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To realize the practical applications of the next-generation lithium-metal batteries (LMBs), it is critical to developing high-areal-capacity lithium (Li) anodes with high reversibility and dendrite-free electrodeposition. Herein, we demonstrate a “dendrite-eating” strategy to enable high-areal-capacity LMBs by introducing silicon (Si) coating onto the polypropylene (PP) separator. The Si layer is found to be effective in stabilizing the Li electrodeposition and reduce the Li loss. The in-situ optical cell observation and electrochemical characterizations reveal that the “dendrite-eating” coating serves as both a Li absorbant to suppress (“eat”) the dendrites growth and a backup Li reservoir to replenish the Li loss. With this “dendrite-eating” separator, the Li consumption during cycling is reduced by 66%, and the cyclability and reversibility of the Li anodes are also significantly improved, leading to a prolonged stripping/plating lifetime for >1000 ​h and high Coulombic efficiency (CE) of >97.6% in carbonate electrolyte. Coupled with an industry-level high-loading LiFePO4 cathode (20.0 ​mg ​cm−2), a thin Si coating of only 0.2 ​mg ​cm−2 on the separator remarkably improves the full-cell cycling stability.

Porous Li3V2(PO4)3 frameworks have been synthesized via a simple hydrothermal route along with subsequent calcination. Polyethylene glycol (PEG-400) is employed as a soft template to control the morphology of the products. The porous frameworks consist of abundant Li3V2(PO4)3 nanowires which cross with each other to form a 3D network structure. Benefiting from the intriguing hierarchical structure, the unique Li3V2(PO4)3 electrodes exhibit excellent rate capability and good cyclability (96% of the initial discharge capacity retained after 500 cycles) in a voltage range of 3.0–4.3 V.

SUMMARYAndrogen deprivation therapy (ADT) induces regression of recurrent and advanced prostate cancer (PrCa), but many tumors recur. To understand the response to ADT, changes in tumor volume were imaged after castration of murine PrCa models. While mouse (non-tumor) prostate begins to regress within two days of castration, murine PrCa regresses after a delay of 3-14 days in two distinct mouse models. Intra-tumoral androgens are undetectable after castration, but tumor cells proliferate during this period. Intratumoral glucocorticoids and glucocorticoid receptor (GR) protein increase, as does GR mRNA and a set of GR-regulated genes specifically in tumor epithelial cells identified using scRNAseq. A selective GR antagonist (CORT125281, relacorilant), in clinical trials for late-state PrCa, eliminates the delayed regression phenotype in both models. Thus, activated GR signaling and murine tumor proliferation following castration resembles the GR-dependent escape mechanism of castrate resistant PrCa. These results suggest simultaneous inhibition of GR and androgen receptor signaling could improve PrCa therapy.In briefAndrogen deprivation therapy for high risk and recurrent prostate cancers is initially effective, but ultimately fails; better understanding the mechanisms should improve therapy. In two murine prostate cancer models, GR signaling is activated immediately following castration, substituting for the acute reduction in AR signaling, and allowing for continued tumor growth. This continued growth is blocked by relacorilant, selective GR antagonist in clinical trials for late-state PrCa.HighlightsAndrogen deprivation therapy induces regression of prostate cancer, but tumors recurMurine PrCa continues to proliferate for 3-14 days in two distinct mouse prostate cancer modelsTumor cells proliferate during this period, and intratumoral glucocorticoids and glucocorticoid receptor (GR) protein increase, as does GR mRNA and a set of GR-regulated genesRelacorilant, a selective GR antagonist in clinical trials for late-state PrCa, eliminates the delayed regression

Na3V2(PO4)3 (NVP) has been considered as a promising cathode for its high operating voltage and large capacity, though it suffers from an inherent low electronic conductivity and Na+ ion mobility. ...

Sodium layered transition metal oxides have been considered as promising cathode materials for sodium ion batteries due to their large capacity and high operating voltage. However, mechanism invest...

