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Nb2CTx is a candidate MXene material for lithium-ion batteries because of its advantages in ion movement, diffusion barrier, and average intercalation potentials. However, Nb2CTx nanosheets tend to self-restack when assembled into electrodes because of the strong van der Waals force between them. Electrodes with densely packed Nb2CTx nanosheets can limit the diffusion of Li-ions and impair their electrochemical performance. Here, carbon quantum dots (CQDs) are anchored on the Nb2CTx nanosheets by a hydrothermal reaction to expand the interlayer spacing and create abundant Li-ion transport channels. The CQD-Nb2CTx nanosheets have higher specific surface area (84 m2/g), more active sites, and more Li-ion diffusion paths, which can facilitate the transfer of Li-ions. The CQD-Nb2CTx electrode exhibits a high capacity of 334 mAh/g at 50 mA/g and good long-term cycling stability of 1000 cycles with 260 mAh/g at 1 A/g. [ABSTRACT FROM AUTHOR]

Top-down proteomics is a key mass spectrometry-based technology for comprehensive analysis of proteoforms. Proteoforms exhibit multiple high charge states and isotopic forms in full MS scans. The dissociation behavior of proteoforms in different charge states and subjected to different collision energies is highly variable. The current widely employed data-dependent acquisition (DDA) method selects a narrow m/z range (corresponding to a single proteoform charge state) for dissociation from the most abundant precursors. We describe here Mesh, a novel dissociation strategy, to dissociate multiple charge states of one proteoform with multiple collision energies. We show that the Mesh strategy has the potential to generate fragment ions with improved sequence coverage and improve identification ratios in top-down proteomic analyses of complex samples. The strategy is implemented within an open-source instrument control software program named MetaDrive to perform real time deconvolution and precursor selection. [ABSTRACT FROM AUTHOR]

Targeting selective CO 2 photoreduction into CH 4 remains a challenge due to the sluggish reaction kinetics and poor hydrogenation ability of the unstable intermediate. Here, the active Pt 2+ sites were photodeposited on the SrTiO 3 photocatalyst, which was well demonstrated to manipulate the CH 4 product selectivity. The results showed that SrTiO 3 mainly yielded the CO (6.98 μmol g -1 ) product with poor CH 4 (0.17 μmol g -1 ). With the Pt 2+ modification, 100% CH 4 selectivity could be obtained with an optimized yield rate of 8.07 μmol g -1 . The prominent enhancement resulted from the following roles: (1) the strong electronic interaction between the Pt 2+ cocatalyst and SrTiO 3 could prompt efficient separation of the photoelectron-hole pairs. (2) The Pt 2+ sites were active to capture and activate inert CO 2 into HCO 3- and CO 3 2- species and allowed fast *COOH formation with the lowered reaction barrier. (3) Compared with SrTiO 3 , the formed *CO species could be captured tightly on the Pt 2+ cocatalyst surface for generating the *CH 2 intermediate by the following electron-proton coupling reaction, thus leading to the CH 4 product with 100% selectivity.

The management of wounds remains a significant healthcare challenge, highlighting the need for effective wound healing strategies. To address this, it is crucial to explore the molecular mechanisms underlying tissue repair as well as explore potential therapeutic approaches. Trypsin, as a serine protease, has been clinically utilized for wound healing for decades; however, it still lacks systemic investigation on its role and related mechanism. This study aimed to investigate the effects of low-dose trypsin on wound healing both in vitro and in vivo . While trypsin is an endogenous stimulus for protease-activated receptor 2 (PAR2), we discovered that both low-dose trypsin and synthesized PAR2 agonists significantly enhanced the migration, adhesion, and proliferation of fibroblasts and macrophages, similar to the natural repair mechanism mediated by mast cell tryptase. Moreover, such cell functions induced by trypsin were largely inhibited by PAR2 blockade, indicating the participation of trypsin via PAR2 activation. Additionally, low-dose trypsin notably expedited healing and regeneration while enhancing collagen deposition in skin wounds in vivo. Importantly, upon stimulation of trypsin or PAR2 agonists, there were significant upregulations of genes including claudin-7 (Cldn7), occludin (Ocln), and interleukin-17A (IL-17A) associated with proliferation and migration, extracellular matrix (ECM), tight junction, and focal adhesion, which contributed to wound healing. In summary, our study suggested that a low-dose trypsin could be a promising strategy for wound healing, and its function was highly dependent on PAR2 activation., Competing Interests: The authors declare no competing financial interest., (© 2023 American Chemical Society.)

