Joined forces: Alcohol dehydrogenase, enoate reductase, and Baeyer–Villiger monooxygenase are combined in a cascade reaction by coexpression in E. coli to have a recombinant whole‐cell biocatalyst. Such an artificial metabolic “mini”‐pathway provides access to functionalized chiral compounds in high yields and optical purities as exemplified for kinetic resolutions, desymmetrizations, and regiodivergent biotransformations.

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A considerable concern in exploring clean, efficient, and renewable energy resources to effectively replace fossil fuels and to combat the environmental problems and energy scarcities for a sustainable future has been observed. In this context, hydrogen is a clean, renewable, energetically efficient fuel with infinite potential for the future, which can generate a large amount of energy through the electrocatalytic splitting of earth‐abundant water resources. Noble metals, owing to their extraordinary efficiency and stability, are state‐of‐the‐art catalysts for the oxygen evolution reaction (OER) process. However, their scarcity and high cost hamper their commercialization. To replace these expensive noble‐metal‐based materials, researchers are extensively working on the development of cost effective, stable, conductive, and efficient non‐noble metal based materials such as transition metal oxides, borides, nitrides, sulfides, phosphides, selenides, perovskites oxides, and layered double hydroxides, where the incorporation of heteroatoms improves the electrocatalytic activity by modifying the electronic structure and enhances the conductivity and stability. In the case of transition‐metal based metal organic frameworks (MOFs) and MOF‐derived materials, the unique structure of MOFs with a high surface area and porosity, as well as rich redox chemistry of transition metals, leads to excellent response towards the OER process. Moreover, direct utilization of carbonaceous materials or making their composites with transition metals not only enhances the conductivity due to their conductive nature but also promotes stability by strongly binding with the electrocatalyst. Owing to the presence of functional groups on the surface or through different interactions, they provide multiple paths for facile electron and ion transport due to the sheet/network like structure, which help in the fine dispersion of electrocatalyst due to high surface area, prevent agglomeration, and in turn results in improved electrocatalytic activity. Besides these advances, a) there is still a need for a thorough understanding of reaction mechanism via in situ spectroscopic techniques to further optimize the composition and design of electrocatalyst to get desired results, b) the stability of the materials should be further enhanced to practically utilize synthesized material under harsh conditions without degradation, and c) the utilization of these optimized OER catalysts in a solar cell to consume solar energy (renewable energy source), remains a key requirement of the modern era.

Bio-nanocomposites-based packaging materials have gained significance due to their prospective application in rising areas of packaged food. This research aims to fabricate biodegradable packaging films based upon polyvinyl alcohol (PVA) and starch integrated with metal-organic frameworks (MOFs) or organic additives. MOFs offer unique features in terms of surface area, mechanical strength, and chemical stability, which make them favourable for supporting materials used in fabricating polymer-based packaging materials. zeolitic imidazolate frameworks (ZIFs) are one of the potential candidates for this application due to their highly conductive network with a large surface area and high porosity. Present research illustrates a model system based on ZIF-67 (C8H10N4Co) bearing 2–10 wt.% loading in a matrix of PVA/starch blend with or without pyrolysis to probe the function of intermolecular interaction in molecular packing, tensile properties, and glass transition process. ZIF-67 nanoparticles were doped in a PVA/starch mixture, and films were fabricated using the solution casting method. It was discovered through scanning electron microscopy (SEM), X-ray diffraction (XRD), thermogravimetric analysis (TGA), and Fourier transform infrared spectroscopy (FTIR) that addition of ZIF-67 and pyrolyzed ZIF-67 changed and enhanced the thermal stability of the membrane. Moreover, 2–10 wt.% loading of ZIF-67 effected the thermal stability, owing to an interlayer aggregation of ZIF-67. The membranes containing pyrolyzed ZIF-67 showed mechanical strength in the order of 25 MPa in a moderate loading of pyrolyzed ZIF-67 (i.e., at 4 wt.%). The crystallinity enhanced by an increment in ZIF-67 loading. On the other hand, pyrolyzed ZIF-67 carbon became amorphous because of the inert environment and elevated temperature. The surface area also increased after the pyrolysis, which helped to increase the strength of the composite films.

This review gives a broad vision of the current progress of transition metals and noble metal based electrocatalysts for ethanol oxidation reaction.