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The performances of heterogeneous catalysts can be effectively improved by optimizing the catalysts via appropriate structure design. Herein, we show that the catalysis of cuprous sulfide can be boosted by constructing the hybrid structure with Cu2S nanoparticles on amorphous CuSx matrix (Cu2S/CuSx). In the photocatalytic CO2 reduction under visible light irradiation, the Cu2S/CuSx exhibited a CO production rate at 4.0 µmol h−1 that is 12-fold higher than that of the general Cu2S catalyst. Further characterizations reveal that the Cu2S/CuSx has two reaction systems that realize the biomimetic catalysis, involving in the light reaction on the Cu2S nanoparticle–CuSx matrix heterojunctions for proton/electron production, and the dark reaction on the defect-rich CuSx for CO2 reduction. The CuSx matrix could efficiently activate CO2 and stabilize the split hydrogen species to hinder undesired hydrogen evolution reaction, which benefits the proton–electron transfer to reduce CO2, a key step for bridging the two reaction systems.

The most essential characteristic of any fluid is the velocity field, and this is particularly true for macroscopic quantum fluids1. Although rapid advances2–7 have occurred in quantum fluid velocity field imaging8, the velocity field of a charged superfluid—a superconductor—has never been visualized. Here we use superconducting-tip scanning tunnelling microscopy9–11 to image the electron-pair density and velocity fields of the flowing electron-pair fluid in superconducting NbSe2. Imaging of the velocity fields surrounding a quantized vortex12,13 finds electronic fluid flow with speeds reaching 10,000 km h–1. Together with independent imaging of the electron-pair density via Josephson tunnelling, we visualize the supercurrent density, which peaks above 3 × 107 A cm–2. The spatial patterns in electronic fluid flow and magneto-hydrodynamics reveal hexagonal structures coaligned to the crystal lattice and quasiparticle bound states14, as long anticipated15–18. These techniques pave the way for electronic fluid flow visualization studies of other charged quantum fluids. Atomic-scale visualization of the superfluid velocity field, the electron-pair density and the superfluid current density in an electron-pair superfluid surrounding an Abrikosov vortex in a superconducting sample of NbSe2 is demonstrated, using superconducting-tip scanning tunnelling microscopy.

It has long been a challenge to fabricate angstrom-sized functional pores for mimicking the function of biological channels to afford selective transmembrane transport. In this study, we describe a facile strategy to incorporate ionic elements into angstrom-sized channels using de novo encapsulation of charged dye molecules during the interface polymerization of a three-dimensional covalent organic framework (3D COF). We demonstrate that this approach is tailorable as it enables control over both the type and content of the guest and thus allows manipulation of the membrane function. The resulting membranes exhibit excellent permselectivity and low membrane resistance, thereby indicating the potential for harvesting salinity gradient (blue) energy. As a proof-of-concept study, the reverse electrodialysis device coupled with positive and negative dye encapsulated COF membranes afforded a power density of up to 51.4 W m-2 by mixing the simulated seawater and river water, which far exceeds the commercialization benchmark (5 W m-2). We envision that this strategy will pave the way for constructing new multifunctional biomimetic systems.

In this work, we show for the first time that high-silica zeolites (MFI, TON, MTT, and *MRE) could be synthesized from a combined strategy of both zeolite seeding and alcohol filling in the absence of organic structure-directing agents (OSDAs). High-silica ZSM-5 zeolites with Si/Al ratios ranging from 38 to 240 (TF-Al-ZSM-5) could be synthesized via this route. The key to the success of this technique was the employment of an aluminosilicate precursor with a fully 4-coordinated aluminum species as the initial source, wherein the rearrangement and condensation of the silicate species, rather than the aluminate species, occurred during zeolite crystallization. In addition, heteroatoms, such as Fe and B, could be incorporated into the zeolite frameworks. Catalytic tests for the methanol-to-propylene (MTP) reaction exhibited good catalytic performance for TF-Al-ZSM-5, which was comparable to that of the aluminosilicate ZSM-5 zeolite synthesized with OSDAs. Hence, this method offers viable opportunities for the industrial production and catalytic application of high-silica zeolites in the future.

Carbon monoxide (CO) catalytic oxidation has gained increasing interest in recent years due to its application prospects. The noble metal catalysts commonly exhibit outstanding CO catalytic oxidation activity. Therefore, this article reviewed the recent research on the application of noble metal catalysts in the catalytic oxidation of CO. The effects of catalyst support, dopant, and physicochemical properties on the catalytic activity for CO oxidation are summarized. The influence of the presence of water vapor and sulfur dioxide in the reaction atmosphere on the catalytic activity in CO oxidation is emphatically discussed. Moreover, this paper discussed several reaction mechanisms of CO catalytic oxidation on noble metal catalysts. Finally, the challenges of removing CO by catalytic oxidation in practical industrial flue gas are proposed.

The application of RNA interference (RNAi) methods to control lepidopteran pests is difficult because of lower RNAi efficiency in these insects. Numerous studies concluded that dsRNA degrading nucleases (dsRNases) could be one of the factors involved in reducing RNAi efficiency in insects. The knockdown of genes coding for dsRNases is not successful due to inefficient RNAi in these insects. CRISPR/Cas9 system could help to knockout genes coding for dsRNases. Here, we knocked out two gut-specific dsRNase genes identified in the previous studies by using CRISPR/Cas9 system. The homozygous mutant strains containing knockout of one of the two dsRNases (SL1KO or SL2KO) and the double genes homozygous strain with knockout of both dsRNases (SL1SL2KO) showed 79.3%, 40.4% and 96.3% decrease in dsRNA-degrading activity, respectively. The nuclease activity in the gut fluid and the hemolymph was decreased by 83.2% and 23.3%, respectively, in SL1SL2KO strain as compared to the WT. Also, the level of fed dsRNA was almost 20 times higher in the SL1SL2KO strain than that in WT strain, but a similar dsRNA persistence time as detected in the hemolymph collected from SL1SL2KO and WT. Comparative analysis of RNAi response between SL1SL2KO and the WT strain showed that knockout of both dsRNases increased RNAi efficiency as the target gene mRNA levels were suppressed by feeding dsRNA to SL1SL2KO.

