The use of Bismuth (Bi) as an anode material for aqueous rechargeable alkaline batteries (ARABs) has gained significant attention due to its redox reaction and suitable operating potential. However, the conductivity, rate capability, and cycling stability of the anode need to be further improved. In this work, a novel porous and conductive nitrogen-doped carbon skeleton (NCS) is prepared by in situ polymerization of polyaniline on carbon cloth followed by carbonization, providing a robust and binder-free support. This strategy enhances surface area, conductivity, and porosity, promoting efficient charge transport and abundant active sites. The growth of BiOBr nanoarrays on NCS is obtained using a simple chemical vapor deposition (CVD) technique. Benefiting from the porous and conductive NCS, along with the topo-tactic transformation of BiOBr, favorable reaction kinetics and effective usage of active material are obtained. The well-designed binder-less Bi anode exhibits a prominent specific capacity (383 mAh g-1 at 3 A g-1, 267 mAh g-1 at 20 A g-1), and achieves outstanding stability with capacity retention of 85.9% after 2000 cycles. In addition, the assembled Co(OH)2//Bi full battery exhibits 70.4 Wh kg-1 energy density. Furthermore, this study promotes the development of binder-less aqueous Bi anodes for ARABs and demonstrates their significant potential in practical applications because the entire procedure is simple and scalable.

Two-dimensional (2D) BiOBr has garnered significant interest due to its exceptional optoelectronic properties. Currently, reported 2D BiOBr primarily exhibits n-type conductivity. However, in the field of optoelectronics, particularly within complementary metal oxide semiconductor (CMOS) integrated circuits, there is an urgent demand for high-quality p-type 2D semiconductors. In this study, we present the synthesis of high-quality, large-scale p-type 2D BiOBr crystals using chemical potential modulation chemical vapor deposition (CPMCVD). Notably, the conduction polarity of 2D BiOBr can be precisely controlled by modulating the oxygen chemical potential during the synthesis process. Density functional theory (DFT) calculations indicate that high oxygen chemical potential promotes the formation of bismuth vacancies in 2D BiOBr, resulting in p-type conductivity. Conversely, as the oxygen chemical potential decreases, oxygen vacancies become the predominant defects, leading to n-type BiOBr. Furthermore, both p-type and n-type high-performance field-effect transistors (FETs) based on 2D BiOBr have been fabricated. The p-type FETs exhibit a superior hole mobility of 26.28 cm(2) V-1 s(-1) and on/off ratio exceeding 10(4). The n-type FETs demonstrate an electron mobility of 59.59 cm(2) V-1 s(-1), surpassing those reported for most n-type FETs. This breakthrough in the precise control of conduction polarity in 2D BiOBr using CPMCVD not only represents a significant milestone but also greatly expands its potential applications in advancing CMOS technology.

Although some progress has been made in the synthesis of p-type two-dimensional (2D) WS2, the hole mobility of WS2 field-effect transistors (FETs) is still very low, significantly impeding its application in logic complementary circuits. In this study, p-type 2D WS2 has been successfully prepared by liquid-phase assisted space-confined chemical vapor deposition (LASCVD) method and machine learning (ML) has been employed to optimize the process parameters of the growth of WS2 nanosheets. Results show that, under the optimal growth conditions, the maximum domain size of WS2 monolayer reaches 475 mu m. Additionally, W vacancies in WS2 nanosheets have been observed through STEM-HAADF, Raman and PL analysis, contributing to the p-type characteristic of 2D WS2. Moreover, p-type high-performance FETs based on the WS2 monolayer have been fabricated, exhibiting a high hole mobility of 46.87 cm2 V-1 s-1 and an on/off ratio of 105. This study provides a promising direct synthesis method for p-type 2D TMDCs.