An ultrathin atomic-layer-deposited (ALD) AlO x gate insulator (GI) was implemented for self-aligned top-gate (SATG) amorphous InGaZnO (a-IGZO) thin-film transistors (TFTs). Although the 4.0-nm thick AlO x exhibited ideal insulating properties, the interaction between ALD AlO x and predeposited a-IGZO caused a relatively defective interface, thus giving rise to hysteresis and bias stress instabilities. As analyzed using high-resolution transmission electron microscopy, X-ray photoelectron spectroscopy, and the Hall measurement, the chemical reaction between the ALD precursor and a-IGZO is revealed. This was effectively prevented by preoxidizing a-IGZO with nitrous oxide (N 2 O) plasma. With 4 nm-AlO x GI and low-defect interfaces, high performance and stability were simultaneously achieved on SATG a-IGZO TFTs, including a near-ideal record-low subthreshold swing of 60.8 mV/dec, a low operation voltage below 0.4 V, a moderate mobility of 13.3 cm 2 /V·s, a low off-current below 10 -13 A, a large on/off ratio over 10 9 , and negligible threshold-voltage shifts less than 0.04 V against various bias-temperature stresses. This work clarifies the vital interfacial reaction between top-gate high- k dielectrics and amorphous oxide semiconductors (AOSs) and further provides a feasible way to remove this obstacle to downscaling SATG AOS TFTs.

The high-grade C 2+ products from CO 2 photoreduction are limited by the kinetic bottleneck. Herein, a multifunctional Au/hydroxide interface was put forward to improve the C-C coupling. As a prototype, the synthesized Au/ZnSn(OH) 6 tuned the CO generation and afforded about 50% electrons toward C 2 H 6 selectivity. The prominent enhancement resulted from the following effects: (1) strong metal-support electronic interactions built an electric field at the interface of ZnSn(OH) 6 nearby the Au nanoparticles, leading to fast transfer of electrons for the C-H and C-C bonding reactions. (2) The surface solid-state Sn-OH and Zn-OH lattice hydroxyls served as donors to feed rich H + and oxygen vacancies (OVs) via hole-induced oxidation for the boosted C 2 H 6 formation. (3) The synergetic OVs and Au sites allowed efficient e - /H + to boost *CO hydrogenation toward *CH 3 and *CH 3 *CH 3 formation into the C 2 H 6 product.

Solid electrolytes (SEs) with superionic conductivity and interfacial stability are highly desirable for stable all-solid-state Li-metal batteries (ASSLMBs). Here, we employ neural network potential to simulate materials composed of Li, Zr/Hf, and Cl using stochastic surface walking method and identify two potential unique layered halide SEs, named Li 2 ZrCl 6 and Li 2 HfCl 6 , for stable ASSLMBs. The predicted halide SEs possess high Li + conductivity and outstanding compatibility with Li metal anodes. We synthesize these SEs and demonstrate their superior stability against Li metal anodes with a record performance of 4000 h of steady lithium plating/stripping. We further fabricate the prototype stable ASSLMBs using these halide SEs without any interfacial modifications, showing small internal cathode/SE resistance (19.48 Ω cm 2 ), high average Coulombic efficiency (∼99.48%), good rate capability (63 mAh g -1 at 1.5 C), and unprecedented cycling stability (87% capacity retention for 70 cycles at 0.5 C).

Antiferroelectric (AFE) materials, featuring an antiparallel alignment of electric dipoles in the adjacent sublattices, are keeping a great promise toward solid-state refrigeration applications on account of their electrocaloric (EC) effects. Although extensive studies have been performed on inorganic oxide counterparts (e.g., PbZrO 3 and AgNbO 3 ), metal-free molecular AFE alternatives with the above-room-temperature EC activities are quite scarce but urgently demanded in terms of environmental issues. Herein, we present a new metal-free molecular AFE, cyclohexylmethylammonium bromide (CMB), which exhibits the unusual antiferroelectric-ferroelectric-paraelectric phase transitions around 364 and 368 K upon heating. The phase transition temperatures are much higher than the majority of known molecular AFE materials. The practical utilization level of electric polarization (∼6 μC/cm 2 ) is clearly evidenced by the typical double polarization-electric field hysteresis loops. Strikingly, large positive and negative EC responses with the temperature changes (Δ T ) of 4.2 and -3 K are achieved under an electric field of 20 kV/cm. The origin of its antiferroelectricity and EC properties is elucidated by the antipolar reorientation of cations along with displacement of bromine anions, being distinct from the known mechanism of inorganic oxides. Such intriguing AFE behaviors, including large polarization and EC effects, reveal great potentials of CMB for the solid-state refrigeration. This study sheds light on further exploration of new AFE candidates toward environmentally friendly solid-state cooling devices.