MOF(Ni/Fe) nanosheets were grown in situ vertically on three-dimensional (3D) nickel foam (NF). To induce a chemical coupling effect, defective CeO2-x nanoparticles (NPs) were chemically decorated on the surfaces of the MOF(Ni/Fe)/NF nanosheets. This phenomenon confirmed a positive effect for oxygen evolution in alkaline medium. The oxygen evolution reaction (OER) performance of the electrocatalysts reached an overpotential of ∼254 mV at j = 50 mA cm−2 with a Tafel slope of ∼34 mV dec−1.

Molybdenum oxide (MoO2) has been considered as a promising anode material in lithium-ion batteries with high theoretical capacity (838 mAh/g); regrettably, the drawback of rapid capacity decay seriously hinders its application. In this work, MoO2 nanoparticles were in situ encapsulated inside the frameworks of porous carbon to construct MoO2-carbon nanocomposites by a facile triconstituent co-assembly approach. The obtained MoO2-carbon nanocomposites present stable structures and exhibit improved electrochemical performances of high reversible capacity (803 mAh/g at 0.1 A/g) and excellent cycling stability (572 mAh/g at 1 A/g after 400 cycles) as anode materials for lithium-ion batteries. These satisfactory results are mainly attributed to the synergy effects between the MoO2 nanoparticles and carbon frameworks, specifically a better accommodation of volume change and a shorter pathway for ion transmission.

A novel heterostructured Si@C@Ge anode is developed via a two-step sol–gel method. A facile and straightforward Ge decoration significantly boosts the Li-storage performance of core–shell Si@C nanoparticles on both mechanics and kinetics. The Si@C@Ge anode shows unprecedented electrochemical performance in terms of accessible capacity, cycling stability, and rate capability when compared to those of a core–shell Si@C anode. Based on the experimental results and analysis of the mechanism, it is evident that high-conductivity Ge nanograins on the surface facilitates the Li diffusivity and electron transport and guarantees high ion accessibility. Moreover, it is the Ge nanograins that serve as buffering cushion to tolerate the mechanic strain distribution on the electrode during lithiation/delithiation processes.

The removal of chloride from simulated zinc sulfate electrolyte by ozone oxidation was investigated. The effects of various process factors including the O2 flow, bubbling time, reaction temperature, H2SO4 and ZnSO4 concentration, and existence of Mn2 + were systematically studied. The results showed that with increasing O2 flow, the chloride removal increased first and then decreased. Increasing both the bubbling time and reaction temperature was beneficial to dechlorination while an increase in the ZnSO4 concentration had an adverse effect. With increasing sulfuric acid concentration, the dechlorination rapidly rose due to the increasing hydrogen ion concentration in electrolyte. Optimum dechlorination process conditions in the absence of Mn2 + were obtained as follows: O2 flow 0.4 L·min− 1, H2SO4 concentration 160 g·L− 1, Zn2 + concentration 40 g·L− 1, reaction temperature 70 °C, and reaction time 120 min. Under these conditions, the concentration of Cl− was reduced from 300 to 5 mg·L− 1. The existence of Mn2 + can further accelerate the reaction of ozone with chloride, which was probably through charge-transfer and coordination catalysis mechanism.

In this work, we have prepared several kinds of potassium salts doped Ru/AC catalysts and systematically studied their catalytic activities towards water–gas shift (WGS) reaction. Activity testing indicated that K 2 CO 3 doped Ru/AC catalyst (Ru-K 2 CO 3 /AC) showed higher catalytic performance than KOH and KOAc doped Ru/AC catalysts, methane selectivity decreased most after doping KOH. Although the particle size of Ru nanoparticles in Ru-K 2 CO 3 /AC catalyst was larger than that of the parent Ru/AC catalyst, H 2 -TPR indicated that RuO x was reduced at much lower temperature, suggesting a weaker interaction between RuO x and the surface functional group of active carbon after the doping of K 2 CO 3 . Thus, Ru nanoparticles interacted stronger with the reaction molecules (CO and H 2 O), leading a higher catalytic activity. In addition, the doping of K 2 CO 3 on the surface of Ru/AC catalyst also increased the concentration of water around Ru active site due to the hygroscopic ability. Interestingly, it was also found that the prepared method also greatly affected the catalyst activity. If the active carbon was firstly coated with K 2 CO 3 , followed deposition of Ru metal nanoparticles, (called Ru/K 2 CO 3 -AC catalyst), the activity decreased remarkably as compared to Ru-K 2 CO 3 /AC. The low catalytic activity of Ru/K 2 CO 3 -AC was mainly due to the aggregation of Ru nanoparticles.

