Unconventional hexagonal open Prussian blue analog structures.

Prussian blue analogs (PBAs), as a classical kind of microporous materials, have attracted substantial interests considering their well-defined framework structures, unique physicochemical properties and low cost. However, PBAs typically adopt cubic structure that features small pore size and low specific surface area, which greatly limits their practical applications in various fields ranging from gas adsorption/separation to energy conversion/storage and biomedical treatments. Here we report the facile and general synthesis of unconventional hexagonal open PBA structures.

Enabling Multicolor Information Encryption: Oleylammonium-Halide-Assisted Reversible Phase Conversion between CsPbX and CsPbX Nanocrystals.

Recently, halide perovskites have been recognized for their thermochromic characteristics, showing significant potential in information encryption applications. However, the limited luminescence color gamut hinders the encryption of complex multicolor information. Herein, for the first time, multicolor thermochromic perovskites with luminescence covering the entire visible spectrum have been designed.

Regulating the Intralayer Cation Disorder in Layered Lithium-Rich Cathodes to Improve Cycle Performance.

The Li/Mn ordered structure of lithium-rich (LR) cathodes leads to the heterogeneous LiMnO and LiTMO components, readily triggering structural degeneration and performance degradation in long-term cycling. However, the lack of guiding principles for promoting cation disorder within the transition metal (TM) layers has posed a persistent challenge in designing homogeneous layered LR cathodes. Herein, the (Li + Mn) content in the TM layer as a criterion for the design of cation-disordered layered LR cathodes is proposed.

Site-Selective Growth of fcc-2H-fcc Copper on Unconventional Phase Metal Nanomaterials for Highly Efficient Tandem CO Electroreduction.

Copper (Cu) nanomaterials are a unique kind of electrocatalysts for high-value multi-carbon production in carbon dioxide reduction reaction (CORR), which holds enormous potential in attaining carbon neutrality. However, phase engineering of Cu nanomaterials remains challenging, especially for the construction of unconventional phase Cu-based asymmetric heteronanostructures. Here the site-selective growth of Cu on unusual phase gold (Au) nanorods, obtaining three kinds of heterophase fcc-2H-fcc Au-Cu heteronanostructures is reported.

Phase Engineering of Zirconium MOFs Enables Efficient Osmotic Energy Conversion: Structural Evolution Unveiled by Direct Imaging.

Creating structural defects in a controlled manner within metal-organic frameworks (MOFs) poses a significant challenge for synthesis, and concurrently, identifying the types and distributions of these defects is also a formidable task for characterization. In this study, we demonstrate that by employing 2-sulfonylterephthalic acid as the ligand for synthesizing Zr (or Hf)-based MOFs, a crystal phase transformation from the common topology to the rare topology can be easily facilitated using a straightforward mixed-solvent strategy. The phase, characterized by an extensively open framework, can be considered a derivative of the phase, generated through the introduction of missing-cluster defects.

Spatial-temporal evolution of population aging in the yangtze river delta urban agglomeration of China.

The Yangtze River Delta urban agglomeration (YRDUA) is China's most representative region with remarkable economic development vitality. The purpose of this study is to provide valuable data analysis to actively respond to the population aging in China. We mainly focus on the spatial and temporal evolution of population aging in YRDUA from 2000 to 2020 using city-level population data.

Steering the Selectivity of Carbon Dioxide Electroreduction from Single-Carbon to Multicarbon Products on Metal-Organic Frameworks via Facet Engineering.

Although metal-organic frameworks (MOFs) have attracted more attention for the electrocatalytic CO reduction reaction (CORR), obtaining multicarbon products with a high Faradaic efficiency (FE) remains challenging, especially under neutral conditions. Here, we report the controlled synthesis of stable Cu(I) 5-mercapto-1-methyltetrazole framework (Cu-MMT) nanostructures with different facets by rationally modulating the reaction solvents. Significantly, Cu-MMT nanostructures with (001) facets are acquired using isopropanol as a solvent, which favor multicarbon production with an FE of 73.