As a result of high-density urbanization and climate change, both the frequency and intensity of extreme urban rainfall are increasing. Drainage systems are not designed to cope with this increase, and as a result, floods are becoming more common in cities, particularly in the rapidly growing cities of China. To better cope with more frequent and severe urban flooding and to improve the water quality of stormwater runoff, the Chinese government launched the national Sponge City Construction (SCC) program in 2014. The current SCC design standards and guidelines are based on static values (e.g., return periods, rainfall intensities, and volume capture ratio (VCR)). They do not fully acknowledge the large differences in climate conditions across the country and assume that the hydraulic conditions will not change over time. This stationary approach stems from the traditional engineering approach designed for grey infrastructure (following a “one size fits all” approach). The purpose of this study was to develop a methodology to assess the VCR baseline (before construction in the pre-development stage) and changes in VCR (difference between the VCR of the pre- and post-development stage). The VCR of the post-development stage is one of the required indicators of the Assessment Standard for Sponge Cities Effects to evaluate SCC projects. In this study, the VCR was derived from remote-sensing-based land use land cover (LULC) change analysis, applying an unsupervised classification algorithm on different Landsat images from 1985 to 2015. A visualization method (based upon Sankey chart, which depicts the flows and their proportions of components) and a novel and practical partitioning method for built-up regions were developed to visualize and quantify the states and change flows of LULC. On the basis of these findings, we proposed a new indicator, referred to as VCRa-L, in order to assess the changes in urban hydrology after SCC construction. This study employed the city of Nanjing as a case study and analyzed detailed information on how LULC changes over time of built-up areas. The surface area of the urban and built-up areas of Nanjing quadrupled from 11% in 1985 to 44% in 2015. In the same period, neither the entire city nor its subregions reached the VCR target of 80%. The proposed new methodology aims to support national, regional, and city governments to identify and prioritize where to invest and implement SCC measures more effectively in cities across China.

Hypoxia is one of the most important features of various diseases including solid tumors. It is of significant clinical importance for hypoxia analysis in tumors, and the analysis of hypoxia can be moved away to the indirect detection of nitroreductase. Various fluorescence methods have been developed for the analysis of nitroreductase and tumor hypoxia due to their simplicity, non-invasiveness and excellent spatial-temporal resolution. Here, we synthesized a multifunctional fluorophore, which possesses larger π-conjugation structure, leading to the red-shift of absorption and fluorescence emission to long-wavelength region. This fluorophore (RCOH) can be further used to prepare the off-on hypoxia probe (RCO-NTR) by introducing the electron withdrawing group of nitrobenzyl, leading to the quenching of fluorescence emission through an electron transfer process. After reaction with NTR accompanied by NADH as an electron donor, the nitro group in the RCO-NTR probe can be reduced and then the RCOH fluorophore can be released through rearrangement and elimination, leading to the enhancement of fluorescence signal. Thus, the prepared RCO-NTR probe can be used for nitroreductase analysis, which can be further used for hypoxia imaging at both cellular and animal levels.

Due to the inference of the uneven shallow water seabed and the surrounding islands, the wind-generated waves around or in a reef lagoon are rather complicated, and critical to the safety of floating structures deployed near islands or inside a lagoon. This paper aims to find a feasible analysis tool for the wave simulations near islands and reefs. The proposed three methods of grid techniques of WAVEWATCH III (WW3) are assessed by using on-site measured data which was collected and accumulated for about 5 years since August 2014 by a wave observation system deployed inside and outside a reef lagoon in South China Sea. In the assessments, the wave statistics including the correlation coefficients, root mean square errors, and their variances are used to quantify the precisions of the simulation results of the significant wave heights, mean wave periods, and peak wave directions at two sites. Among the three methods, the Multi-scale Zone and Multi-scale grid Technique (MZMGT) established on unstructured triangular grids exhibits better results in terms of the accuracy and CPU cost. In addition, the bimodal feature of wave spectra was observed at both sites of the reef lagoon in different typhoon events. The wave characteristics inside the reef lagoon and open sea are also analyzed.

This work demonstrated a pressure-based biosensor integrated with a flexible pressure sensor and an electrochromic device for visual detection. Initially, a sandwich-type immunoreaction for target carcinoembryonic antigen (CEA, as a model analyte) was carried out using the capture antibody (cAb) and platinum nanoparticles-labeled detection antibody (PtNPs-dAb) in a reaction cell. The added hydrogen peroxide (H2O2) could be catalyzed by the PtNPs to generate oxygen (O2). In a sealed chamber, the pressure increased with the overflowing O2. Meanwhile, a skin-inspired flexible pressure sensor with excellent sensing performance was fabricated to monitor the pressure change in real time. Thus, the electrical signal of the pressure sensor could reveal the target concentration. Moreover, a voltage-regulated electrochromic device based on polyaniline (PANI) and tungsten oxide (WO3) was integrated into the platform to provide a visualized readout. According to the electrical signal of the pressure sensor, the electrochromic device would change its color from green to blue, which also revealed the target concentration and could be observed by the naked eye. Under optimal conditions, the biosensor presented a high sensitivity for CEA in a detectable range of 0.2-50 ng/mL. The limit of detection (LOD) was 94 pg/mL. The selectivity, reproducibility, and accuracy were also satisfying. Furthermore, this immunoassay gives a path for developing visualized biosensors in point-of-care settings.