Arsenic trioxide (ATO), an FDA-approved drug for acute promyelocytic leukemia, also has great potential for treatment of solid tumors. Drug delivery powered by recent advances in nanotechnology has boosted the efficacy of many drugs, which is enlightening for applications of ATO in treating solid tumors. Herein, we reported arsenite-loaded multifunctional nanoparticles that are capable of pH-responsive ATO release for treating hepatocellular carcinoma (HCC) and real-time monitoring via magnetic resonance imaging. We fabricated these nanoparticles (designated as magnetic large-pore mesoporous silica nanoparticle (M-LPMSN)-NiAsO x ) by loading nanoparticulate ATO prodrugs (NiAsO x ) into the pores of large-pore mesoporous silica nanoparticles (LPMSNs) that contain magnetic iron oxide nanoparticles in the center. The surface of these nanodrugs was modified with a targeting ligand folic acid (FA) to further enhance the drug efficacy. Releasing profiles manifest the responsive discharging of arsenite in acidic environment. In vitro experiments with SMMC-7721 cells reveal that M-LPMSN-NiAsO x -FA nanodrugs have significantly higher cytotoxicity than traditional free ATO and induce more cell apoptosis. In vivo experiments with mice bearing H22 tumors further confirm the superior antitumor efficacy of M-LPMSN-NiAsO x -FA over traditional free ATO and demonstrate the outstanding imaging ability of M-LPMSN-NiAsO x -FA for real-time tumor monitoring. These targeted arsenite-loaded magnetic mesoporous silica nanoparticles integrating imaging and therapy hold great promise for treatment of HCC, indicating the auspicious potential of LPMSN-based nanoplatforms.

Silicon as an electrode suffers from short cycling life, as well as unsatisfactory rate-capability caused by the large volume expansion (~400%) and the consequent structural degradation during lithiation/delithiation processes. Here, we have engineered unique void-containing mesoporous carbon-encapsulated commercial silicon nanoparticles (NPs) in yolk-shell structures. In this design, the silicon NPs yolk are wrapped into open and accessible mesoporous carbon shells, the void space between yolk and shell provides enough room for Si expansion, meanwhile, the porosity of carbon shell enables fast transport of Li + ions between electrolyte and silicon. Our ex-situ characterization clearly reveals for the first time that a favorable homogeneous and compact solid electrolyte interphase (SEI) film is formed along the mesoporous carbon shells. As a result, such yolk-shell Si@mesoporous-carbon nanoparticles with a large void exhibits long cycling stability (78.6% capacity retention as long as 400 cycles), and superior rate-capability (62.3% capacity retention at a very high current density of 8.4 A g −1 ).

Here, we report the synthesis of reduced graphene oxide@mesoporous silica (denoted as rGO@mSiO2) sandwich-like sheets by an oil–water biphase stratification approach. The resultant rGO@mSiO2 nanosheets possess a uniform sandwich-like structure, ultrathin thickness (∼50 nm), large aspect ratio, high surface area (∼755 m2/g), and enlarged and tunable pore size (from 2.8 to 8.9 nm). Significantly, the mesochannels are oriented perpendicularly to graphene surfaces and shaped like a funnel, which facilitates drug loading and releasing. The influences of the concentration of precursor, solvent, GO sheet, and reaction temperature on the formation of the sandwich-like rGO@mSiO2 nanosheets have been systematically investigated. The resultant nanosheets with a pore size of ∼8.9 nm show the maximum loading capacity of bovine β-lactoglobulin (55.1 wt %). The protein releasing process in the simulated body fluid suggests that the release can be controlled from 20 to 60 h simply by adjusting the pore size. In addition,...

