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Safety and high energy density have long restricted the large-scale practical application of lithium metal batteries because of the unbridled growth of lithium dendrites and the rapid deteriorating cycle performance of the LiNi0.8Co0.1Mn0.1O2 (NCM811) cathode. Herein, an additive of RbNO3 with multiple functions is proposed for dendrite-free NCM811 lithium metal batteries. Benefiting from the electrostatic shielding effect formed by Rb+ during the Li+ deposition process and the solvation effect of NO3- to regulate lithium deposition, a high Coulombic efficiency of 95.02% (compared with the low Coulombic efficiency of 89.37% in the blank electrolyte) is acquired in Li//Cu cells, and the uniform growth of the lithium metal deposition with a large strawberry-like morphology is achieved. Moreover, when a cathode of NCM811 matches with a lithium metal anode, an extraordinary capacity retention of 93.67% after 200 cycles with a high Coulombic efficiency of 99.7% in the electrolyte with the RbNO3 system (a capacity retention of 80.1% with a Coulombic efficiency of 98.0% for the blank electrolyte) is achieved at 1C. This work provides guidance for the development of high-efficiency additives with dual synergistic regulation effects of anions and cations for lithium metal batteries in the future.

Multiplexed intracellular detection is desirable in biomedical sciences for its higher efficiency and accuracy compared to the single-analyte detection. However, it is very challenging to construct nanoprobes that possess multiple fluorescent signals to recognize the different intracellular species synchronously. Herein, we proposed a novel dual-excitation/dual-emission upconversion strategy for multiplexed detection through the design of upconversion nanoparticles (UCNP) loaded with two dyes for sensitization and quenching of the upconversion luminescence (UCL), respectively. Based on the two independent energy transfer processes of near-infrared (NIR) dye IR845 to UCNP and UCNP to visible dye PAPS-Zn, ClO− and Zn2+ were simultaneously detected with a limit of detection (LOD) of 41.4 and 10.5 nM, respectively. By utilizing a purpose-built 830/980 nm dual-laser confocal microscope, both intrinsic and exogenous ClO− and Zn2+ in live MCF-7 cells have been accurately quantified. Such dual-excitation/dual-emission ratiometric UCL detection mode enables not only monitoring multiple intracellular analytes but also eliminating the detection deviation caused by inhomogeneous probe distribution in cells. Through modulation of NIR dye and visible dye with other reactive groups, the nanoprobes can be extended to analyze various intracellular species, which provides a promising tool to study the biological activities in live cells and diagnose diseases.

Metal-organic frameworks (MOFs), a unique type of porous material characterized by high porosity, large internal surface area and remarkable structural tunability, have emerged as very attractive functional materials for a variety of applications. As a promising subclass of MOFs, lanthanide metal-organic frameworks (Ln-MOFs) integrate the unique advantages of MOFs and the intrinsic features of lanthanide ions, such as sharp emission bands, long luminescent lifetimes, large Stokes shifts, high color purity and high resistance to photobleaching. In this minireview, we provide a brief overview of the most recent advances in luminescent Ln-MOF nanoprobes, which covers from their chemical and physical fundamentals to bioapplications, including their synthetic strategies, optical properties and promising bioapplications in biodetection, bioimaging and therapy. Finally, some of the most important emerging trends and future efforts toward this rapidly evolving field are also envisioned.

