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Intermediate temperature solid oxide fuel cell (SOFC) operation provides numerous advantages such as high combined heat and power (CHP) efficiency, potentially long-term material stability, and the use of low-cost materials. However, due to the sluggish kinetics of the oxygen reduction reaction at intermediate temperatures (500–700 °C), the cathode of SOFC requires an efficient and stable catalyst. Significant progress in the development of cathode materials has been made over recent years. In this article, multiple strategies for improving the performance of cathode materials have been extensively reviewed such as A- and B-site doping of perovskites, infiltration of catalytic active materials, the use of core-shell composites, etc. Emphasis has been given to intrinsic properties such as chemical and thermal stability and oxygen transport number. Furthermore, to avoid any insulating phase formation at the cathode/electrolyte interface, strategies for interfacial layer modifications have also been extensively reviewed and summarized. Based on major technical challenges, future research directions have been proposed for efficient and stable intermediate temperature solid oxide fuel cell (SOFC) operation. [ABSTRACT FROM AUTHOR]

The emergence of liquid metal catalysts endows electrocatalytic processes with enhanced efficiencies by eliminating coking issues that rapidly deactivate conventional solid catalysts. Alloying them with trace amounts of redox-active metal additives can further improve their catalytic activity. Here we report a vanadium-liquid metal alloy with superior activity that can drive electrochemical reduction of CO2 into solid carbon. The reaction mechanism has been thoroughly investigated and discussed. In addition, artificial neural networks trained by machine learning have been demonstrated to be powerful in predicting performance of LM alloys with various compositions. [ABSTRACT FROM AUTHOR]

Because of their large specific surface area, high porosity, changeable pore size, and ordered pore arrangement, metal–organic frameworks (MOFs) are emerging as electrocatalysts in various fields of energy resources and bio-sensors. In this work, we report a one-pot synthesis of trimetallic MOFs (Co–Ni–Al-MOFs), as well as bimetallic MOFs (Co–Ni-MOFs, Co–Al-MOFs, and Ni–Al-MOFs) using Co, Ni, and Al metal salts and BTC and 4,4′-bipyridine as linkers, their characterization for surface morphology, functional group and elemental analysis using various analytical techniques and explored them as tri-modal catalysts for thiophene electrooxidation, water splitting and chemical reduction of 4-nitrophenol (4-NP). Electrochemical studies using linear sweep voltammetry (LSV) and electrochemical impedance spectroscopy (EIS) on Co–Ni–Al-MOFs showed the lowest onset potential of 1.36 V with a lower Tafel slope of 181 mV dec−1 and charge transfer resistance value (Rct) of 447 Ω for the effective electrooxidation of thiophene. Further catalytic activity studies towards water splitting revealed that Co–Ni–Al-MOFs displayed superior catalytic activity towards the HER and the OER at lower overpotentials of 174 and 220 mV with Tafel slopes of 108 and 97 mV dec−1 respectively, compared to other bimetallic MOFs with excellent long-term stability, as revealed by chronoamperometry (CA). The high catalytic activity of Co–Ni–Al-MOFs may be associated with their larger surface area and higher pore volume than those of the other bi-metallic MOFs, as studied by BET analysis, leading to innumerable redox-active sites towards electrochemical processes. Moreover, the catalytic activity of the as prepared catalysts was assessed towards the reduction of 4-NP to 4-aminophenol (4-AP), where Co–Ni–Al-MOFs exhibited exceptional activity with a minimum reduction time of 8 min bearing a high rate constant value. [ABSTRACT FROM AUTHOR]

Scientists are often inspired by nature, where naturally occurring morphologies, such as those that resemble animals and plants, can be created in the lab. In this review, we have provided an overview on complex superstructures of animals, plants and some similar shapes from the natural world. We begin this review with a discussion about the formation of various animal‐like shapes from small organic molecules and polymers, and then move onto plants and other selected shapes. Literature surveys reveal that most of the polymers studied tend to form micellar structures, with some exceptions. Nevertheless, small organic molecules tend to form not only micellar structures but also other animal shapes such as worms and caterpillars. These superstructures tend to have high surface areas and variable surface morphology, making them very useful material for applications in various field such as catalysis, solar cells, and biomedicine, amongst others. [ABSTRACT FROM AUTHOR]

A series of complex salts is described in which electron-rich [{[Fe.sup.II][(CN).sub.5]}.sup.3-] centers are coordinated to pyridyl ligands with electron-accepting N-methyl/aryl-pyridinium substituents. The hyper-Rayleigh scattering (HRS) data in methanol has shown that the stronger solvatochromism of the [Fe.sup.II] complexes causes their nonlinear optical (NLO) responses to surpass those of their [Ru.sup.II] counterparts upon changing the solvent medium.

Research has been conducted on the macrocyclic cobalt hexaamines. The ability of these hexaamines to reduce the overpotential for hydrogen evolution in aqueous solution is examined.

A novel method for the synthesis of a new macrocyclic hexaamine L6 and its hexadentate-coordinated CoIII complex was developed based on the reduction of the [CuL5]2+ complex. Analysis of the self-exchange electron transfer properties of the [CoL6]Cl2(ClO4) complex via X-ray crystallography indicated the presence of short Co-N bond lengths and a high-energy d-d electronic maxima. Furthermore, the CoIII/II self-exchange electron transfer rate constants of the complex exhibited marked variations in the disposition of its primary amino groups.