Graphene-based one-dimensional macroscopic assemblies (GBOMAs) have attracted great attention and extensive efforts have been devoted to enabling great progress. However, their applications are still restricted to less functionalized electronics, and the superior potentials remain scarce. Herein, inspired by natural scallion structure, a novel strategy was introduced to effectively improve battery performances through the mesoscale scallion-like wrapping of graphene. The obtained RGO/Ag-Li anodes demonstrated an ultralow overpotential of ∼11.3 mV for 1800 h at 1 mA cm -2 in carbonate electrolytes, which is superior to those of the most previous reports. Besides, this strategy can also be further expanded to the high mass loading of various cathode nanomaterials, and the resulting RGO/LiFePO 4 cathodes exhibited remarkable rate performance and cycle stability. This work opens a new avenue to explore and broaden the applications of GBOMAs as scaffolds in fabricating full lithium batteries via maximizing their advantages derived from the unique structure and properties.

In this work, we developed an innovative closed bipolar electrode (BPE)-electrochemiluminescence (ECL) sensing strategy with generality for target detection. Based on charge balance and 100% current efficiency between the closed BPE poles and the driving electrodes, one of the driving electrodes in one cell of the closed BPE system was employed as ECL sensing surface to reflect the target on the BPE pole in the opposite cell. Compared with traditional BPE-ECL sensing method, which in general adopted the anodic ECL reagents such as Ru(bpy) 3 2+ and its coreactant on one pole (anode) to reflect the target (occurring reduction reaction) on the other pole (cathode), the difference was that the targets occurring oxidation reaction could be detected by the anodic ECL reagents based on this strategy. To verify the feasibility of this strategy, the detection principle was stated first, and Fe(CN) 6 4- as model target at anodic BPE pole were detected by anodic ECL reagents (Ru(bpy) 3 2+ and TprA) on the driving electrode first. The ECL signals showed good performance for target detection. By changing the size and the material of the BPE pole where the targets were located, the detection of l-ascorbic acid (AA), uric acid (UA), and dopamine (DA) as other model targets with higher detection limit were accomplished. Visual and high-throughput detection of AA, UA, and DA were also successfully realized by an array of the closed BPE system. This closed BPE (array) system is an effective supplement of traditional BPE-ECL sensing and could greatly expand the scope of the detection target.

Currently, developing high voltage (beyond 2 V) rechargeable Mg-ion batteries still remains a great challenge owing to the limit of corrosive electrolyte and low compatibility of anode material. Here we report a facile one step solid state alloying route to synthesize nanoclustered Mg 3 Bi 2 alloy as a high-performance anode to build up a 2 V Mg-ion battery using noncorrosive electrolyte. The fabricated nanoclustered Mg 3 Bi 2 anode delivers a high reversible specific capacity (360 mAh g -1 ) with excellent stability (90.7% capacity retention over 200 cycles) and high Coulombic efficiency (average 98%) at 0.1 A g -1 . The good performance is attributed to the stable nanostructures, which effectively accommodate the reversible Mg 2+ ion insertion/deinsertion without losing electric contact among clusters. Significantly, the nanoclustered Mg 3 Bi 2 anode can be coupled with high voltage cathode Prussian Blue to assemble a full cell using noncorrosive electrolyte, showing a stable cycling (88% capacity retention over 200 cycles at 0.2 A g -1 ) and good rate capability (103 mAh g -1 at 0.1 A g -1 and 58 mAh g -1 at 2 A g -1 ). The energy and power density of the as-fabricated full cell can reach up to 81 Wh kg -1 and 2850 W kg -1 , respectively, which are both the highest values among the reported Mg-ion batteries using noncorrosive electrolytes. This study demonstrates a cost-effective route to fabricate stable and high voltage rechargeable Mg-ion battery potentially for grid-scale energy storage.

Engineering biomaterials to manipulate the immune response to elicit specific therapeutic outcomes is a burgeoning field of research. Mast cells play a distinct and central role in the innate immune response, and are characterized by their rapid release of a myriad of proinflammatory mediators in response to stimulation. These mediators are central to protective actions such as wound healing, angiogenesis, and host defense against pathogens and animal venoms. Considering that mast cells are widely distributed in tissues that interface with the external environment, and are loaded with large amounts of preformed protective compounds, they are ideal targets for novel immunotherapies. Here we report that, by using an engineered nanoscaffold, human mast cells can be contact activated in cell and primary human skin tissue culture using a specific receptor-ligand mechanism. The IgE independent PAMP-12 peptide activates human mast cells through the recently identified Mas-related G-protein coupled receptor member X2 (MRGPRX 2 ) receptor. The PAMP-12 motif was conjugated, via a glycine spacer, with the self-assembling peptide (RADA) 4 and mixed with unmodified (RADA) 4 to form a nanofiber matrix; mast cell activation was influenced directly by this ratio. Moreover, conjugating the PAMP-12 motif within the matrix was shown to only activate local, tissue-resident mast cells. The result of ex vivo human skin tissue tests confirmed that the engineered nanoscaffold successfully activated skin-resident mast cells by contact. Thus, this nanoscaffold design may provide a new platform to modulate localized mast cell functions thereby facilitating their protective role in the skin.