All-inorganic cesium lead iodine perovskite materials (CsPbI3) have been widely studied and applied to PSCs because of their excellent thermo-chemical stability and suitable bandgap. However, CsPbI3 still faces the issue of phase transitions under humid conditions. In this study, cesium trimethylacetate (CsTa) organic cesium salt is employed as an additive in the CsPbI2.84Br0.16 film. The results show that CsTa can have multifunctional effects on CsPbI2.84Br0.16 perovskite stability. The steric hindrance blocking effect of Ta− anions can efficiently prevent the tilt of the [PbI6]4− octahedrons to inhibit the phase transition process from the corner-shared perovskite to the edge-shared non-perovskite structure. The Ta− groups are firmly located at the X site of the perovskite structure, leading to an increase in the energy barrier for X-site vacancy generation (from 0.816 eV to 1.217 eV), which slows the phase transition process induced by lattice disorder. Meanwhile, the decrease in crystal grain size after adding CsTa is beneficial for perovskite phase stability due to the decreased surface Gibbs free energy of CsPbI2.84Br0.16 crystals. In addition, the reduced defect density brought about by the improved crystal quality is also favorable for increasing the energy barrier for the phase transition from the perovskite phase to the δ phase. Finally, a champion PCE of 16.59% can be achieved from the HPbI3-prepared PSCs with adding CsTa, which maintain 80.88% of the initial performance after more than 1200 hours in air (RH: ∼20%). Meanwhile, both 0.1-CsTa and 0.2-CsTa PbI2-prepared PSCs deliver excellent stability and maintain above 80% of the initial PCE after nearly 2000 hours. Impressively, under a relatively high thermal/moisture (temperature: 80 °C/RH: ∼80%) environment, the 0.2-CsTa devices can still retain 87.41% of the initial performance after 500 hours of storage.

Understanding of crystallization mechanisms of molecular sieves is driven by the broad range of usefulness and unique properties they possess. It is still difficult to obtain information related to the crystallization mechanism of molecular sieves, partly because the materials are generally prepared under hydrothermal conditions and the whole reaction happens in the "black box" autoclave. In this work, 2D 1 H DQ-SQ NMR results clearly demonstrate that it is not only the electrostatic interactions between organic structure-directing agents (OSDAs) and the framework, but also the correlation among OSDAs playing the dominant structural directing roles during the crystallization process. Our fundamental understanding of the crystallization mechanism of molecular sieves could be of great value to design and synthesize new molecular sieves with desirable structural properties.

As an emerging ultrathin semiconductor material, Bi2O2Se exhibits prominent performances in electronics, optoelectronics, ultrafast optics, etc. However, until now, the in-plane growth of Bi2O2Se thin films is mostly fulfilled on atomically flat mica substrates with interfacial electrostatic forces setting obstacles for Bi2O2Se transfer to fabricate functional van der Waals heterostructures. In this work, controlled growth of inclined Bi2O2Se ultrathin films is realized with apparently reduced interfacial contact areas upon mica flakes. Consequently, the transfer of Bi2O2Se could be facile by overcoming weaker electrostatic interactions. From cross-sectional characterizations at the Bi2O2Se/mica interfaces, it is found that there are no oxide buffer layers in existence for both in-plane and inclined growths, while the un-neutralized charge density is apparently decreased for inclined films. By mechanical pressing, inclined Bi2O2Se could be transferred onto SiO2/Si substrates, and back-gated Bi2O2Se field effect transistors are fabricated, outperforming previously reported in-plane Bi2O2Se devices transferred with the assistance of corrosive acids and adhesive polymers. Furthermore, Bi2O2Se/graphene heterostructures are fulfilled by a probe tip to fabricate hybrid phototransistors with pristine interfaces, exhibiting highly efficient photoresponses. The results in this work demonstrate the potential of inclined Bi2O2Se to act as a building block for prospective van der Waals heterostructures.

Strong metal-support interaction (SMSI), commonly happening between metal and metal oxide support, has drawn significant attention in heterogeneous catalysis due to its capability of enhancing the activity and stability of catalysts. Herein, the strong interaction between metal oxide and carbon supports is discovered to significantly boost the performance for electrocatalytic CO2 reduction reaction (CO2RR). A molecular engineering strategy is designed to develop undoped, N-doped, S-doped, and N,S-codoped porous carbon supports with similar physical properties (denoted as C, NC, SC, and NSC, respectively). These supports can host high-density SnO2 nanoparticles (over 60 wt. %) in a small size of ∼3.5 nm and good distribution, providing an excellent platform to understand the strong metal oxide-support interaction (SMOSI) and their influence on electrocatalytic performance. Systematic experimental and theoretical investigations discover the SMOSI between SnO2 nanoparticles and carbon supports in an order of SnO2/NSC > SnO2/NC > SnO2/SC > SnO2/C. Such SMOSI enables the effective electron transfer from carbon support to SnO2 nanoparticles, strengthening the adsorption of key reaction intermediate of CO2- and thus promoting CO2RR. With the strongest SMOSI, SnO2/NSC exhibits significantly enhanced selectivity and activity for CO2 reduction to HCOOH with a high faradaic efficiency of 94.4% and an extraordinary partial current density of 56.0 mA·cm-2 in an H-cell, outperforming the majority of Sn-based catalysts. Notably, SMOSI can simultaneously secure the active sites and thus remarkably enhance their catalytic durability, making it a promising strategy for exploring efficient and stable catalysts for diverse applications.

A first-principles approach was utilized to investigate the magnetoelectric coupling behaviour of two-dimensional BaTiO3 (001) ultrathin films with surface Ba vacancy under different strains. The total magnetic moment was suppressed when compressive strains were employed and had minimum values of 1.715 μB and 1.568 μB corresponding to uniaxial and biaxial strains, respectively; moreover, it exhibits an enhancement in the case of tensile strain. For shear strain, the magnetic moment fluctuated at ~1.78 μB. Furthermore, all partial magnetic moments and spontaneous polarization were functions of the strains except for the case of shear strain. Their conversion efficiency exhibited a regular varying tendency with increasing tensile strain. To explore electron spins, which can also be regulated, spin-orbit coupling calculations were carried out, showing that the changes in partial magnetic moments increased when the tensile strain was enhanced. Our study may pave a way for two-dimensional BaTiO3 to be applied in novel spin-based devices.

High-efficiency photocatalysts are of great importance to satisfy the requirements of green chemistry nowadays. Here we reported a novel solar-driven photocatalyst fabricated by a facile surface modification method, with the two-dimensional carboxylated zinc phthalocyanine-carboxylated C60-titanium dioxide (ZnPc-C3-TiO2) nanosheets, in which the surface modifications of ZnPc and C60 derivative were designed to extend the absorption range and promote charge separation, respectively. Benefiting from the unique structure and positive synergetic effect, the ZnPc-C3-TiO2 nanocomposite shows promising applications in selective reduction of nitroarenes for high-value-added aromatic amines under solar light. Especially, for the photocatalytic reduction of nitrobenzene to aniline, the ZnPc-C3-TiO2 nanocomposite possesses both high efficiency and selectivity (up to 99%).