Spin coating epitaxial heterodimensional tin perovskites for light-emitting diodes.

Environmentally friendly tin (Sn) perovskites have received considerable attention due to their great potential for replacing their toxic lead counterparts in applications of photovoltaics and light-emitting diodes (LEDs). However, the device performance of Sn perovskites lags far behind that of lead perovskites, and the highest reported external quantum efficiencies of near-infrared Sn perovskite LEDs are below 10%. The poor performance stems mainly from the numerous defects within Sn perovskite crystallites and grain boundaries, leading to serious non-radiative recombination.

Heterostructured Bimetallic MOF-on-MOF Architectures for Efficient Oxygen Evolution Reaction.

Electron modulation presents a captivating approach to fabricate efficient electrocatalysts for the oxygen evolution reaction (OER), yet it remains a challenging undertaking. In this study, an effective strategy is proposed to regulate the electronic structure of metal-organic frameworks (MOFs) by the construction of MOF-on-MOF heterogeneous architectures. As a representative heterogeneous architectures, MOF-74 on MOF-274 hybrids are in situ prepared on 3D metal substrates (NiFe alloy foam (NFF)) via a two-step self-assembly method, resulting in MOF-(74 + 274)@NFF.

A Customized Hydrophobic Porous Shell for MOF-5.

The susceptibility to moisture of metal-organic frameworks (MOFs) is a critical bottleneck for their wider practical application. Constructing core-shell composites has been postulated as an effective strategy for enhancing moisture resistance, but for fragile MOFs this has rarely been accomplished. We report herein, for the first time, the construction of a customized hydrophobic porous shell, NTU-COF, on the particularly fragile MOF-5 by a "Plug-Socket Anchoring" strategy.

Three-dimensional inhomogeneity of zeolite structure and composition revealed by electron ptychography.

Structural and compositional inhomogeneity is common in zeolites and considerably affects their properties. Thickness-limited lateral resolution, lack of depth resolution, and electron dose-constrained focusing limit local structural studies of zeolites in conventional transmission electron microscopy (TEM). We demonstrate that a multislice ptychography method based on four-dimensional scanning TEM (4D-STEM) data can overcome these limitations.

Topological Isomerism in Three-Dimensional Covalent Organic Frameworks.

Although isomerism is a typical and significant phenomenon in organic chemistry, it is rarely found in covalent organic framework (COF) materials. Herein, for the first time, we report a controllable synthesis of topological isomers in three-dimensional COFs via a distinctive tetrahedral building unit under different solvents. Based on this strategy, both isomers with a or net (termed JUC-620 and JUC-621) have been obtained, and their structures are determined by combining powder X-ray diffraction and transmission electron microscopy.

Interface Density Engineering on Heterogeneous Molybdenum Dichalcogenides Enabling Highly Efficient Hydrogen Evolution Catalysis and Sodium Ion Storage.

Constructing active heterointerfaces is powerful to enhance the electrochemical performances of transition metal dichalcogenides, but the interface density regulation remains a huge challenge. Herein, MoO /MoS heterogeneous nanorods are encapsulated in nitrogen and sulfur co-doped carbon matrix (MoO /MoS @NSC) by controllable sulfidation. MoO and MoS are coupled intimately at atomic level, forming the MoO /MoS heterointerfaces with different distribution density.

Three-Dimensional Covalent Organic Frameworks with Ultra-Large Pores for Highly Efficient Photocatalysis.

Benefiting from their unique structural merits, three-dimensional (3D) large-pore COF materials demonstrate high surface areas and interconnected large channels, which makes these materials promising in practical applications. Unfortunately, functionalization strategies and application research are still absent in these structures. To this end, a series of functional 3D -topologized COFs are designed based on porphyrin or metalloporphyrin moieties, named JUC-640-M (M = Co, Ni, or H).