The metal halide perovskite quantum dots (APbX3 PeQDs; A = Cs or CH3NH3; X = Cl, Br or I) have emerged as a new type of promising optoelectronic material for light-emitting and photovoltaic applications because of their excellent optical properties. However, the precise control over the size and photoluminescence (PL) emission of APbX3 PeQDs remains a great challenge, which has been one of the main obstacles to the applications of PeQDs. Herein, we report a unique strategy for in situ confined growth of MAPbBr3 (MA = CH3NH3) PeQDs by using porous metal-organic framework (MOF) UiO-66 as a matrix. By introducing Pb(Ac)2 and MABr precursors into the pores of UiO-66 via a stepwise approach, ultrasmall MAPbBr3 PeQDs were in situ grown in the matrix with the size tuned from 6.4 to 3.3 nm by changing the concentration of the Pb(Ac)2 precursor. Accordingly, the PL emission wavelength of the resulting MAPbBr3 PeQDs was blue-shifted from 521 to 486 nm with the size reduction, owing to the strong quantum confinement effect of the PeQDs. Due to the surface passivation effect endowed by the UiO-66 matrix, the ultrasmall MAPbBr3 PeQDs also displayed a high PL quantum yield (PLQY) of 43.3% and a long PL lifetime of 100.3 ns. This study proposes a new strategy to prepare ultrasmall PeQDs and effectively control their sizes and PL emissions, which may open up new avenues for the development of high-performance luminescent PeQDs for diverse applications.

Acute myocardial infarction (AMI) is one of the leading causes of death around the world. An early and accurate diagnosis of AMI is critical to reduce the mortality rate. As an important cardiac biomarker, creatine kinase (CK) has been used in the clinical diagnosis of AMI. However, it still remains a great challenge to realize highly sensitive and selective CK detection in blood specimens. Herein, we have developed an ultrasensitive platform for the detection of CK activity based on time-resolved (TR) luminescent lanthanide metal-organic framework nanoprobes (

Intracellular detection is highly desirable for biological research and clinical diagnosis, yet its quantitative analysis with noninvasivity, sensitivity, and accuracy remains challenging. Herein, a near‐infrared (NIR) dual‐excitation strategy is reported for ratiometric intracellular detection through the design of dye‐sensitized upconversion probes and employment of a purpose‐built NIR dual‐laser confocal microscope. NIR dye IR808, a recognizer of intracellular analyte hypochlorite, is introduced as energy donor and Yb,Er‐doped NaGdF4 upconversion nanoparticles are adopted as energy acceptor in the as‐designed nanoprobes. The efficient analyte‐dependent energy transfer and low background luminescence endow the nanoprobes with ultrahigh sensitivity. In addition, with the nonanalyte‐dependent upconversion luminescence (UCL) excited by 980 nm as a self‐calibrated signal, the interference from environmental fluctuation can be alleviated. Furthermore, the dual 808/980 nm excited ratiometric UCL is demonstrated for the quantification of the level of intracellular hypochlorite. Particularly, the intrinsic hypochlorite with only nanomolar concentration in live MCF‐7 cells in the absence of exogenous stimuli is determined. Such an NIR dual‐excitation ratiometric strategy based on dye‐sensitized UCL probes can be easily extended to detect various intracellular analytes through tailoring the reactive NIR dyes, which provides a promising tool for probing biochemical processes in live cells and diagnosing diseases., Near‐infrared (NIR) dye‐sensitized upconversion nanoprobes are designed for intracellular detection with high sensitivity and accuracy via a purpose‐built NIR dual‐laser confocal microscope system, providing a useful tool to study biological activities in live cells.

The effects of veneer orientation and loading direction on the mechanical properties of bamboo-bundle/poplar veneer laminated veneer lumber (BWLVL) were investigated by a statistical analysis method. Eight types of laminated structure were designed for the BWLVL aiming to explore the feasibility of manufacturing high-performance bamboo-based composites. A specific type of bamboo species named Cizhu bamboo (Neosinocalamus affinis) with a thickness of 6 mm and diameter of 65 mm was used. The wood veneers were from fast-growing poplar tree (Populus ussuriensis Kom.) in China. The bamboo bundles were obtained by a mechanical process. They were then formed into uniform veneers using a one-piece veneer technology. Bamboo bundle and poplar veneer were immersed in water-soluble phenol formaldehyde (PF) resin with low molecular weight for 7 min and dried to MC of 8–12 % under the ambient environment. All specimens were prepared through hand lay-up using compressing molding method. The density and mechanical properties including modulus of elasticity (MOE), modulus of rupture (MOR), and shearing strength (SS) of samples were characterized under loading parallel and perpendicular to the glue line. The results indicated that as the contribution of bamboo bundle increased in laminated structure, especially laminated on the surface layers, the MOE, MOR and SS increased. A lay-up BBPBPBB (B-bamboo, P-poplar) had the highest properties due to the cooperation of bamboo bundle and poplar veneer. A higher value of MOE and MOR was found for the perpendicular loading test than that for the parallel test, while a slightly higher SS was observed parallel to the glue line compared with perpendicular loading. Any lay-up within the homogeneous group can be used to replace others for obtaining the same mechanical properties in applications. These findings suggested that the laminated structure with high stiffness laid-up on the surface layers could improve the performance of natural fiber reinforced composites.