Fluorescence biosensors that enable highly sensitive detection of glutathione (GSH) are in great demand for various biological investigations and early disease diagnoses. Here, we report a turn-on fluorescence nanoplatform based on fluorescent semiconducting polymer nanoparticle@MnO2 nanosheets (P-dot@MnO2) nanocomposites for rapid homogeneous determination of GSH. The near-infrared (NIR) fluorescent P-dots were prepared by doping NIR dyes into polymer matrix and then encompassed by MnO2, which resulted in a remarkable fluorescence quenching. Owing to the selective decomposition of MnO2 by GSH, the fluorescence recovery was achieved in the presence of GSH. On the basis of the target-induced turn-on fluorescence response, the developed nanoplatform can readily detect GSH with a high sensitivity up to 0.26 μM, as well as a superior specificity. Furthermore, it was successfully applied in monitoring the intracellular GSH in living cells, revealing its great potential in biomedical applications.

This work describes a novel and portable pressure-based point-of-care (POC) testing strategy for the sensitive and rapid detection of carcinoembryonic antigen (CEA) via a flexible pressure sensor constructed by three-dimensional (3D) polypyrrole (PPy) foam. Initially, platinum nanoparticles (PtNPs) were conjugated to the detection antibodies, which were used to form sandwich-type immunocomplexes with targets and capture antibodies in the reaction cell. Then, the carried PtNPs catalyzed the dissociation of hydrogen peroxide (H2O2) for the generation of oxygen (O2) in a sealed device, translating the biomolecule recognition event into gas pressure. With the increase of pressure, a flexible pressure sensor with 3D polypyrrole foam as the sensing layer was used to sensitively monitor the pressure variations in this system. Thus, the concentration of the target could be quantitatively determined by the pressure response. Under optimal conditions, the pressure-based immunosensor showed good sensing performance for CEA in the dynamic working range from 0.2 to 60 ng/mL with a detection limit of 0.13 ng/mL. The reproducibility, specificity, and accuracy compared with commercial enzyme-linked immunosorbent assay (ELISA) kit were also acceptable. Therefore, this work provides a promising approach for developing portable and sensitive POC testing in the future.

The rational design of nanoplatforms to bypass reticuloendothelial system (RES) clearance, enhance spatiotemporal controllability, and boost host immune responses to achieve synergized tumor-targeted therapeutic purpose is highly desired. Herein, a biomimetic nanosystem is developed for tumor-targeted in situ delivery of singlet oxygen (1O2) and carbon monoxide (CO) in response to exogenous stimulus ultrasound (US) and endogenous stimulus hydrogen peroxide (H2O2) in tumor microenvironment, respectively. Taking advantages of tumor homing and RES evasion abilities of the macrophage membrane coating, our designed nanosystem shows excellent accumulation at the tumor site and effective suppression of tumor growth through US/H2O2-generated 1O2 and CO to induce cell apoptosis and mitochondrial dysfunction. Furthermore, our nanosystem can induce significant tumor immunogenic death by 1O2/CO therapy, then can achieve effective immune responses and long-term immune memory through the combination of indoleamin 2,3-dioxygenase (IDO) signal blocking to effectively against tumor rechallenge and prevent lung metastasis. Taken together, the here-presented therapeutic strategy based on sonodynamic/CO therapy and IDO signaling inhibition might provide a promising perspective for synergistically treating cancer in future clinical translations.

Protein-metabolite interactions (PMIs) play important roles in various biological processes, especially in disease progression. However, due to the complexity of living cells, it is very difficult to identify specific PMIs. Herein, we chose one oncogenic factor, metadherin (MTDH), as a bait to identify its in vivo interacting metabolites in cancer cells. Cholesterol is an important metabolite and essential structural component of cell membranes. It could also drive several diseases including cancer. Interestingly, we found that cholesterol robustly interacted with MTDH and downregulated the expression of MTDH in cancer cells. Furthermore, MTDH disturbed metabolite alterations under cholesterol treatment in MTDH transduced cancer cells. Collectively, our results uncover an undescribed PMI where MTDH, as an oncogenic factor, might positively regulate cancer progression by interacting with cholesterol. This study interprets the theoretical basis of PMI-oriented cancer progression and targeting therapies in clinic.

The purposes of this study were to analyse the spatiotemporal variations in greenhouse gas diffusive fluxes at the sediment–water interface of sewage-draining rivers and natural rivers, and investigate the factors responsible for the changes in greenhouse gas diffusive fluxes. Greenhouse gas diffusive fluxes at the sediment–water interface of rivers in Tianjin city (Haihe watershed) were investigated during July and October 2014, and January and April 2015 by laboratory incubation experiments. The influence of environmental variables on greenhouse gas diffusive fluxes was evaluated by Spearman’s correlation analysis and a multiple stepwise regression analysis. Sewage-draining rivers were more seriously polluted by human sewage discharge than natural rivers. The greenhouse gas diffusive fluxes at the sediment–water interface exhibited obvious spatiotemporal variations. The mean absolute value of the CO2 diffusive fluxes was seasonally variable with spring>winter>fall>summer, while the mean absolute values of the CH4 and N2O diffusive fluxes were both higher in summer and winter, and lower in fall and spring. The annual mean values of the CO2, CH4 and N2O diffusive fluxes at the sewage-draining river sediment–water interface were − 123.26 ± 233.78 μmol m−2 h−1, 1.88 ± 6.89 μmol m−2 h−1 and 1505.03 ± 2388.46 nmol m−2 h−1, respectively, which were 1.22, 4.37 and 134.50 times those at the natural river sediment–water interface, respectively. The spatial variation of the N2O diffusive fluxes in the sewage-draining rivers and the natural rivers was the most significant. As a general rule, the more serious the river pollution was, the greater the diffusive fluxes of the greenhouse gases were. On average for the whole year, the river sediment was the sink of CO2 and the source of CH4 and N2O. There were positive correlations among the CO2, CH4 and N2O diffusive fluxes. The main influencing factor for CO2 and N2O diffusive fluxes was the water temperature of the overlying water; however, the key factors for CH4 diffusive fluxes were the Eh of the sediment and the NH4+-N of the overlying water. River sediment can be either a sink or a source of greenhouse gases, which varies in different levels of pollution and different seasons. Human sewage discharge has greatly affected the carbon and nitrogen cycling of urban rivers.

