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High entropy alloy nanoparticles encapsulated into nitrogen-doped carbon nanotubes show superior bifunctionality for the ORR and OER, evidenced by a battery performance of 214 mW cm−2, sustained for 200 h. [ABSTRACT FROM AUTHOR]

A Co–CoSe core–shell heterostructure encapsulated into nitrogen-doped carbon nanotubes enables superior zinc air battery performance (172 mW cm−2) and stability (970 h). The enhanced bifunctionality and stability originates from the modulated d band center and confinement effect, respectively. [ABSTRACT FROM AUTHOR]

Metal selenides have garnered significant attention as promising anode materials for sodium-ion batteries, thanks to their high theoretical capacity, excellent conductivity, and natural abundance. However, their potential is hampered by disappointing capacity retention and unsatisfactory lifespan, primarily attributed to volume expansion and unwanted structural collapse resulting from the insertion and extraction of relatively large Na+ ions during the charge and discharge processes. This feature article provides a brief overview of our endeavors to address the challenges associated with metal selenide-based anode materials, aiming to achieve high-performance electrode materials for sodium-ion batteries. Our strategy encompasses nanostructure design, materials composite engineering, heteroatoms doping, and topography and interface engineering. Additionally, future research directions are also outlined. [ABSTRACT FROM AUTHOR]

Poly(3,4-ethylenedioxythiophene) (PEDOT) aggregate-deposited counter electrodes (CEs) were applied to bifacial dye-sensitized solar cells with a cobalt complex electrolyte. The high transparency and excellent electrochemical activity of PEDOT CEs result in an impressive cell bifaciality of 0.92 under standard test conditions (AM 1.5G, 100 mW cm−2), and maximum power production of 11.3% under realistic conditions with an effective albedo of 50%. [ABSTRACT FROM AUTHOR]

Nickel-doped iridium echinus-like nanosheets (NiIr-ENS) have a superior acidic oxygen evolution reaction (OER) activity with a TOF of 1.72 s−1 at an overpotential of 300 mV, 8.6-fold higher than that of IrO2. [ABSTRACT FROM AUTHOR]

The great significance of geological research is to serve the development of society and economy. Laser-Induced Breakdown Spectroscopy (LIBS), a simple but efficient spectral analysis method, has advantages over traditional analysis methods. LIBS provides convenience for the exploration of geological resources. In this research, LIBS and Random Forest (RF) algorithm were combined for discriminating the provenance and lithology of rock samples from the Dajianggang area of Shuangyang and the Chaihe area of Daxing'anling. Four RF models were established to realize the discrimination of the provenance. The results showed that the model established by the preprocessing and variable selection of data has the best discrimination performance, and the accuracy reached 97.78%. The RF was also used to analyse the lithology of rock samples from the two areas. The classification accuracy of rock samples from the Dajianggang area was 100%, while that of rock samples from the Chaihe area was only 76.67% after optimization. The experimental results showed that the RF algorithm can effectively discriminate the provenance of rock and present more advantages in discriminating lithology of rocks with obvious characteristics in content. [ABSTRACT FROM AUTHOR]

Scattering interference (SI) is the possible scattering of intense radiation from the source, which is superimposed directly onto the resonance fluorescence signal of interest. It will lead to sham high results when using a non-dispersive optical system for As detection. To solve the SI of As, in this paper, a real-time suppression method named the non-fluorescent line ratios (NFLR) method was proposed after detailed analysis using dispersive atomic fluorescence spectrometry based on an ultraviolet digital micromirror device spectrometer (UV-DMD-AFS). Specifically, according to the characteristic of fast wavelength selection of UV-DMD-AFS, the source of SI and the effect of external factors on SI were analyzed, the non-fluorescent lines of As and the ratios of non-fluorescent lines to fluorescent lines (simplified as "Ratios") were determined, and the stability of the Ratios was studied under different parameters. The NFLR method suppressed the SI of As effectively, whose suppression proportion was 98.50–102.43%. Compared with the non-dispersive AFS, the NFLR method had a higher long-term accuracy (>99.20%) validated with certified reference materials (CRMs) of water quality samples. [ABSTRACT FROM AUTHOR]