Hybrid quasi-two-dimensional (quasi-2D) perovskites have attracted great interest due to their excellent photovoltaic and light-emitting properties, which enable the rapid development of high-performance perovskite-based solar cells, light-emitting diodes, and lasers. Although many efforts have been made to improve the quality and stability of organic-inorganic perovskites, the controlled synthesis of high-quality layered perovskites remains challenging. Here, single-crystalline quasi-2D (HA)2(MA)n-1PbnI3n+1 perovskites with layer numbers of n from 1 to 3 have been synthesized in a controllable manner, exhibiting stable lattice structures and tunable optical emission. Structurally, hexylamine (HA) with longer alkyl chains was used as an organic spacer in Ruddlesden-Popper (RP) phase perovskites to improve the chemical stability of perovskites. Various ratios of precursor materials were adopted for separating pure and large-scale quasi-2D (HA)2(MA)n-1PbnI3n+1 perovskites, in which different layer-number perovskites with tunable band gaps were obtained with the modulated fluorescence lifetimes. Our lattice structural and fluorescence-lifetime characterizations of RP-phase perovskites provide critical information on the emerging quasi-2D perovskite-crystal systems and their fluorescence relaxation dynamics. The employed strategy to synthesize high-quality perovskites (HA)2(MA)n-1PbnI3n+1 is technically essential to develop the rising perovskite-based photovoltaic and light-emitting applications.

The performance of BiOBr in photocatalytic nitrogen (N2) fixation is suboptimal, attributed to the weak chemisorption and activation of N2 by surface atoms. In our study, we achieved the formation of two-dimensional (2D) bismuth (Bi) on BiOBr nanosheets through in situ annealing in hydrogen atmosphere and successfully constructed a unique 2D-2D Bi/BiOBr ohmic heterojunction using a one-step method. Notably, the Bi/BiOBr heterojunction was utilized for photocatalytic N2 fixation under visible light (λ > 400 nm) in ultrapure water, demonstrating an exceptional N2 fixation rate of 376.16 μmol g-1 h-1. This rate is 7.7 and 4.1 times higher than those of BiOBr and BiOBr-OVs, respectively. The improved photocatalytic efficiency is attributed to the significantly enhanced N2 adsorption capability and more effective separation of photogenerated carriers, both stemming from the distinctive 2D/2D architecture of the Bi/BiOBr heterojunction. This work demonstrates that 2D Bi offers active sites that facilitate photocatalytic N2 fixation and introduces an approach to the design and construction of 2D/2D photocatalysts for applications spanning catalysis, optoelectronics, electronics, and beyond.

Distal biaxial atropisomers are typical structures in chiral catalysts and ligands and offer a wide variety of applications in biology and materials technology, but the development of efficient synthesis of these valuable scaffolds is still in great demand. Herein, we describe a highly efficient iridium catalyzed asymmetric C-H alkylation reaction that provides a range of new distal biaxial atropisomers with excellent yields (up to 99%) and stereoselectivity (up to 99% ee and essentially one isomer). Based on this unprecedented strategy, a polycyclic skeleton with five successive chiral centers as well as C-C and C-N (or N-N) two distal chiral axes was created successfully in mild circumstances. In addition, the optically pure products bearing fluorophores show circular polarized luminescence (CPL) properties, being potential candidate materials for CPL applications.

Twisted stacking-induced moir & eacute; superlattice of two-dimensional (2D) materials have aroused surging interest due to their novel properties and promising applications in quantum technologies. However, problems such as unavoidable interfacial contamination in the prevailing mechanically transferred method, and limited members of 2D materials for constructing twisted homostructures/heterostruc tures impede the advance of 2D moir & eacute; superlattice. Here, bottom-up growth of high-quality bismuth oxychloride twisted homostructures (BiOCl THS) is achieved by a precursor-regulated chemical vapor deposition (CVD) method. In contrast to the conventional screw-dislocation-driven growth of spiral- like nanosheets, the as-prepared BiOCl THSs show a wide range of twist angles and large lateral sizes. A unique secondary twisted nucleation growth mechanism is revealed by multiple characterizations and theoretical calculations. It is demonstrated that the adsorption of polar H2O molecule on BiOCl can lead to a stable nucleation with rotation angles. Furthermore, benefitting from the bottom-up growth of the twisted homostructures, clear moir & eacute; patterns and moir & eacute; potential induced variation of interlayer coupling and exciton resonances were observed in the BiOCl THS. Our work provides a promising strategy for controllable preparation of high-quality 2D moir & eacute; superlattice.