Two novel microporous metal–organic frameworks were obtained by combination of a tetratopic linker and linear trinuclear cobalt(II) and cadmium(II) cluster subunits. The complexes exhibit unprecedented topological features and unique magnetic and photoluminescence properties.

Rattle structure is a topic of great interest in design and application of nanomaterials due to the unique core@void@shell architecture and the integration of functions. Herein, we developed a novel “ship-in-a-bottle” method to fabricate upconverting (UC) luminescent nanorattles by incorporating lanthanide-doped fluorides into hollow mesoporous silica. The size of nanorattles and the filling amount of fluorides can be well controlled. In addition, the modification of silica shell (with phenylene and amine groups) and the variation of efficient UC fluorides (NaYF4:Yb,Er, NaLuF4:Yb,Er, NaGdF4:Yb,Er and LiYF4:Yb,Er) were readily achieved. The resulting nanorattles exhibited a high capacity and pH-dependent release of the anti-cancer drug doxorubicin (DOX). Furthermore, we employed these nanorattles in proof-of-concept UC-monitoring drug release by utilizing the energy transfer process from UC fluorides to DOX, thus revealing the great potential of the nanorattles as efficient cancer theranostic agent.

Two novel 3D porous metal–organic frameworks, {[Zn2(bpt)(btc)]·4H2O}n (1) and {[Cd2(bpt)(btc)(H2O)]·(DMA)2}n (2) (DMA = N,N-dimethylacetamide), were prepared based on 3,5-bis(pyrazinyl)-1,2,4-trizole (Hbpt) with the auxiliary ligand 1,3,5-benzenetricarboxylic acid (H3btc). Complex 1 could be described as a (3,6)-connected binodal 3D network with rutile topology and Schlafli symbol of (4.62)2(42.610.83), where its coordination framework exhibits a high thermal stability up to 420 °C as well as excellent boiling-water resistance. Complex 2 shows a (3,6,8)-connected trinodal 3D framework with a Schlafli symbol of (4.62)2(414.612.82)(44.610.8), which has not been reported previously. Interestingly, the gas-adsorption investigation discloses that complex 1 possesses a high enthalpy of H2 adsorption (9.6 kJ mol−1). Intensive solid-state fluorescence spectra of complexes 1 and 2 have also been determined.

An example of structural evolution from inclined polycatenation to parallel polyrotaxane-like interpenetration is demonstrated by modifying the (6,3) layer. Notably synergies of co-ligand binding mode and metal coordination geometry provide the appropriate constituent motifs necessary to instill this entanglement variation.

A polyhedral metal–organic framework (FJI-2) has been synthesized based on rare hexanuclear zinc clusters, which comprises 2.4 nm double-walled octahedral cages topologically featuring a new 3,12-connected structure. FJI-2 has a good H2 uptake capacity of 149.7 cm3 g−1 (1.34 wt %) at 77 K and 1.0 bar, and the IAST calculation predicts highly selective adsorption of CO2 over N2 and CH4.

Two three-dimensional coordination polymers were solvothermally prepared through in situ formation of a 2-sulfobenzoic acid ligand from a 2,2′-dithiobisbenzoic acid precursor involving the oxidative cleavage of its disulfide bond. Complex 1 shows neb-e topology, while complex 2 exhibits a scarcely reported twisting chiral dense 75.9 net.