Chemodynamic therapy (CDT) and photodynamic therapy (PDT) based on intratumoral generation of reactive oxygen species (ROS) have been playing crucial roles in conquering tumors. However, the above therapeutic methods are still constrained by the overexpressed tumor glutathione (GSH) and intrinsic tumor resistance to conventional organic photosensitizers. Herein, lanthanide-doped nanoparticles (LDNPs) were coated with inorganic bimetallic copper and manganese silicate nanospheres (CMSNs) and modified with sodium alginate (SA) for second near-infrared (NIR-II, 1000–1700 nm) imaging-guided CDT and PDT. Interestingly, cross-relaxation (CR) pathways between Ce3+ and Ho3+ and CR between Ce3+ and Er3+ are fully exploited to enable dual-mode upconversion (UC) and NIR-II downconversion (DC) emissions of LDNPs under 980 nm laser excitation. UC emission can induce CMSNs to produce toxic singlet oxygen (1O2) for PDT, and the released Mn2+ and Cu+ ions caused by GSH-induced degradation of CMSNs can react with endogenous H2O2 to produce hydroxyl radical (˙OH) for CDT. Significantly, the ultrabright NIR-II DC emission endows the systems with exceptional optical imaging capabilities. All results affirm the potency of such an "all in one" theranostic nanomedicine integrating PDT, CDT and remarkable NIR-II imaging abilities accompanied by the function of modulating tumor microenvironment in cancer theranostics. [ABSTRACT FROM AUTHOR]

Utilizing semiconductors to catalyze the conversion of N2 to NH3 has brought great promise in alleviating the issue of energy shortage. However, the wide band gap and high recombination rate of photogenerated (e−/h+) charge restrict their photocatalytic efficiency. Herein, a novel catalyst, N-Black In2O3−x/InVO4 was developed by coupling InVO4 nanosheets into defect-rich N-Black In2O3−x nanorods to construct multiple heterojunctions using the NH2-MIL-68(In) metal–organic-framework as a template. The N-Black In2O3−x/InVO4 multiple heterojunctions with oxygen vacancies could expand the light absorption range, act as electron trap centers, promote the separation of photogenerated carriers, and significantly improve the adsorption as well as activation of N2. Density functional theory (DFT) calculations revealed that the exposed (321) planes of the N-Black In2O3−x possess a higher surface energy than the (222) planes, which indicates that the exposed (321) planes can adsorb more N2 molecules and transform them into NH3 molecules. Consequently, owing to the efficient separation of photogenerated carriers, the nitrogen fixation rate of the N-Black In2O3−x/InVO4 heterostructure was as high as 2.07 mmol g−1 h−1 without any organic scavengers and precious-metal cocatalysts, which was 20.7, 2.4, 2.1, and 1.8 times that of NH2-MIL-68(In), N-In2O3, InVO4, and N-Black In2O3−x, respectively. [ABSTRACT FROM AUTHOR]

In recent years, Li3VO4 has been considered as a promising anode for advanced lithium-ion batteries due to its special crystal structure and high theoretical capacity. However, the poor electronic conductivity of the Li3VO4 material hinders its commercial applications. The mini-review highlights the microstructure, preparation, modification and possible insertion/deinsertion processes of Li3VO4. Finally, the future challenges and prospects related to its application are systematically discussed, including the controllable fabrication of Li3VO4 with the exposed certain crystal plane on a large scale, the enhancement of Li+ ion diffusion efficiency, in situ measurement technologies for exploring the real-time storage mechanism, and the green treatments for waste liquid. [ABSTRACT FROM AUTHOR]

Hollow cathode lamps (HCLs) are excitation light sources commonly used in hydride generation atomic fluorescence spectrometry (HG-AFS). There are obvious Pb interfering lines at 217.0 nm, 261.3 nm, and 283.3 nm in the atomic fluorescence spectrum excited by Se HCLs. This will induce erroneously measured results especially when using the non-dispersive detection method when Se and Pb are detected simultaneously. To solve the spectral interference caused by Se HCLs, in this paper, a UV digital micromirror spectrometer using a digital micromirror device (DMD) as a spatial light modulator, a grating as a spectroscope, and a photomultiplier tube (PMT) as a detector is designed for dispersive atomic fluorescence spectrometry. In addition, a modified DMD with a cover window made of Corning HPFS® 7980 standard grade fused silica was used to provides a higher transmittance of 180–320 nm. The most attractive features of this UV digital micromirror spectrometer are its simple structure, high sensitivity, no macroscopic moving parts, and rapid spectral analysis (0.419 s per spectrum). After optimizing DMD and PMT control parameters, the effects of the chemical generation system (K3Fe(CN)6, KBH4, and HCl) are investigated. The atomic fluorescence spectra of Se and Pb are obtained, and the detection limits of the analytical lines are discussed. The feasibility of the present method is confirmed by simultaneous detection of Se and Pb using water samples (GSBZ50031-94 and GSB07-1183-2000) and multi-element standard solution (GBW(E)080669) as reference materials. This study demonstrates the potential of the proposed spectrometer for dispersive HG-AFS, which appropriately reduces the purity requirements of the light source and the spectral interference from light sources. It is also applicable to simultaneous detection using multi-element HCLs or continuous light sources. [ABSTRACT FROM AUTHOR]

