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Organic semiconductor materials composed of π⁻π stacking aromatic compounds have been under intense investigation for their potential uses in flexible electronics and other advanced technologies. Herein we report a new family of seven π⁻π stacking compounds of silver(I) bis-N-(4-pyridyl) benzamide with varying counterions, namely [Ag(NPBA)2]X, where NPBA is N-(4-pyridyl) benzamine, X = NO₃- (1), ClO₄- (2), CF₃SO₃- (3), PF₆- (4), BF₄- (5), CH₃PhSO₃- (6), and PhSO₃- (7), which form extended π-π stacking networks in one-dimensional (1D), 2D and 3D directions in the crystalline solid-state via the phenyl moiety, with average inter-ring distances of 3.823 Å. Interestingly, the counterions that contain π⁻π stacking-capable groups, such as in 6 and 7, can induce the formation of mesomorphic phases at 130 °C in dimethylformamide (DMF), and can generate highly branched networks at the mesoscale. Atomic force microscopy studies showed that 2D interconnected fibers form right after nucleation, and they extend from ~30 nm in diameter grow to reach the micron scale, which suggests that it may be possible to stop the process in order to obtain nanofibers. Differential scanning calorimetry studies showed no remarkable thermal behavior in the complexes in the solid state, which suggests that the mesomorphic phases originate from the mechanisms that occur in the DMF solution at high temperatures. An all-electron level simulation of the band gaps using NRLMOL (Naval Research Laboratory Molecular Research Library) on the crystals gave 3.25 eV for (1), 3.68 eV for (2), 1.48 eV for (3), 5.08 eV for (4), 1.53 eV for (5), and 3.55 eV for (6). Mesomorphic behavior in materials containing π⁻π stacking aromatic interactions that also exhibit low-band gap properties may pave the way to a new generation of highly branched organic semiconductors.

Herein we present a modified iodine clock experiment which replaces starch with cellulose paper. This provides the reaction with a white solid surface in which color change can be clearly observed and reduces reagent amounts required to 540 µL per group. After data acquisition, students are required to calculate reaction orders and the reaction constant k, culminating in their ability to discern the rate equation for this reaction. This experiment is ideal for teaching kinetics in high school and undergraduate settings, particularly if liquid waste disposal is not readily available or if high importance is placed upon minimizing their environmental impact.

Zinc oxide nanoparticles (ZnO NPs) with a high photocatalytic performance were prepared by using the aerobic combustion of saccharides such as glucose, fructose, dextrin, and starch with zinc nitrate. The ZnO NPs were characterized by using transmission electron microscopy (TEM), scanning electron microscopy (SEM), energy-dispersive X-ray scattering spectroscopy (EDX), X-ray powder diffraction (XRPD), and UV-vis spectroscopy. The TEM images revealed that the ZnO NPs have sizes ranging from ~20 to 35 nm with a bandgap of ~3.32 eV. The XRPD pattern revealed the hexagonal wurtzite crystalline structure of the ZnO NPs. The photocatalytic properties of the ZnO NPs were studied by the photocatalytic degradation of methyl orange (MO) in deionized water (DIW) and simulated fresh drinking water (FDW) under ultraviolet light (UV-B) and sunlight illumination. The terephthalic acid photoluminescence technique was also used to study the generation of a hydroxyl radical (•OH) by ZnO NPs. The saccharide-derived ZnO NPs exhibited higher photocatalytic activity than the nonsaccharide-derived ZnO NPs. Varying the type of saccharides used during the calcination had some effect on the degree of the catalytic enhancement. [ABSTRACT FROM AUTHOR]

The syntheses, structures and N2 adsorption properties of six new supramolecular metallacycles are reported. The metallacycles stack to form porous structures in the crystalline state and a guest exchange study with nitromethane and toluene reveals that the nanopore in [(dppp)-Pt]2(OTf)4 is a flexible property which was transferred from the linker to the supramolecular structure in the solid state.

The supramolecular chemistry of several metal complexes of N-(4-pyridyl)benzamide (NPBA) with the general formula [M(sub a)(NPBA)(sub 2)A(sub b)S(sub C)] are described. The effects of multidimensional noncovalent networks on magnetic moments is discussed in the range between 2 and 300 K of 1-D, 2-D and 3-D paramagnetic networks.

Research has been conducted on the CO(III) complexes of two designed ligands. Results indicate that they are the first complexes with carboxamido nitrogens and thiolato sulfurs as donors.

Low dimensional electrocatalytic heterostructures have recently attracted significant attention in the catalysis community due to their highly tuneable interfaces and exciting electronic features, opening up new possibilities for effective nanometric control of both the charge carriers and energetic states of several intermediate catalytic species. In-depth understanding of electrocatalytic routes at the interface between two or more low-dimensional nanostructures has triggered the development of heterostructure nanocatalysts with extraordinary properties for water splitting reactions, NRR and CO2RR. This tutorial review provides an overview of the most recent advances in synthetic strategies for 0D–1D, 0D–2D, and 2D–2D nanoheterostructures, discussing key aspects of their electrocatalytic performances from experimental and computational perspectives as well as their applications towards the development of overall water splitting and Zn–air battery devices. [ABSTRACT FROM AUTHOR]

