Synthesis of nanoporous graphenes via decarboxylation reaction.

Two kinds of C-C bonded crystalline nanoporous graphenes (NPGs) have been synthesized by using a newly developed decarboxylation reaction. Both NPGs show good electrocatalytic oxygen evolution reaction (OER) activities. The clear pore-edge structures of the synthesized NPGs provide an ideal platform for further OER investigations.

3D Graphene Frameworks/Co3 O4 Composites Electrode for High-Performance Supercapacitor and Enzymeless Glucose Detection.

3D graphene frameworks/Co3 O4 composites are produced by the thermal explosion method, in which the generation of Co3 O4 nanoparticles, reduction of graphene oxide, and creation of 3D frameworks are simultaneously completed. The process prevents the agglomeration of Co3 O4 particles effectively, resulting in monodispersed Co3 O4 nanoparticles scattered on the 3D graphene frameworks evenly. The prepared 3D graphene frameworks/Co3 O4 composites used as electrodes for supercapacitor display a definite improvement on electrochemical performance with high specific capacitance (≈1765 F g-1 at a current density of 1 A g-1 ), good rate performance (≈1266 F g-1 at a current density of 20 A g-1 ), and excellent stability (≈93% maintenance of specific capacitance at a constant current density of 10 A g-1 after 5000 cycles). In addition, the composites are also employed as nonenzymatic sensors for the electrochemical detection of glucose, which exhibit high sensitivity (122.16 µA mM -1  cm-2 ) and noteworthy lower detection limit (157 × 10-9 M, S/N = 3). Therefore, the authors expect that the 3D graphene frameworks/Co3 O4 composites described here would possess potential applications as the electrode materials in supercapacitors and nonenzymatic detection of glucose.

Transcription of G-quartet supramolecular aggregates into hierarchical mesoporous silica nanotubes.

The use of 5-guanosine monophosphate (GMP) with Sr(2+) ions to form G-quadruplex bundles as supramolecular templates for the preparation of hierarchical mesoporous silica nanotube materials is reported here, and some mesopores with a diameter of 4-22 nm were obtained. Furthermore, some mesopore channels which run perpendicularly to the center axis of the tube and penetrate right through the outer wall of the nanotubes were achieved by removing the templates. Besides, porous hollow silica spheres were obtained by changing some of the reaction conditions during the process of preparation. Their structures are stable even after high temperature calcination. A formation mechanism was proposed and discussed, and their structures were characterized using a number of means including X-ray diffraction, IR spectra, N2 adsorption-desorption isotherms, scanning electron microscopy (SEM) and transmission electron microscopy (TEM).

A cationic azobenzene-surfactant-modified graphene hybrid: unique photoresponse and electrochemical behavior.

Surfactant-modified graphene hybrids containing azobenzene groups were for the first time prepared, and the electrochemical performance was investigated. The hybrids were obtained by electrostatic interactions between cationic azobenzene-surfactants and negatively charged graphene oxide in water. The electrostatic interactions, chemical structure and photoresponse of the hybrids were measured by using zeta potential values, fluorescence spectra, FTIR, XPS, XRD, SEM, UV-Vis absorption, AFM and Raman spectra. The electrochemical performance was estimated using cyclic voltammetry. The results show that strong electrostatic interactions exist between the azobenzene surfactants and graphene oxide. Notably, this azobenzene-graphene hybrid can self-assemble into aggregation structures in aqueous solution. Besides, the self-assembly can be reversibly controlled by ultraviolet light (365 nm) and blue light (455 nm) irradiation. This process is driven by the photoinduced polarity change of the cationic azobenzene surfactant and is responsible for the graphene hybrids' electrochemical performance. It is the first example of the reversible self-assembly of graphene driven by light irradiation.

A novel aptameric nanobiosensor based on the self-assembled DNA-MoS2 nanosheet architecture for biomolecule detection.

We have developed a novel fluorescence-activated DNA-MoS2 nanosheet biosensor for detecting biomolecular targets such as proteins and small molecules based on the self-assembled architecture of a DNA aptamer and a MoS2 nanosheet. The proposed design is simple to prepare and exhibits low background interference, high sensitivity and rapid response.

Macroscopic, free-standing Ag-reduced, graphene oxide Janus films prepared by evaporation-induced self-assembly.

A facile, efficient, and unique self-assembly process for the preparation of the macroscopic, free-standing, Ag-reduced, graphene oxide (Ag-RGO) Janus films, which exhibit a unique asymmetry of their two surfaces with macroscopic dimensions, is presented. A novel strategy using an evaporation-induced, self-assembly (EISA) process is shown to be a powerful and flexible method for synthesizing well-defined Janus thin films.