Lithium sulfur (Li-S) batteries are considered as promising energy storage systems for the next generation of batteries due to their high theoretical energy densities and low cost. Much effort has been made to improve the practical energy densities and cycling stability of Li-S batteries via diverse designs of materials nanostructure. However, achieving simultaneously good rate capabilities and stable cycling of Li-S batteries is still challenging. Herein, we propose a strategy to utilize a dual effect of metal carbide nanoparticles decorated on carbon nanofibers (MC NPs-CNFs) to realize high rate performance, low hysteresis, and long cycling stability of Li-S batteries in one system. The adsorption experiments of lithium polysulfides (LiPS) to MC NPs and corresponding theoretical calculations demonstrate that LiPS are likely to be adsorbed and diffused on the surface of MC NPs because of their moderate chemical bonding. MC NPs turn out to have also an electrocatalytic role and accelerate electrochemical redox reactions of LiPS, as proven by cyclic voltammetry analysis. The fabricated Li-S batteries based on the W 2 C NPs-CNFs hybrid electrodes display not only high specific capacity of 1200 mAh/g at 0.2C but also excellent rate performance and cycling stability, for example, a model setup can be operated at 1C for 500 cycles maintaining a final specific capacity of 605 mAh/g with a degradation rate as low as 0.06%/cycle.

A new type of Cp*Ir complex bearing a functional 2,2'-bibenzimidazole ligand was designed, synthesized, and found to be a highly effective and general catalyst for the N-methylation of a variety of amines with methanol in the presence of a weak base (0.3 equiv of Cs 2 CO 3 ).

Separators, necessary components to isolate cathodes and anodes in Li/Na-ion batteries, are consumed in large amounts per year; thus, their sustainability is a concerning issue for renewable energy storage systems. However, the eco-efficient and environmentally friendly fabrication of separators with a high mechanical strength, excellent thermal stability, and good electrolyte wettability is still challenging. Herein, we reported the fabrication of a new type of separators for Li/Na-ion batteries through the self-assembly of eco-friendly chitin nanofibers derived from prawn shells. We demonstrated that the pore size in the chitin nanofiber membrane (CNM) separator can be tuned by adjusting the amount of pore generation agent (sodium dihydrogen citrate) in the self-assembly process of chitin nanofibers. By optimizing the pore size in CNM separators, the electrochemical performance of the LiFePO 4 /Li half-cell with a CNM separator is comparable to that with a commercialized polypropylene (PP) separator. More attractively, the CNM separator showed a much better performance in the LiFePO 4 /Li cell at 120 °C and Na 3 V 2 (PO 4 ) 3 /Na cell than the PP separator. The proposed fabrication of separators by using natural raw materials will play a significant contribution to the sustainable development of renewable energy storage systems.

A cyclometalated iridium(III) complex containing a N ∧ C ∧ N-coordinating terdentate ligand [Ir(dpyx-N,C,N)Cl(μ-Cl)] 2 was found to be a general and highly effective catalyst for the α-alkylation of ketones and N-alkylation of amines with alcohols. In the presence of catalyst (1 mol % Ir) and base (0.2-0.5 equiv), a variety of desirable products were obtained in good yields under an air atmosphere. Notably, this research exhibited the new potential of Ir(III) complexes bearing non-Cp* ligand and will facilitate the progress of the hydrogen autotransfer process.

Lithium metal is one of the most attractive anode materials for next-generation lithium batteries due to its high specific capacity and low electrochemical potential. However, the poor cycling performance and serious safety hazards, caused by the growth of dendritic and mossy lithium, has long hindered the application of lithium metal based batteries. Herein, we reported a rational design of free-standing Cu nanowire (CuNW) network to suppress the growth of dendritic lithium via accommodating the lithium metal in three-dimensional (3D) nanostructures. We demonstrated that as high as 7.5 mA h cm(-2) of lithium can be plated into the free-standing copper nanowire (CuNW) current collector without the growth of dendritic lithium. The lithium metal anode based on the CuNW exhibited high Coulombic efficiency (average 98.6% during 200 cycles) and outstanding rate performance owing to the suppression of lithium dendrite growth and high conductivity of CuNW network. Our results demonstrate that the rational nanostructural design of current collector could be a promising strategy to improve the performance of lithium metal anode enabling its application in next-generation lithium-metal based batteries.

A strategy for the synthesis of quinazolinones via acceptorless coupling of o-aminobenzamides with methanol has been accomplished in the presence of the metal-ligand bifunctional catalyst [Cp*Ir(2,2'-bpyO)(H2O)]. Notably, this research exhibited the potential of transition-metal-catalyzed activation of methanol as a C1 source for the construction of heterocycles.