Nitrogen-doped ordered mesoporous carbons (N-doped OMCs) with a high surface area of 1741 m 2 /g and nitrogen content up to 15 wt.% have been synthesized by nanocasting approach by using SBA-15 as a hard template, phenolic resin (resol) as a carbon source and high nitrogen-containing cyanamide as the nitrogen dopant. The introduction of cyanamide not only incorporates high-content nitrogen into the carbon matrix in the primary forms of pyridinic and quaternary species, but also greatly increases the surface area of materials. The obtained N-doped OMCs have large surface area with mesoporosity up to 92%, uniform and appropriate pore size (3.6–4.1 nm), large pore volume (1.2–1.81 cm 3 /g). These merits together with high nitrogen enrichment lead to a specific capacitance (230 F/g at 0.5 A/g) and good rate capability (175 F/g at 20 A/g with capacitance retention of 77.4%) in 6 M KOH aqueous electrolytes.

A magnesiothermic reduction approach is designed to synthesize mesoporous Si/C nanocomposites with ultrasmall, uniform silicon nanoparticles (ca. 3 nm) embedded in a rigid mesoporous carbon framework. The resultant mesoporous Si/C nanocomposites present excellent performance with high reversible capacity, good Coulombic efficiency and rate capability, and outstanding cycling stability in lithium-ion battery applications.

Novel carbon nanomaterials have aroused significant interest owing to their prospects in various technological applications. The recently developed on-surface synthesis strategy provides a route toward atomically precise fabrication of nanostructures, which paves the way to functional molecular nanostructures in a controlled fashion. A plethora of low-dimensional nanostructures, challenging to traditional solution chemistry, have been recently fabricated. Within the last few decades, an increasing interest and flourishing studies on the fabrication of novel low-dimensional carbon nanostructures using on-surface synthesis strategies have been witnessed. In particular, carbon materials, including fullerene, carbon nanotubes, and graphene nanoribbons, are synthesized with atomic precision by such bottom-up methods. Herein, starting from the basic concepts and progress made in the field of on-surface synthesis, the recent developments of atomically precise fabrication of low-dimensional carbon nanostructures are reviewed.

Three-dimensional (3-D) macroporous structures with a short-range order of pore arrangements are of both scientific significance and consequent technological impact. Inspired by parrot feather barbs that display a bright blue structural color, artificial 3-D macroporous SiO2 and TiO2 structures were successfully fabricated by using the barbs as templates. Structural and optical characterization show that the fabricated structures are 3-D bi-continuous macroporous structures with short-range order and display bright structural colors.

In this paper, we report a simple melt impregnation method by using cheap mesophase pitches (MPs) as carbon precursors to prepare ordered mesoporous carbon with ordered graphitized pore walls at low temperature. This facile procedure includes melting MPs at 140 °C and impregnation of the melt into hexagonal or bicontinuous cubic mesoporous silica templates. After the removal of silica templates by HF solution, ordered mesoporous carbon materials with replica structures of 2-D hexagonal p6mm or cubic Ia3d symmetry were derived. The pore walls of the hexagonal mesoporous carbon products are composed of graphitized domains with the (002) crystallographic plane of the graphite perpendicular to the long axis of the carbon nanorods. Theoretical computations show that negatively charged O atoms of Si−OH and Si−O−Si from the surface of mesoporous silica channels can interact with the positive charged H atoms of the MPs, which makes the stacking units incorporate into the pores with the (002) plane vertical to th...

Cyclometalated platinum(II) complex has been successfully incorporated into the (3-aminopropyl) triethoxysilane-modified channels of ordered mesoporous silica SBA-15 that has large pore hexagonal channels. Studies on the (1)O(2) generation conclusively demonstrates that the olefins in the nano-channels of SBA-15 can be enriched 8 times higher than those in the homogeneous solution as the diffusion quantum yield of singlet oxygen ((1)O(2)) is assumed to be unit. The platinum(II) complex loaded in the channel of SBA-15 is stable, and the photosensitized oxidation occurs efficiently. No obvious degradation and leaching of photosensitizers is observed even after 10 runs. Only a simple filtration is needed for the recycled use of the expensive noble metal catalysts. This versatile system is a good example of photochemical reactions occurring in the mesoporous silica molecular sieve. SBA-15 not only provides a support for the photosensitizer, but also acts as a nano-reactor to facilitate the photooxidation.