BiOI is a promising photocatalytic nitrogen fixing material, with a significant photoresponse in the visible light spectrum. Future development of BiOI catalysts will depend on extending the lifespan of photogenerated carriers, modifying the proper valence band location, and enhancing sample stability. Here, a BiOI-FTO photocatalytic nitrogen fixation device is initially built after the BiOI nanosheets array is vertically grown on the surface of FTO conductive glass by CVD. Schottky junction is formed owing to the compact growth of BiOI on FTO and the difference in work functions between them. Consequently, photogenerated holes and electrons of BiOI are separated under the simulated visible light irradiation. Photogenerated electrons of BiOI are moved to the surface of FTO to take part in the nitrogen fixation reaction. Compared with BiOI nanosheets, the light absorption range in visible light is expanded and the carrier separation efficiency of BiOI-FTO is boosted. The photocatalytic nitrogen fixation performance of BiOI-FTO reaches 103.2 mu mol g-1 h-1, which is about 9 times greater than that of pure BiOI nanosheets, and it still displays good stability after 100 h of catalysis. This work provides a fresh strategy for creating efficient and stable photocatalytic nitrogen fixation devices based on BiOI.

Allium crop breeding remains severely hindered due to the lack of high-quality reference genomes. Here we report high-quality chromosome-level genome assemblies for three key Allium crops (Welsh onion, garlic and onion), which are 11.17 Gb, 15.52 Gb and 15.78 Gb in size with the highest recorded contig N50 of 507.27 Mb, 109.82 Mb and 81.66 Mb, respectively. Beyond revealing the genome evolutionary process of Allium species, our pathogen infection experiments and comparative metabolomic and genomic analyses showed that genes encoding enzymes involved in the metabolic pathway of Allium -specific flavor compounds may have evolved from an ancient uncharacterized plant defense system widely existing in many plant lineages but extensively boosted in alliums. Using in situ hybridization and spatial RNA sequencing, we obtained an overview of cell-type categorization and gene expression changes associated with spongy mesophyll cell expansion during onion bulb formation, thus indicating the functional roles of bulb formation genes.

An asymmetric isomerization/intramolecular coupling reaction of allylic alcohols to synthesize chiral dihydrocoumarins was successfully accomplished through ruthenium catalysis. This method demonstrates a wide substrate applicability, excellent tolerance for various functional groups, and good enantioselectivities (up to 90% ee). It provides a convenient pathway to produce a diverse range of structurally distinct chiral dihydrocoumarins in good efficiency.

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A highly efficient method achieves precise construction of alkyl chiral centers at remote C3-positions in five-membered S/O-heterocycles via cobalt-catalyzed asymmetric remote hydroalkylation of heterocyclic alkenes.

Contriving an industry-compatible method for fabricating purely high-quality p-type two-dimensional (2D) field effect transistors (FETs) has been proved to be pressing but challenging due to the strong interfacial coupling and thus tight Fermi level pinning (FLP). Herein, by employing density functional theory calculations, a straightforward but effective strategy is proposed to achieve high-quality p-type contact in few-layer TeO2-Pt junction by using a build-in intercalation to suppress the FLP and shield the damage from electrodes to the excellent electrical properties of TeO2 such as its ultra-high hole mobility. Specifically, the increase of TeO2 layer number will make the charge distribution of VBM and CBM be more lumped in the inner core layer, as a result, the outlying Te-O sublayer can act as an inserting layer like BN to protect the semiconducting electronic states and avoid gapstate pinning. Thus, as the TeO2 layer increases from 1 L to 3 L, (I) strong FLP in metal-TeO2 interfaces is gradually unpinned; (II) the polarity of Pt-TeO2 contact reverses from n-type to p-type; (III) the excellent electrical properties of TeO2 such as hole effective mass is preserved as original despite strong charge transfer occurring at the interface. Besides, the tunnelling barrier at the interface is close to zero. This is quite different from introducing an extern BN intercalation, in which case the tunnelling through BN will prominently reduce the overall hole current. In addition, the contacts between 2D metal electrodes and monolayer TeO2 are found to obey the Schottky-Mott rule, and thereby p-type Ohmic contacts can be obtained at TeO2-VS2, -NbS2 interfaces. Whereas, a relatively large tunnelling barrier exists at the 2D metal-TeO2 interfaces. Our findings are quite essential and beneficial for designing high-performance p-type 2D FETs.

The effect of the counter-anion in the azolium pre-catalyst on enantio-control in oxidative NHC catalysis is demonstrated systematically for the first time in acylative kinetic resolution of oxindole-derived tertiary alcohols.

