An inclusive review and perspective on Cu-based materials for electrochemical water splitting

In recent years, there has been a resurgence of interest in developing green and renewable alternate energy sources as a solution to the energy and environmental problems produced by conventional fossil fuel use. As a very effective energy transporter, hydrogen (H₂) is a possible candidate for the future energy supply. Hydrogen production by water splitting is a promising new energy option. Strong, efficient, and abundant catalysts are required for increasing the efficiency of the water splitting process. Cu-based materials as an electrocatalyst have shown promising results for application in the Hydrogen Evolution Reaction (HER) and Oxygen Evolution Reaction (OER) in water splitting. In this review, our aim is to cover the latest developments in the synthesis, characterisation, and electrochemical behaviour of Cu-based materials as a HER, and OER electrocatalyst, highlighting the impact that these advances have had on the field. It is intended that this review article will serve as a roadmap for developing novel, cost-effective electrocatalysts for electrochemical water splitting based on nanostructured materials with particular emphasis on Cu-based materials for electrocatalytic water splitting.

Tetrazole conjoined organosilane and organosilatrane via the ‘click approach’: a potent Mycobacterium tuberculosis enoyl ACP reductase inhibitor and a dual sensor for Fe(iii) and Cu(ii) ions

This article includes the synthesis and characterization of tetrazole-allied organosilane and organosilatrane. The tetrazole-allied silatrane was explored for molecular docking and optical aspects.

A {Ni12}-Wheel-Based Metal-Organic Framework for Coordinative Binding of Sulphur Dioxide and Nitrogen Dioxide

Air pollutions by SO 2 and NO 2 have caused significant risks on the environment and human health. Understanding the mechanism of active sites within capture materials is of fundamental importance to the development of new clean-up technologies. Here we report the crystallographic observation of reversible coordinative binding of SO 2 and NO 2 on open Ni(II) sites in a metal-organic framework (NKU-100) incorporating an unprecedented {Ni 12 }-wheel, which exhibits six open Ni(II) sites on desolvation. Immobilised gas molecules are further stabilised by cooperative host-guest interactions comprised of hydrogen bonds, π ··· π interactions and dipole interactions. At 298 K and 1.0 bar, NKU-100 shows adsorption uptakes of 6.21 and 5.80 mmol g -1 for SO 2 and NO 2 , respectively. Dynamic breakthrough experiments have confirmed the selective retention of SO 2 and NO 2 at low concentrations under dry conditions. This work will inspire the future design of efficient sorbents for the capture of SO 2 and NO 2 .

Nitrogen-Based Linkers with a Mesitylene Core: Synthesis and Characterization

Mesitylene was used as a core in seven new tritopic nitrogen containing linkers. Three of the linkers, each containing three nitrile groups, were obtained through Suzuki, Sonogashira and Heck-type coupling reactions. Next, these were converted to tetrazol-5-yl moieties by the cycloaddition of sodium azide to the nitrile functionalities. The last linker, containing three 1,2,3-triazol-4-yl moieties, was synthesized by the Huisgen cycloaddition of phenyl azide to the corresponding alkyne. The latter was obtained via a Corey–Fuchs reaction sequence from the previously reported formyl derivative. As the proof of concept for their potential in MOF design, one of the nitriles was used to build an Ag-based network.

Zinc(ii) and cadmium(ii) amorphous metal-organic frameworks (aMOFs): study of activation process and high-pressure adsorption of greenhouse gases

Two novel amorphous metal-organic frameworks (aMOFs) with chemical composition {[Zn₂(MTA)]·4H₂O·3DMF} _n (UPJS-13) and {[Cd₂(MTA)]·5H₂O·4DMF} _n (UPJS-14) built from Zn(ii) and Cd(ii) ions and extended tetrahedral tetraazo-tetracarboxylic acid (H₄MTA) as a linker were prepared and characterised. Nitrogen adsorption measurements were performed on as-synthesized (AS), ethanol exchanged (EX) and freeze-dried (FD) materials at different activation temperatures of 60, 80, 100, 120, 150 and 200 °C to obtain the best textural properties. The largest surface areas of 830 m² g^-1 for UPJS-13 (FD) and 1057 m² g^-1 for UPJS-14 (FD) were calculated from the nitrogen adsorption isotherms for freeze-dried materials activated at mild activation temperature (80 °C). Subsequently, the prepared compounds were tested as adsorbents of greenhouse gases, carbon dioxide and methane, measured at high pressures. The maximal adsorption capacities were 30.01 wt% CO₂ and 4.84 wt% CH₄ for UPJS-13 (FD) and 24.56 wt% CO₂ and 6.38 wt% CH₄ for UPJS-14 (FD) at 20 bar and 30 °C.

Three Mn(ii) metal–organic frameworks with the same chemical composition, but different topological structures and properties

Solvothermal reactions of a novel multidentate ligand, 2,5-bis-(1,2,4-triazol-1-yl)-terephthalic acid (H₂TTPA), with MnCl₂ afforded three structurally distinct coordination polymers with the same formula, [Mn(TTPA)·H₂O]_n (Mn-(1–3)).

Cu2O nanoparticle-catalyzed synthesis of diaryl tetrazolones and investigation of their solid-state properties

1,4-Diaryl tetrazolones 1 have been synthesized by Cu₂O nanoparticle-catalyzed C–N coupling of aryl tetrazolones 2 with aryl boronic acids 3 in the presence of oxygen, and their crystal structures have been reported.

Solvent-controlled metal coordination polymers of Co(ii) with different topological structures and properties

Three multidimensional Co-polymers were obtained. Co-1 exhibits as a 2D layer. Co-2 displays as a tetranodal (4,4,5,6)-connected 3D MOFs. Co-3 is a binodal (4,6)-connected 3D framework.