The phase instability of cesium lead halide perovskite is still a substantial challenge hindering its application. A 2D-3D all-inorganic Cs2PbI2Cl2-CsPbI2.5Br0.5 perovskite solar cell was successfully developed to address this issue. The 2D Cs2PbI2Cl2 phase distributed among the grain boundaries of the 3D CsPbI3-xBrx grains. The existence of Cs2PbI2Cl2 effectively facilitated the (100) preferential crystal orientation of the CsPbI2.5Br0.5 crystals, promoting the carrier transport. The smooth transition region between the (003)2D//(001)3D interface indicated the formation of a 2D-3D heterostructure. Due to the improved crystal quality, high uniformity, and repeatability, the efficiency of the solar cells with areas of 0.09, 1, and 2 cm2 significantly improved to 15.09%, 12.74%, and 10.01%, respectively. The power conversion efficiency (PCE) retained 95.3% of the initial efficiency after 60 days in a nitrogen atmosphere at room temperature and 80% of the initial efficiency at a humidity of 70 ± 10% relative humidity (RH) under continuous heating at 80 °C for 12 h.

Effective irrigation can maintain the vigorous photosynthetic metabolism of leaves and lay a physiological foundation for their material production. Dry matter accumulation and leaf response to light and carbon dioxide of maize under irrigation quotas of 50 mm (Q0), 90 mm (Q1), 170 mm (Q2) and 250 mm (Q3) were studied. The results showed that the dry matter accumulation were significantly increased in Q2 and Q3 treatment compared with CK at R3, R4 and R6 stages. With the increase of light intensity, the photosynthesis-light response curves of Q2 and Q3 treatments were increased the most. The apparent quantum efficiency, maximum net photosynthetic rate, light saturation point and dark respiration rate of Q2 and Q3 treatments were significantly higher than those of Q0 and Q1 treatments at V12, R1 and R3 stages. The light compensation point was apparently lower than that of Q0 and Q1 treatments. The maize photosynthesis-CO2 response curves of Q2 and Q3 treatments demonstrated the largest increase with the increase of CO2 concentration. The CO2 saturation point, maximum net photosynthetic rate and carboxylation efficiency of Q2 and Q3 treatments were significantly higher than those of Q0 and Q1 treatments. The CO2 compensation point was obviously lower than that of Q0 and Q1 treatments. The study provides an effective irrigation and management method for maize in semi-arid area of west Jilin Province, China. When the irrigation quota reached 170 mm, the dry matter accumulation of maize and the response of maize leaves to light and CO2 were both better. 170 mm could be used as the reference value of maize irrigation quota in western Jilin Province.

1,4-butanediamine (BEA) is incorporated into FASnI3 (FA=formamidinium) to develop a series of lead-free low-dimensional Dion-Jacobson-phase perovskites, (BEA)FAn-1 Snn I3n+1 . The broadness of the (BEA)FA2 Sn3 I10 band gap appears to be influenced by the structural distortion owing to high symmetry. The introduction of BEA ligand stabilizes the low-dimensional perovskite structure (formation energy ca. 106 j mol-1 ), which inhibits the oxidation of Sn2+ . The compact (BEA)FA2 Sn3 I10 dominated film enables a weakened carrier localization mechanism with a charge transfer time of only 0.36 ps among the quantum wells, resulting in a carrier diffusion length over 450 nm for electrons and 340 nm for holes, respectively. Solar cell fabrication with (BEA)FA2 Sn3 I10 delivers a power conversion efficiency (PCE) of 6.43 % with negligible hysteresis. The devices can retain over 90 % of their initial PCE after 1000 h without encapsulation under N2 environment.

Motivated by the chirality research of the hybrid halide perovskite, we reported the controllable growth of single crystals of (R)-, (S)-, and (R,S)-C6H5CH(CH3)NH3 (MBA)-based lead (Pb) halide perovskites. The crystal structures were redetermined and further refined to clarify the previously ambiguous crystal structure problems. We further investigated the chiral optical properties of these single crystals including nonlinear optical (NLO) properties and photoluminescence (PL) properties. The as-fabricated (R)- and (S)-MBAPbBr3 single crystals not only show notable circular dichroism (CD) signals in the absorption spectra but also exhibit obvious circularly polarized luminescence (CPL) characteristics. The available chiral hybrid perovskite single crystals open up the possibility to study these intrinsic chirality properties for optoelectronic applications.

Because of their attractive photoelectrical properties, perovskite-phase, CsPbX3 (X = I, Br, or Cl) materials have recently gained attention for their applications in resistive switching (RS) memor...

How 2D Ti3 C2 enhances photocatalytic efficiency remains unclear. Now, it is shown that it is graphene quantum dots (GQDs) derived from Ti3 C2 , rather than 2D Ti3 C2 itself, that play the role of co-catalyst for La2 Ti2 O7 /Ti3 C2 (LTC) composites during the photocatalytic reaction. After modification of Ti3 C2 derivatives, the photocatalytic efficiency of La2 Ti2 O7 is enhanced 16 times over pure La2 Ti2 O7 . Solid-state NMR, Raman, and HRTEM results confirm the existence of GQDs in Ti3 C2 and LTC composites. The GQDs are formed during the chemical change from Ti3 AlC2 to Ti3 C2 via HF etching, as Ti atoms are removed and unsaturated carbon bonds are left, which react with each other to form sp2 π-conjugation GQDs. 2D Ti3 C2 is completely oxidized to COx modified TiOx species, causing Ti3 C2 to lose its electrical conductivity and the role as co-catalyst. GQDs largely suppress the photogenerated charge recombination of La2 Ti2 O7 , as revealed by the photoluminescence (PL) and transient photocurrent.

