Three-dimensional Honeycomb-like Structure Research Articles

Honeycomb-like nickel oxide-reduced graphene oxide based sensor for the electrochemical tracking of norepinephrine in neuronal cells

Highly sensitive and specific detection and monitoring of trace norepinephrine (NE) in biological fluids and neuronal cell lines is essential for the investigation of pathogenesis of certain neurological diseases. Herein, we constructed a novel electrochemical sensor for real-time monitoring of NE released by PC12 cells based on glassy carbon electrode (GCE) modified with honeycomb-like nickel oxide (NiO)-reduced graphene oxide (RGO) nanocomposite. The synthesized NiO, RGO and the NiO-RGO nanocomposite were characterized using X-ray diffraction spectrogram (XRD), Raman spectroscopy and scanning electron microscopy (SEM). The porous three-dimensional honeycomb-like structure of NiO and high charge transfer kinetics of RGO endowed the nanocomposite with excellent electrocatalytic activity, large surface area and good conductivity. The developed sensor exhibited superior sensitivity and specificity towards NE in a wide linear range from 20 nM to 14 μM and 14 μM–80 μM, with a low detection limit of 5 nM. The performances of the sensor in terms of excellent biocompatibility and high sensitivity allow it to be successfully employed in the tracking of NE release from PC12 cells under the stimulation of K+, providing an effective strategy for the real-time monitoring of cellular NE.

Oxygen enriched carbon with hierarchical porous structure derived from biomass waste for high-performance symmetric supercapacitor with decent specific capacity

In this account, elm seeds are employed to prepare oxygen enriched porous carbon materials with three-dimensional honeycomb-like structure (HLPC). The HLPC demonstrates favorable specific capacitance of 501F/g at 1A/g. Moreover, the assembled HLPC//HLPC symmetrical device delivers 18.6Wh/kg at 1310W/kg and maintains 8.36Wh/kg at 13090W/kg, which is regarded as competitive electrode compared with the previously reported biomass carbon-based materials. The outstanding performance is attributed to exceptional oxygen content, which could significantly enhance the overall capacitance and improve the wettability of the electrode. This work holds great potential to realize high-efficient, eco-friendly and industrial-grade production of biomass-derived carbon materials for advanced energy storage applications.

Uniform honeycomb-like microspheres constructed with titanium nitride to confine polysulfides for extremely stable lithium-sulfur batteries

Lithium-sulfur batteries are considered the most promising next-generation electrochemical energy storage devices due to their high theoretical energy density. However, their practical application is hindered by the severe shuttle effect of polysulfides and the low conductivity of sulfur cathode. Herein, we design a titanium nitride host with a three-dimensional honeycomb-like structure via a spray drying method, which has the advantages of metallic conductivity and ultrafast anchoring to realize efficient adsorption and conversion of polysulfide. The honeycomb-like architecture can shorten the diffusion path of lithium ions, and buffer the volume change of sulfur, which can improve reaction kinetics and maintain the stability of the material structure. As a result, the sulfur cathode based on titanium nitride host exhibits an excellent cycling performance with a stable capacity of 650.4 mAh g−1 within 500 cycles at 100 mA g−1. The excellent performance shows the importance of designing cathode materials with reasonable structures in lithium sulfur batteries.

Exceptionally Stable and 20-Connected Lanthanide Metal–Organic Frameworks for Selective CO2 Capture and Conversion at Atmospheric Pressure

Highly thermal and chemically stable, 20-connected lanthanide metal–organic frameworks (MOFs) [{Ln(BTB)(H2O)}·H2O]n (where Ln = Sm (MOF1)/Gd (MOF2), BTB = 1,3,5-tris (4-carboxy phenyl) benzene) have been synthesized solvothermally and characterized by single-crystal X-ray diffraction analysis and other physicochemical methods. MOF1 and 2 are isostructural and feature three-dimensional honeycomb-like structure with large one-dimensional hexagonal channels of dimension ∼10.20 × 10.11 A2. Gas uptake studies of the samples revealed selective adsorption properties of MOF1 for CO2 over other (N2, Ar, and H2) gases. The activated samples of the MOF1/2 act as efficient recyclable catalysts for heterogeneous cycloaddition of CO2 with styrene oxide, resulting in cyclic carbonate with high yield and selectivity. Interestingly, the pore size-dependent catalytic conversion of epoxides has been observed, suggesting the potential utility of MOF1 as a promising heterogeneous catalyst for cycloaddition of carbon dioxide. ...

Creating “hotels” for cells by electrospinning honeycomb-like polymeric structures

It is well established that three-dimensional honeycomb-like nanofibrous structures enhance cell activity. In this work, we report that electrospun polymer nanofibres self-assemble into three-dimensional honeycomb-like structures. The underlying mechanism is studied by varying the polymer solution concentration, collecting substrates and working distance. The polymer solution concentration has a significant effect on the size of the electrospun nanofibres. The collection substrate and working distance affect the electric field strength, the evaporation of solvent and the discharging of nanofibres and consequently these two had a significant influence on the self-assembly of nanofibres.

Bis(2-(1H-imidazol-2-yl)-pyridine)copper(II): Effects of counteranions on the molecular and supramolecular structures

The synthesis and physical properties of bis(2-(1H-imidazol-2-yl)-pyridine)copper(II) with chloride, nitrate and perchlorate as counteranions have been described. Microanalysis, magnetic susceptibility, conductivity and various spectroscopic measurements have been used for the characterization of the complexes. The crystal structures of all three complexes have been determined. Intermolecular hydrogen-bonding interactions and the resulting self-assembly patterns for each of the species have been scrutinized. The chloride containing complex crystallizes as a trihydrate, where the metal ion is in a tetragonally elongated cis-N 4Cl 2 coordination sphere. This complex provides a three-dimensional honeycomb-like structure through N–H⋯Cl, O–H⋯Cl and O–H⋯O hydrogen bonds. In the nitrate containing species, one of the two counteranions coordinates to the metal centre to provide an irregular N 4O 2 coordination sphere, while the other counteranion, with the help of a lattice water molecule, assembles a ladder-like structure via N–H⋯O and bifurcated O–H⋯O,O hydrogen bonds. A one-dimensional polymeric species has been formed when perchlorate is the counteranion. Here one of the two perchlorates acts as a bridge between the metal centres that are in tetragonally elongated trans-N 4O 2 coordination spheres. This polymeric chain, together with the second perchlorate and a water molecule, form a ribbon-like structure due to N–H⋯O and O–H⋯O hydrogen bonds.