Herein, a novel strategy for the synthesis of various heterocyclic fused 2-aminoquinolines via palladium-catalyzed tandem cyclization of o-alkynylanilines with isocyanides has been developed. This process includes trans-oxy/aminopalladation, isocyanide insertion, elimination and 1,3-hydrogen migration. Besides high atom and step economy, this method shows good functional group compatibility with excellent chemo- and regioselectivities under mild reaction conditions. [ABSTRACT FROM AUTHOR]

A palladium-catalyzed oxidative allylation of bis[(pinacolato)boryl]methane to afford the corresponding homoallylic organoboronic esters with moderate to excellent yields is reported. This novel transformation provides an efficient strategy for the construction of homoallylic organoboronic esters in one step with a broad substrate scope. It is proposed that the palladium-catalyzed oxidative allylic C–H bond activation process may be involved in the catalytic cycle. [ABSTRACT FROM AUTHOR]

Triclinic (t-) Ba2V2O7 helical-like meso/nanosquares assembled from self-spiraling nanosheets have been controllably synthesized by a high-efficiency microwave irradiation-assisted surfactant process. The microstructure and morphology of the as-prepared t-Ba2V2O7 products were characterized by X-ray diffraction (XRD), field emission scanning electron microscopy (FE-SEM), transmission electron microscopy (TEM) and X-ray photoelectron spectroscopy (XPS). The results show that the spirals of stacked nanosheets grow along the z-axis of microsquares, leading to the formation of a helical shape. Based on parallel experiments and theoretical analysis of t-Ba2V2O7 helical mesosquares at different reaction stages, the formation mechanism has been proposed to be a “self-assembly–dissolution–recrystallization–Ostwald-ripening” mechanism. The helical structures with uniform morphology and size may find promising applications in a variety of fields. The SDBS-assisted microwave irradiation method offers an easy path to the controllable fabrication of helical Ba2V2O7meso/nanomaterials, which can be readily extended to the development of functional structures of other alkaline earth vanadates. Moreover, it is found that the helical-like materials exhibit unique magnetic properties, corresponding to shape evolutions with different particle sizes at continuous reaction time. [ABSTRACT FROM AUTHOR]

A mild tandem oxidative functionalization of allyl aromatic hydrocarbons was accomplished using the catalytic system of Pd(OAc)2/DMA under 1 atm O2. The green twofold C–O bond formation involving double allylic C–H oxygenation unlocks opportunities for markedly different synthetic strategies. Moreover, the reaction affords aryl α,β-unsaturated esters directly from readily available terminal olefins in moderate to good yields with excellent chemo- and stereoselectivities. [ABSTRACT FROM AUTHOR]

The faradaic efficiency of Bi2WO6 is 62.0% at −0.3 V vs. RHE, an improvement of 1.4- and 1.8-times relative to Bi2O3 and WO3 for the nitrate reduction reaction. In addition, the catalysis occurring on Bi2WO6 follows the pathway: *NO3–*NO2–*NO–*NOH–*HNOH–*H2NOH–*NH3, as verified by operando Raman spectroscopy and theoretical calculations. [ABSTRACT FROM AUTHOR]

Correction for ‘A UV digital micromirror spectrometer for dispersive AFS: spectral interference in simultaneous determination of Se and Pb’ by Chen Tao et al., J. Anal. At. Spectrom., 2018, 33, 2098–2106. [ABSTRACT FROM AUTHOR]

Highly-photoluminescent ZnSe quantum dots with 72% quantum yield and 22 nm full width at half maximum were synthesized with more reactive precursors viaa non-injection approach with high synthetic reproducibility; 31P NMR provided insight into the formation mechanisms of ZnSe monomers. [ABSTRACT FROM AUTHOR]

In this work, we develop an in situ biomass-confined approach to fabricate an atomically dispersed Fe/NC catalyst for ORR. The acquired Fe/NC demonstrates glorious oxygen reduction reaction (ORR) activity ( E 1/2 : 0.858 V) in alkaline media and long-term cycling stability (∼750 h) in a homemade liquid zinc-air battery.