A first-principles approach is utilized to study the magnetoelectric coupling induced by Fe in two-dimensional BaTiO3(001) ultrathin film. It is observed that the Fe impurity increases the total magnetic moment but suppresses the spontaneous polarization. Furthermore, the total magnetic moment of Fe replacing Ti is influenced by the distance between dopants and decreases with reducing distance. A study of spin-orbit coupling under bi-axial compressive strain shows strong magnetoelectric coupling with Ti substitution and the configuration with neighbouring Fe is more readily adjusted than that with Fe distant from each other. Meanwhile, the replacement of Ba exhibits negligible interaction between spontaneous polarization and magnetic moment. Clearly, our current work may indicate that the careful substitution of Ti with Fe atoms can realize two-dimensional BaTiO3 behaving as a multiferroic material.

The promoting effect of Ce on V-W/Ti catalyst for selective catalytic reduction (SCR) of NOx by NH3 was studied. Compared with the original V-W/Ti samples, addition of Ce contributed better NH3-SCR performance. The H2O and SO2 resistance of Ce modified V-W/Ti catalyst was improved by the different impregnation sequence of Ce. The catalysts were characterized by NH3-temperature programmed desorption (NH3-TPD), X-ray photoelectron spectroscopy (XPS), and H2-temperature programmed reduction (H2-TPR) techniques. The results showed that the impregnation sequence of W and Ce influenced the NH3 adsorption capacity of the catalysts. In comparison to 0.2V-5Ce-5W/Ti and 0.2V-(5Ce5W)/Ti, 0.2V-5W-5Ce/Ti catalyst contributed better H2O and SO2 resistance, with the highest Ce3+/(Ce4+ + Ce3+) value of 36.6%. Besides, a catalytic mechanism of SCR reactions over Ce-doped V-W/Ti catalysts was proposed.

Cell surface engineering is an emerging technology to encapsulate cells in order to enhance their functions. However, methods for reversible encapsulation of cells with abiotic functionalities are rare. Herein, we describe a phenylboronic acid based click reaction for encapsulation of single yeast cells using mesoporous silica nanoparticles (MSNs). This encapsulation does not impact natural growth of the cells and leads to a significant enhancement of cell survival in a variety of hostile environments. Owing to the glucose-responsiveness of the boronate ester bond between cell surface polysaccharides and B(OH)2-grafted MSNs, encapsulation was reversible by addition or removal of glucose. This effort offers living cells effective protection under harsh conditions and enables reversible assembling-detaching of abiotic functions.

As a powerful and sensitive tool for the characterization of zeolite building units, UV Raman spectroscopy has been used to monitor interzeolite transformation from FAU to CHA and MFI zeolites. The results show that the behavior of double 6-membered rings (D6Rs) in the FAU zeolite framework plays an important role during the formation of the target product in the interzeolite transformation. For the transformation of FAU to CHA, because both zeolites contain the same D6R units, direct transformation occurs, in which the D6Rs were largely unchanged. In contrast, for the transformation of FAU to MFI, the D6Rs can be divided into two single 6-membered rings (S6Rs), which further assembled into the MFI structure. In this crystallization, 5-membered rings (5Rs) are only observed in the MFI framework formation, suggesting that the basic building units in the transformation of FAU to MFI are S6Rs rather than 5Rs. These insights will be helpful for further understanding of the interzeolite transformation.

The matrix plays a prominent role in expanding the ability of matrix assisted laser desorption/ionization mass spectrometry (MALDI MS). However, on account of the unclarity of necessary properties of the matrix in MALDI MS, development of a new matrix is still in the exploratory stage and lacks systematic theoretical guidance. Meanwhile, most of the existing matrices are unable to simultaneously detect various high-molecular-weight (high-MW) lipids including (poly-)phosphoinositides, cardiolipins, and gangliosides. In this study, we have successfully screened and optimized the application of commercially available IR-780 as a novel matrix for simultaneously profiling and imaging high-MW lipids in brain tissues by MALDI MS for the first time. The properties of IR-780 related to the matrix of MALDI MS, mainly including the optical properties (UV absorption, fluorescence emission, and photothermal efficiency), proton affinity, collision cross-sections (CCSs), salt-tolerance ability, and homogeneity, were comprehensively characterized, which demonstrated that high photothermal ability and large CCSs might guarantee the superior performance of IR-780 as matrix for the analysis of high-MW lipids in biological samples. This work provided some references for the development of a novel matrix, and especially, the concept of CCS was first introduced as a parameter for the development of a matrix. In addition, the simultaneous identification and imaging of endogenous high-MW lipids in rat brain tissues subjected to traumatic brain injury were successfully performed.

Tumor microenvironment responsive multimodal synergistic theranostic strategies can significantly improve the therapeutic efficacy while avoiding severe side effects. Inspired by the fact that special morphology could enhance photothermal conversion efficiency (PCE) and cellular delivery, we developed an acidic tumor microenvironment responsive shape-reversal metal-organic virus-inspired nanodrug for enhancing near-infrared (NIR)-II PCE, increasing cell adhesion, and activating tumor targeting. First, a NIR-I fluorescence probe (IR825), a chemo-drug (pemetrexed, PEM), and a rare-earth metal ion (Nd(III)) were chosen to synthesize a virus-like nanodrug

Metallic lithium affords the highest theoretical capacity and lowest electrochemical potential and is viewed as a leading contender as an anode for high-energy-density rechargeable batteries. However, the poor wettability of molten lithium does not allow it to spread across the surface of lithiophobic substrates, hindering the production and application of this anode. Here we report a general chemical strategy to overcome this dilemma by reacting molten lithium with functional organic coatings or elemental additives. The Gibbs formation energy and newly formed chemical bonds are found to be the governing factor for the wetting behavior. As a result of the improved wettability, a series of ultrathin lithium of 10–20 μm thick is obtained together with impressive electrochemical performance in lithium metal batteries. These findings provide an overall guide for tuning the wettability of molten lithium and offer an affordable strategy for the large-scale production of ultrathin lithium, and could be further extended to other alkali metals, such as sodium and potassium., Molten lithium cannot spread onto the lithiophobic substrate, hindering the production and application of lithium metal anodes. Here, the authors show a general chemical strategy to tune the wettability by forming new chemical bonds through the reactions with various organic coatings or elemental additives.