A metal-controlled divergent protocol for the synthesis of α- and β-substituted γ-butyrolactones was developed through intramolecular coupling of epoxides with alcohols. This method provides an efficient and practicable way to afford γ-butyrolactones with good efficiency, excellent regioselectivity, and broad substrate scope.

Herein, we report unprecedented Ni-catalyzed chemodivergent annulations to produce the 3,4-dihydrocoumarins and 2H-chromenes that are important attractive building blocks in many biologically active compounds. By the introduction of dcype ligand, a range of 3,4-dihydrocoumarins can be afforded with good to excellent yield and wide functional group tolerance via chemoselective intramolecular tandem isomerization/esterification. In the absence of ligand, a useful synthesis of 2H-chromenes has been developed through a nickel-catalyzed direct O-allylic substitution with good to excellent efficiency.

Aryl ketones are one of the most important classes of organic compounds, and widely present in various pharmacological compounds, biologically active molecules and functional materials. Presented herein is a facile synthetic method for the construction of ketones via Ni-catalyzed cross coupling of epoxides with aryltriflates. A range of easily accessible epoxides can be highly regioselectively converted to the corresponding aryl ketones with good yields in a redox neutral fashion.

Strong Fermi-level pinning (FLP) always occurs at the two-dimensional (2D) semiconductor-metal interface due to the complex interfacial charge transfer. By using monolayer (ML) Bi2OS2, an emerging 2D semiconductor with the highest electron mobility, the Schottky barrier heights (SBHs) and origin of charge transfer at Bi2OS2-metal interfaces are systematically studied based on density functional theory calculations. In 3D metal-Bi2OS2 interfaces, the formation of chemical bonding and the effect of Pauli exchange repulsion are found to be responsible for the strong interfacial charge transfer, resulting in strong FLP, and the direction of charge transfer induced by the two factors is opposite. Besides, an extra interfacial charge transfer is expected to equilibrate the Fermi level when the work functions (WFs) of metal electrodes are out of the range of electron affinity energy and ionization energy of semiconductors. For 2D metal-ML Bi2OS2 interfaces, surprisingly, the FLP is found to be entirely suppressed, and thereby, the 2D metal-Bi2OS2 contacts obey the conventional Schottky-Mott model. Such intriguing behavior arises from the 2D metal electrodes chosen in this work can effectively shield the effect of Pauli exchange repulsion. Consequently, wide-range and linear-tunable SBHs can be obtained and the conversion from n-type Ohmic contact to p-type Ohmic contact can be achieved by using 2D metal electrodes with different WFs. This study not only provides a theoretical foundation for selecting favorable metal electrodes in devices based on ML Bi2OS2, but also helps to enhance the understanding of the mechanism of interface interaction between metals and 2D semiconductors.

Bioorthogonal chemistry, referring to the rapid and selective synthesis of imaging and/or therapeutic molecules in live animals via transition metal-mediated non-natural chemical transformation without disrupting endogenous reactions, has greatly expanded the tools and techniques for biomedicine. However, owing to safety concerns associated with metal toxicity, selectivity, sensitivity and stability, efficient bioorthogonal reactions that can be reliably executed in complex biological environments remain challenging. In this study, an intelligent, versatile bioorthogonal catalyst based on ultrasmall poly(acrylic acid)-modified copper nanocomplexes (Cu@PAA NCs) to achieve high spatiotemporal catalytic efficacy is established. The catalytic activity of the Cu@PAA NCs can be reversibly regulated via valence state interconversion between Cu(II) and Cu(I) under exogenous ultrasound irradiation, promoting off-target prodrug activation in lesion sites through the Cu(I)-catalyzed azide-alkyne cycloaddition reaction. Moreover, ultrasound-triggered electron-hole separation endows the Cu@PAA NCs with robust sonosensitizing ability for sonodynamic therapy. Furthermore, the Cu@PAA NCs exhibit enhanced contrast in magnetic resonance and photoacoustic imaging. Notably, the renal-clearable Cu@PAA NCs exhibit intrinsically benign biocompatibility. This spatiotemporally ultrasound-mediated bioorthogonal catalysis not only expands the repertoire of in situ therapeutic agents but also provides a new avenue for disease theranostics.