Lithium ion battery (LIB) is a key solution to the demand of ever-improving, high energy density, clean-alternative energy systems. In LIB, graphite is the most commonly used anode material; however, lithium-ion intercalation in graphite is limited, hindering the battery charge rate and capacity. To date, one of the approaches in LIB performance improvement is by using porous carbon (PC) to replace graphite as anode material. PC's pore structure facilitates ion transport and has been proven to be an excellent anode material candidate in high power density LIBs. In addition, to overcome the limited lithium-ion intercalation obstacle, nanostructured anode assembly has been extensively studied to increase the lithium-ion diffusion rate. Among these approaches, high specific surface area metal oxide nanowires connecting nanostructured carbon materials accumulation have shown promising results for enhanced lithium-ion intercalation. Herein, we demonstrate a hydrothermal approach of growing TiO2 nanowires (TON) on microwave exfoliated graphene oxide (MEGO) to further improve LIB performance over PC. This MEGO-TON hybrid not only uses the high surface area of MEGO but also increases the specific surface area for electrode–electrolyte interaction. Therefore, this new nanowire/MEGO hybrid anode material enhances both the specific capacity and charge–discharge rate. Scanning electron microscopy and X-ray diffraction were used for materials characterization. Battery analyzer was used for measuring the electrical performance of the battery. The testing results have shown that MEGO-TON hybrid provides up to 80% increment of specific capacity compared to PC anode. [ABSTRACT FROM AUTHOR]

Correction for 'Spent tea leaves templated synthesis of highly active and durable cobalt-based trifunctional versatile electrocatalysts for hydrogen and oxygen evolution and oxygen reduction reactions' by Md Ariful Ahsan et al., Green Chem., 2020, 22, 6967–6980, https://doi.org/10.1039/D0GC02155E. [ABSTRACT FROM AUTHOR]

The facile synthesis, crystal structure, and magnetic properties of a hydroxo-bridged copper(II) cubane complex are reported. It is concluded that the single multistep reaction yields a new copper cubane complex with outer-sphere H-bonding that cause significant variations in the stability ad solid-state bonding parameters of the metal cluster.

Nature-inspired hierarchical architectures have recently drawn enormous interest in the materials science community, being considered as promising materials for the development of high-performance wearable electronic devices. Their highly dynamic interfacial interactions have opened new horizons towards the fabrication of sustainable sensing and energy storage materials with multifunctional properties. Nature-inspired assemblies can exhibit impressive properties including ultrahigh sensitivity, excellent energy density and coulombic efficiency behaviors as well as ultralong cycling stability and durability, which can be finely tuned and enhanced by controlling synergistic interfacial interactions between their individual components. This tutorial review article aims to address recent breakthroughs in the development of advanced Nature-inspired sensing and energy storage materials, with special emphasis on the influence of interfacial interactions over their improved properties. [ABSTRACT FROM AUTHOR]

The rational design of high-performance trifunctional catalysts for oxygen reduction and oxygen and hydrogen evolution reactions is of vital importance for the implementation of green energy conversion technologies. Herein, trifunctional electrocatalysts comprising cobalt nanoparticles uniformly embedded in porous carbon networks were fabricated using a spent tea leaves (STL) template via a one-step carbothermal-reduction strategy at different temperatures. STL played a synthetic dual role in constructing nanocatalysts by acting as efficient scavengers to trap cobalt cations via electrostatic interactions and as carbon sources to generate a porous carbon matrix. Full characterization of the as-synthesized materials revealed the crucial effect of temperature on the crystallinity, surface area, number of surface defects and interfacial charge distribution properties. Furthermore, the trifunctional catalytic activity of the nanoparticles can be finely tuned by varying the carbonization temperature. Co@PC-7 displayed a superior trifunctional catalytic activity exhibiting an excellent performance for hydrogen production with an overpotential of 153 mV (vs. RHE) to achieve 10 mA cm−2, and an impressive bifunctional oxygen electrocatalytic activity with an ultralow potential difference between OER and ORR (ΔE = η10 − E1/2) of 0.69 V, which is one of the lowest values reported in the literature for transition metal nanocatalysts. The remarkable performance of Co@PC-7 is mainly ascribed to its unique structural properties, which give rise to highly desirable charge distributions at the metal/carbon electrochemical interfaces to perform efficient trifunctional water splitting electrocatalysis. [ABSTRACT FROM AUTHOR]

Research has been conducted on cobalt(III) complexes containing nitrile hydratase. The authors have synthesized these complexes in the effort to investigate the role of Cys-S oxidation in Co-containing nitrile hydratase.

We have reported sucrose-mediated facile route for the preparation of high surface area cobalt (Co), nickel (Ni), and copper (Cu) sponges. Scanning electron microscopy (SEM) and transmission electron microscopy (TEM) revealed the sponge-like and nanoparticle-like morphologies of the metal sponges. The catalytic activity of the metal sponges was studied via the reduction of organic pollutants, including 4-nitrophenol (4-NP), methyl orange (MO) and methylene blue (MB) in water. It was found that the Cu sponge exhibited the fastest rate for the reduction of 4-NP, MO, and MB, followed by the Co and Ni sponges, respectively. The metal sponges exhibited excellent catalytic stability for the reduction of 4-NP for multiple cycles. In addition, due to their magnetic properties, the Co and Ni sponges could be easily recovered and reused by applying an external magnetic field. [ABSTRACT FROM AUTHOR]