As a promising photocatalyst, the large band gap of TiO2 imposes restriction on its light absorption in the visible region, making it less application in industrial fields. Herein, we design a facile solvothermal method to fabricate colorful defective TiO2-x microspheres with controllable morphological and porous structure, large specific surface area and tunable band gap on the basis of the Schiff base reaction between acetylacetone and ethylenediamine which produce bis(acetylacetone)ethylenediamine (acacen). The acacen, as a tetradentate Schiff-base ligand, has four binding sites which can stabilize titanium centers to produce titanium Schiff base complexes. The color of TiO2-x-Ti(acacen)y complexes changes from yellowish to brown and red with the variation of the acacen ligand, and the corresponding bandgap narrows from 3.25 eV to 2.16 eV as a result of the newly formed Ti3+ and oxygen vacancies (Vo) in the TiO2 lattice. In addition, red TiO2-x microspheres cooperating with titanium Schiff base complex demonstrate high photocatalytic efficiency in methylene blue under visible light as well as hydroxyl radical generation in contrast to yellowish TiO2 microspheres, revealing the significance of this strategy for morphological and bandgap manipulation in defective TiO2-x nanomaterials for high-performance photocatalysis.

Ionothermal synthesis has been widely used for the preparation of aluminophosphate-based molecular sieves, coordination polymers, metal-organic frameworks, and covalent organic frameworks. However, this method is still challenging for synthesis of silica-based zeolites. Herein, we show a generalized ionothermal route to synthesize silica-based zeolites with MTT, TON, ITW, and MFI structures in the presence of NH4F as a mineralizing agent and ionic liquid as a solvent and/or structure directing agent. The presence of a suitable amount of NH4F plays a key role for the successful synthesis of these silica-based zeolites. This methodology might open a pathway to ionthermally synthesize silica-based zeolites.

The transformation of digital computers from bulky machines to portable systems has been enabled by new materials and advanced processing technologies that allow ultrahigh integration of solid-state electronic switching devices. As this conventional scaling pathway has approached atomic-scale dimensions, the constituent nanomaterials (such as SiO2 gate dielectrics, poly-Si floating gates and Co–Cr–Pt ferromagnetic alloys) increasingly possess properties that are dominated by quantum physics. In parallel, quantum information science has emerged as an alternative to conventional transistor technology, promising new paradigms in computation, communication and sensing. The convergence between quantum materials properties and prototype quantum devices is especially apparent in the field of 2D materials, which offer a broad range of materials properties, high flexibility in fabrication pathways and the ability to form artificial states of quantum matter. In this Review, we discuss the quantum properties and potential of 2D materials as solid-state platforms for quantum-dot qubits, single-photon emitters, superconducting qubits and topological quantum computing elements. By focusing on the interplay between quantum physics and materials science, we identify key opportunities and challenges for the use of 2D materials in the field of quantum information science. 2D materials exhibit diverse properties and can be integrated in heterostructures: this makes them ideal platforms for quantum information science. This Review surveys recent progress and identifies future opportunities for 2D materials as quantum-dot qubits, single-photon emitters, superconducting qubits and topological quantum computing elements.

Currently, the synthesis of pure silica zeolites always requires the presence of organic structure-directing agents (OSDAs), which direct the assembly pathway and ultimately fill the pore space. A sustainable route is now reported for synthesizing pure silica zeolites in the absence of OSDAs from a combined strategy of zeolite seeding and alcohol filling, where the zeolite seeds direct crystallization of zeolite crystals from amorphous silica, while the alcohol is served as pore filling in the zeolites. Very importantly, the alcohol could be fully washed out from zeolite pores by water at room temperature, which completely avoids calcination at high temperature for removal of OSDAs in the synthesis of pure silica zeolites.

Line matching plays an important role in vision localization and three-dimensional reconstruction of building structures. The conventional method of line matching is not effective for proce...

All-inorganic perovskite materials emerge to be potential promising candidates for photoelectric applications. However, their instability to moisture has seriously limited future applications. It is imperative to develop new fabrication methods to make the perovskite films moisture-tolerant. In this work, it is demonstrated that both crystallinity and photoelectronic performance of the CsPbI3-xBrx (x < 1) perovskite were enhanced with the existence of excess CsBr and employing moisture treatment. An intermediate product of CsI1-yBry/CsPbI3-xBrx was obtained by using an extra amount of CsBr, and the structural evolution toward a uniform CsPbI3-zBrz layer (as the Br- incorporation, the mole ratio increases from x to z) was initiated by moisture treatment, forming new (PbX6)4- octahedra with the bonding of CsI1-yBry to Pb2+. Attributed to the homogeneity of the stoichiometry and crystallinity, the photovoltaic performance of the moisture-treated perovskite films was improved, with the open-circuit voltage increased from 0.97 to 1.10 V and the power conversion efficiency from 10.89 to 13.09%.

We propose a periodic table for quadrilateral tetra-atomic molecules. Each molecule consists of four atoms, and the geometric shapes of these molecules are studied by ab initio calculations. It is found that by increasing the valence electron numbers, strong periodicity appears with many molecular properties. The periodic table for the quadrilateral tetra-atomic molecules is considered as an extension of Mendeleev's periodic table. It can also be used for estimating the unknown properties of tetra-atomic molecules.

An experimental study is carried out for waves passing an isolated reef terrain in a wave tank. A three-dimensional model of a representative and isolated reef terrain in the West Pacific is built. Random wave trains with various periods and wave heights are generated by a wave maker using the improved JONSWAP spectrum. It is observed that there are different kinds of generation processes and waveforms of freak waves. The freak wave factor Hm/Hs (where Hm is the maximum wave height of wave series, and Hs is significant wave height) is analyzed in detail, in terms of the skewness, kurtosis and water depth, as well as the relationship between freak wave height Hfr and skewness. The freak wave factor Hm/Hs is found to be in positive correlation with the kurtosis, while larger Hfr tends to be related with bigger skewness. The rapid variation of water depth, such as slope and seamount, contributes to the occurrence probability of freak waves.