Ground-State Spin Dynamics in Kagome-Lattice Titanium Fluorides.

Many quantum magnetic materials suffer from structural imperfections. The effects of structural disorder on bulk properties are difficult to assess systematically from a chemical perspective due to the complexities of chemical synthesis. The recently reported S = 1/2 kagome lattice antiferromagnet, (CHNH)NaTiF, , with highly symmetric kagome layers and disordered interlayer methylammonium cations, shows no magnetic ordering down to 0.

Chemically Stable Guanidinium Covalent Organic Framework for the Efficient Capture of Low-Concentration Iodine at High Temperatures.

The capture of radioactive I vapor from nuclear waste under industrial operating conditions remains a challenging task, as the practical industrial conditions of high temperature (≥150 °C) and low I concentration (∼150 ppmv) are unfavorable for I adsorption. We report a novel guanidinium-based covalent organic framework (COF), termed TGDM, which can efficiently capture I under industrial operating conditions. At 150 °C and 150 ppmv I, TGDM exhibits an I uptake of ∼30 wt %, which is significantly higher than that of the industrial silver-based adsorbents such as Ag@MOR (17 wt %) currently used in the nuclear fuel reprocessing industry.

Cryogenic Focused Ion Beam Enables Atomic-Resolution Imaging of Local Structures in Highly Sensitive Bulk Crystals and Devices.

With the development of ultralow-dose (scanning) transmission electron microscopy ((S)TEM) techniques, atomic-resolution imaging of highly sensitive nanomaterials has recently become possible. However, applying these techniques to the study of sensitive bulk materials remains challenging due to the lack of suitable specimen preparation methods. We report that cryogenic focused ion beam (cryo-FIB) can provide a solution to this challenge.

Unconventional Doping Effect Leads to Ultrahigh Average Thermoelectric Power Factor in Cu SbSe -Based Composites.

Thermoelectric materials are typically highly degenerate semiconductors, which require high carrier concentration. However, the efficiency of conventional doping by replacing host atoms with alien ones is restricted by solubility limit, and, more unfavorably, such a doping method is likely to cause strong charge-carrier scattering at ambient temperature, leading to deteriorated electrical performance. Here, an unconventional doping strategy is proposed, where a small trace of alien atoms is used to stabilize cation vacancies in Cu SbSe  by compositing with CuAlSe , in which the cation vacancies rather than the alien atoms provide a high density of holes.

Empirical Investigation on the Characteristics and Perceived Value of Patients in Medical Treatment Seeking: In-Depth Research in Zhejiang Province of China.

Background: Patient Perceived Value (PPV) provides a valuable perspective to explain why the government reforms on health system in terms of functional medical treatment performance improvement did not decrease the crowded waiting line or increased patient satisfaction in China.

Methods: Questionnaires comprising seven constructs were sent to patients from seven highly recognized hospitals in Zhejiang Province of China. It was collected via face-by-face in a twelve-month period (2019), and 2586 valid data were collected for SPSS statistic accordingly.

In-depth learning of automatic segmentation of shoulder joint magnetic resonance images based on convolutional neural networks.

Objective: Magnetic resonance imaging (MRI) is gradually replacing computed tomography (CT) in the examination of bones and joints. The accurate and automatic segmentation of the bone structure in the MRI of the shoulder joint is essential for the measurement and diagnosis of bone injuries and diseases. The existing bone segmentation algorithms cannot achieve automatic segmentation without any prior knowledge, and their versatility and accuracy are relatively low.

Modifying Ionic Membranes with Carbon Dots Enables Direct Production of High-Purity Hydrogen through Water Electrolysis.

Traditional electrolysis of water produces hydrogen with a purity of ∼98%. Using ion transport membranes to prevent the migration of oxygen (O) from the anode to the cathode, the purity of H can be increased to ∼99.8%, but it still cannot fulfill the requirement for use in fuel cells (>99.