Reinforcing 2D Single-Crystal BiOCO with Additional Interlayer Carbonates by CO-Assisted Solid-to-Solid Phase Transition.

A facile gaseous CO mediated solid-to-solid transformation principle is adopted to insert additional CO anions into the thin single-crystal nanosheets of BiOCO, which is built of periodic arrays of intrinsic CO anions and (BiO) layers. The additional CO anions create abundant defects. The BiOCO nanosheets with rich interlayer CO exhibit superior electronic properties and charge transfer kinetics than the pristine single-crystal 2D BiOCO and display enhanced catalytic activity in photocatalytic CO reduction reaction and the photocatalytic oxidative degradation of organic pollutants.

Visible to near-infrared photodetector with novel optoelectronic performance based on graphene/S-doped InSe heterostructure on h-BN substrate.

van der Waals heterostructures of two-dimensional (2D) materials have attracted considerable attention due to their flexibility in the design of new functional devices. Despite numerous studies on graphene/2D semiconductor heterostructures, their optoelectronic applications are significantly hindered because of several disadvantages, such as large band gaps and chemical instability. In this work, we demonstrate the fabrication of graphene/S-doped InSe heterostructure photodetectors with excellent photoresponse performance, and this is attributed to the moderate band gap and band gap engineering by element doping of InSe as well as the high carrier mobility of graphene.

One-step preparation of single-layered graphene quantum dots for the detection of Fe.

Single-layer graphene quantum dots are highly desirable while their facile and controllable preparations remain challenging. Herein, single-layered graphene quantum dots (sl-GQDs) were developed via a facile one-step hydrothermal synthesis, with citric acid and β-cyclodextrin (CD) as starting materials. The sl-GQDs decorated with CD molecules emit green fluorescence with a quantum yield of 5.

Directed assembly of fullerene on modified Au(111) electrodes.

Here we show a conceptual approach to realize the scanning tunneling microscopy based induced-assembly of fullerene (C60) molecules on top of a buffer organic adlayer at room temperature in a solution environment. The realization of spatially-defined C60 assembly is attributed to the modulation of substrate-molecular interactions with the assistance of a buffer layer.

Low energy consumption vortex wave flow membrane bioreactor.

In order to reduce the energy consumption and membrane fouling of the conventional membrane bioreactor (MBR), a kind of low energy consumption vortex wave flow MBR was exploited based on the combination of biofilm process and membrane filtration process, as well as the vortex wave flow technique. The experimental results showed that the vortex wave flow state in the membrane module could be formed when the Reynolds number (Re) of liquid was adjusted between 450 and 1,050, and the membrane flux declined more slowly in the vortex wave flow state than those in the laminar flow state and turbulent flow state. The MBR system was used to treat domestic wastewater under the condition of vortex wave flow state for 30 days.

Simultaneous construction of two linkages for the on-surface synthesis of imine-boroxine hybrid covalent organic frameworks.

The orthogonality between the Schiff base reaction and the boronic acid dehydration reaction is explored during the on-surface synthesis process. By activating the above two reactions in one-step and employing asymmetrical substituted monomers and the 3-fold symmetric monomer 1,3,5-tris(4-aminophenyl)benzene (TAPB), highly ordered imine-boroxine hybrid single-layered covalent organic frameworks (sCOFs) have been successfully constructed on HOPG by a gas-solid interface reaction method and characterized by scanning tunnelling microscopy (STM). In particular, the reaction between the -substituted monomer and TAPB generates sCOFB with a windmill structure, which is the first sCOF with surface chirality so far reported.

Fabrication of europium-doped silica optical fiber with high Verdet constant.

A europium-doped (Eu-doped) silica optical fiber is fabricated using modified chemical vapor deposition (MCVD) technology. Europium fluoride (EuF) material is introduced into the fiber core with a high temperature vaporizing technique. Its concentration is approximately 0.

Fabrication of bilayer tetrathiafulvalene integrated surface covalent organic frameworks.

A bilayer covalent organic framework (COF) of TTF-based building blocks was obtained by imine reaction between tetrathiafulvalene tetraaldehyde (4ATTF) and p-phenylenediamine (PPDA). Direct evidence for the eclipsed stacking of bilayer structure via π-π interaction between TTF units is provided by high resolution scanning tunneling microscopy.

Substrate Orientation Effect in the On-Surface Synthesis of Tetrathiafulvalene-Integrated Single-Layer Covalent Organic Frameworks.

The on-surface reactions of tetrathiafulvalene equipped with four benzaldehyde groups (4ATTF) and ditopic diamine molecules are investigated. 4ATTF tends to form large-scale-ordered rhombus structures when reacted with p-phenylenediamine (PPDA). A longer ditopic diamine molecule, 1,1'-biphenyl-4,4'-diamine dihydrochloride (BPDA), causes the domain size of the regular rhombus structure to decrease and triangular and irregular rhombus structures to appear upon reaction with 4ATTF.

Electrostatic-interaction-induced molecular deposition of a hybrid bilayer on Au(111): a scanning tunneling microscopy study.

Hybrid bilayers consisting of 8-hydroxypyrene-1,3,6-trisulfonic acid trisodium salt (HPTS) and meso-tetra(4-pyridyl)porphine (TPyP) have been successfully constructed on Au(111) and investigated by electrochemical scanning tunneling microscopy (ECSTM). Under the guidance of the electrostatic interaction between negatively charged sulfonate groups and positively charged pyridyl groups, the underlying HPTS arrays act as templates for the deposition of cationic TPyPs, forming two types of TPyP/HPTS complex bilayers. The present work provides a feasible way to fabricate hybrid multilayers on the electrode surface via electrostatic interaction, which has great significance for the design of molecular nanodevices.