In this paper a direct coupling analysis method (DCAM) of hydroelastic responses of a very large floating structures (VLFS) in complicated geographical environment is presented. In this method the three-dimensional hydroelasticity theory of floating bodies is combined with the shallow water wave theory, to allow for proper description of the influence of uneven seabed and sheltering effect of islands on the hydroelastic responses of a VLFS deployed near island and reefs in shallow sea. This method and the numerical procedures were verified and validated by comparison between the predictions and the model test results of a 3-module VLFS and an 8-module VLFS in two simulated shallow sea regions with different seabed topography.

In this work, we presented a detailed evaluation of Ru/TiO2 (P25) catalysts for the catalytic oxidation of (chloro)-aromatics. The model catalysts were synthesized through wet impregnation. Catalytic evaluations, as well as ICP, BET, XRD and TEM analyses, were conducted. The results indicated that RuO2 tended to be distributed on the rutile phase of TiO2, leading to an inhomogeneous distribution. These Ru/TiO2 catalysts were very active, especially for chlorobenzene oxidation. The conversions of benzene and chlorobenzene were both suppressed by the introduction of additional water. But the amount of polychlorinated benzenes as by-products was also reduced. However, the activity of the catalyst significantly decreased with an increase in calcination temperature, suggesting that the thermal stability of the catalyst still needed to be improved.

In this study, the Ag/CeO2 catalysts with three different morphologies of ceria nanocubes (CeO2-c), nanorods (CeO2-r) and nano-octahedra (CeO2-o) as supports were prepared by wet impregnation. Various characterizations such as XRD, BET, TEM/HRTEM, HAADF-STEM, XPS and H2-TPR were conducted, and a four step catalytic transformation was accordingly proposed. It was found that Ag/CeO2-c showed much more metallic Ag, active oxygen species and higher reducibility than those of Ag/CeO2-r and Ag/CeO2-o mainly due to the morphology effect. Ag/CeO2 and CeO2 catalysts were evaluated in the oxidation of ethyl acetate, and their catalytic activities were in the sequence of Ag/CeO2-c > Ag/CeO2-r > CeO2-r > CeO2-c > Ag/CeO2-o > CeO2-o. Besides, in-situ FTIR results revealed that the organic species on the catalyst surface were mainly acetates and adsorbed ethyl acetate for Ag/CeO2-c and CeO2-c, respectively, suggesting that addition of Ag promoted the complete oxidation of ethyl acetate.

Cavities are widely spread inside the polyetherimide which is a super engineering plastic. As the main source of partial discharge, they may lead to the tree-like breakdown and insulation failure of material. With the 30 MHz ultrasonic scanning microscope, the cavities of single sample and batch samples are identified and characterized. Small cavities (1–5 pixels) occupy more than 95% of all cavities for a typical sample. The mean area, total area and cavity number of each batch are closer to normal distribution. By the improved experimental system, the breakdown characteristic and insulation life of samples are tested. The cavities scanning from the front and back sides increased by 31% and 41% respectively after breakdown. The normalized insulation life is reduced by nearly 36 times as the mean cavity area increased by only 2 times.

Borophene (the first two-dimensional (2D) allotrope of boron) is emerging as a groundbreaking system for boron-based chemistry and, more broadly, the field of low-dimensional materials. Exploration of the phase space for growth is critical because borophene is a synthetic 2D material that does not have a bulk layered counterpart and thus cannot be isolated via exfoliation methods. Herein, we report synthesis of borophene on Au(111) substrates. Unlike previously studied growth on Ag substrates, boron diffuses into Au at elevated temperatures and segregates to the surface to form borophene islands as the substrate cools. These observations are supported by ab initio modeling of interstitial boron diffusion into the Au lattice. Borophene synthesis also modifies the surface reconstruction of the Au(111) substrate, resulting in a trigonal network that templates growth at low coverage. This initial growth is composed of discrete borophene nanoclusters, whose shape and size are consistent with theoretical predictions. As the concentration of boron increases, nanotemplating breaks down and larger borophene islands are observed. Spectroscopic measurements reveal that borophene grown on Au(111) possesses a metallic electronic structure, suggesting potential applications in 2D plasmonics, superconductivity, interconnects, electrodes, and transparent conductors.

The syndepositional tectonic evolution and sequence stratigraphic architecture of the Paleogene Lingshui Sag, Qiongdongnan Basin, South China Sea, are investigated with seismic profiles, boreholes ...

The nanoplatform of synergistic chemo-photothermal therapy has superior advantages on antitumor. It is urgently needed to explore novel nanocarrier for improving photothermal performance in drug delivery process. Herein, we synthesized polydopamine doped mesoporous silica-coated reduced graphene oxide (rGO/MSN/PDA) by simply adding dopamine hydrochloride into the oil-water biphasic reaction system as a multifunctional drug carrier for anticancer treatment, which combines chemotherapy and photothermal therapy. The rGO/MSN/PDA showed nearly twice the photothermal conversion efficiency of mesoporous silica-coated graphene oxide (GO/MSN) due to the reduction of GO and doping with PDA. In addition, the rGO/MSN/PDA showed pH-response DOX release abilities, which means higher release of DOX in tumor cells. The cell experiments in vitro proved that rGO/MSN/PDA with better biocompatibility compare to GO/MSN might offer a promising tool for improving the therapeutic effects of hepatocellular carcinoma cells through synergistic chemo-photothermal therapy.

Recently reported black phosphorus quantum dots (BPQDs) possess unique photocatalysis activities. However, the environmental instability accompanied by a hypoxic tumor microenvironment (TME) seriously hindered the bioapplications of BPQDs, especially in oxygen-dependent photodynamic therapy (PDT). Here, we construct a hepatocellular carcinoma (HCC)-specific targeting aptamer "TLS11a"-decorated BPQDs-hybridized nanocatalyst, which can specifically target HCC tumor cells and self-compensate oxygen (O