electrochemical performance. Here high performance sodium storage performance in Na3V2(PO4)3 (NVP) is realized by optimizing nanostructure and rational surface engineering. A N, B codoped carbon coated three‐dimensional (3D) flower‐like Na3V2(PO4)3 composite (NVP@C‐BN) is designed to enable fast ions/electrons transport, high‐surface controlled energy storage, long‐term structural integrity, and high‐rate cycling. The conductive 3D interconnected porous structure of NVP@C‐BN greatly releases mechanical stress from Na+ extraction/insertion. In addition, extrinsic defects and active sites introduced by the codoping heteroatoms (N, B) both enhance Na+ and e− diffusion. The NVP@C‐BN displays excellent electrochemical performance as the cathode, delivering reversible capacity of 70% theoretical capacity at 100 C after 2000 cycles. When used as anode, the NVP@C‐BN also shows super long cycle life (38 mA h g−1 at 20 C after 5000 cycles). The design provides a novel approach to open up possibilities for designing high‐power NIBs.

AgBr coated with silver (Ag) nanoparticles (NPs) were highly dispersed on ordered mesoporous γ-Al 2 O 3 (MA) by the deposition-precipitation method with surfactant (Ag-AgBr/MAP). The catalyst showed high and stable photocatalytic activity for the degradation and mineralization of toxic persistent organic pollutants, as demonstrated with 2-chlorophenol (2-CP), 2,4-dichlorophenol, and trichlorophenol under visible light or simulated solar light irradiation. The dispersion of Ag-AgBr NPs on MA strongly affected their photoactivity. On the basis of electron spin resonance and cyclic voltammetry analyses under a variety of experimental conditions, two plasmon-induced electron-transfer processes were verified from the excited Ag NPs to AgBr and from 2-CP to the Ag NPs, resulting in O 2• •-radicals were primary active species, whereas the excited h + on Ag NPs was involved in the photoreaction system of Ag-AgBr/MAP. The highly efficient degradation of pollutants came from both photoexcited AgBr and plasmon-excited Ag NPs. Accordingly, the plasmoninduced electron-transfer processes elucidated the photostability of Ag-AgBr/MAP. These findings indicate potential applications of noble metal NPs in the fields of developing visible-light-sensitive photocatalysts and photovoltaic fuel cells.