The faradaic efficiency of Bi 2 WO 6 is 62.0% at -0.3 V vs. RHE, an improvement of 1.4- and 1.8-times relative to Bi 2 O 3 and WO 3 for the nitrate reduction reaction. In addition, the catalysis occurring on Bi 2 WO 6 follows the pathway: *NO 3 -*NO 2 -*NO-*NOH-*HNOH-*H 2 NOH-*NH 3 , as verified by operando Raman spectroscopy and theoretical calculations.

CoO/Fe 3 O 4 nanosheets exhibit a superior rechargeable zinc-air battery (ZAB) performance of 276 mW cm -2 and stability over 600 h. The all-solid-state ZAB also affords a high power density of 107 mW cm -2 .

Unprecedented regioselective trans -hydroboration and carboboration of unbiased electronically internal alkynes were realized via a nickel catalysis system with the aid of the directing group strategy. Furthermore, the excellent α- and β-regioselectivity could be accurately switched by the nitrogen ligand (terpy) and phosphine ligand (Xantphos). Mechanistic studies provided an insight into the rational reaction process, that underwent the cis -to- trans isomerization of alkenyl nickel species. This transformation not only expands the scope of transition-metal-catalyzed boration of internal alkynes but also, more particularly, portrays the vast prospects of the directing group strategy in the selective functionalization of unactivated alkynes., Competing Interests: There are no conflicts to declare., (This journal is © The Royal Society of Chemistry.)

Chemodynamic therapy (CDT) and photodynamic therapy (PDT) based on intratumoral generation of reactive oxygen species (ROS) have been playing crucial roles in conquering tumors. However, the above therapeutic methods are still constrained by the overexpressed tumor glutathione (GSH) and intrinsic tumor resistance to conventional organic photosensitizers. Herein, lanthanide-doped nanoparticles (LDNPs) were coated with inorganic bimetallic copper and manganese silicate nanospheres (CMSNs) and modified with sodium alginate (SA) for second near-infrared (NIR-II, 1000-1700 nm) imaging-guided CDT and PDT. Interestingly, cross-relaxation (CR) pathways between Ce 3+ and Ho 3+ and CR between Ce 3+ and Er 3+ are fully exploited to enable dual-mode upconversion (UC) and NIR-II downconversion (DC) emissions of LDNPs under 980 nm laser excitation. UC emission can induce CMSNs to produce toxic singlet oxygen ( 1 O 2 ) for PDT, and the released Mn 2+ and Cu + ions caused by GSH-induced degradation of CMSNs can react with endogenous H 2 O 2 to produce hydroxyl radical (˙OH) for CDT. Significantly, the ultrabright NIR-II DC emission endows the systems with exceptional optical imaging capabilities. All results affirm the potency of such an "all in one" theranostic nanomedicine integrating PDT, CDT and remarkable NIR-II imaging abilities accompanied by the function of modulating tumor microenvironment in cancer theranostics.

A palladium-catalyzed oxidative allylation of bis[(pinacolato)boryl]methane to afford the corresponding homoallylic organoboronic esters with moderate to excellent yields is reported. This novel transformation provides an efficient strategy for the construction of homoallylic organoboronic esters in one step with a broad substrate scope. It is proposed that the palladium-catalyzed oxidative allylic C-H bond activation process may be involved in the catalytic cycle.

Highly-photoluminescent ZnSe quantum dots with 72% quantum yield and 22 nm full width at half maximum were synthesized with more reactive precursors via a non-injection approach with high synthetic reproducibility; (31)P NMR provided insight into the formation mechanisms of ZnSe monomers., (This journal is © The Royal Society of Chemistry 2011)

Total filterable mercury (TFM) and lead-210 ((210)Pb) were measured for a one-year air particulate sample series collected weekly at Resolute (74.7 degrees N, 95.0 degrees W), a Canadian high Arctic site, during July 1999 and June 2000. The measurements showed a clear time lag of two months between the peak concentrations of TFM and (210)Pb.