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Li‐ion batteries (LIBs) have been widely used in portable electronic devices, the transportation sector, and grid storage. However, LIB anodes are restricted to carbon‐based materials limiting their energy density. Recently, the use of metallic Li as the anode in Li‐metal (LMBs) and solid‐state (LMSSBs) batteries has gained attention due to the high energy densities it can provide. Herein, the research progress in the field to derive a broad picture of the technologies relying on Li metal as the anode is critically assessed. It is essential to understand the Li plating and stripping processes in terms of fundamental electrochemical and physical mechanisms to address the challenges of employing metallic Li. Anode‐free Li‐metal batteries (AFLMBs) and anode‐free solid‐state batteries (AFSSBs) are the most attractive systems discussed in this review. AFLMBs are highly studied, but safety concerns due to Li dendrite growth and side reactions between plated Li metal and liquid electrolyte are some key challenges yet to be resolved. AFSSBs are the ultimate goal in this field, as utilizing a solid‐state electrolyte (SSE) can prevent dendrites at moderate charging rates and realize the potential of the anode‐free battery. However, the general problems with the use of SSEs remain and require substantial research efforts. [ABSTRACT FROM AUTHOR]

We describe the implementation of a system of immobilised enzymes for H2-driven NADH recycling coupled to a selective biotransformation to enable H2-driven biocatalysis in flow. This approach represents a platform that can be optimised for a wide range of hydrogenation steps and is shown here for enantioselective ketone reduction and reductive amination. [ABSTRACT FROM AUTHOR]

Here we present the results of high-resolution x-ray diffraction experiments along with specific heat, resistivity, and magnetization measurements of chemically well-characterized Fe1.12-x MxTe (M = Co, Ni) samples. The motivation is to investigate how the two coupled magnetostructural phase transitions in the antiferromagnetic parent compound Fe1.12Te of chalcogenide superconductors can be tuned. While the two-step magnetostructural transition (tetragonal-to-orthorhombic followed by orthorhombic-to-monoclinic) persists in Fe1.10Co0.02Te, only one, tetragonal-to-orthorhombic transition was observed in Fe1.10Ni0.02Te. Upon increasing the Co and Ni substitution, the structural phase transitions and the long-range magnetic order are systematically suppressed without any sign of superconductivity. For high substitution levels (x > 0.05), a spin-glass-like behavior was observed and the low-temperature structure remains tetragonal. From our results, it can be inferred that the electron doping strongly suppresses the magnetostructural phase transitions. [ABSTRACT FROM AUTHOR]

Heterogeneous biocatalytic hydrogenation is an attractive strategy for clean, enantioselective C[double bond, length as m-dash]X reduction. This approach relies on enzymes powered by H 2 -driven NADH recycling. Commercially available carbon-supported metal (metal/C) catalysts are investigated here for direct H 2 -driven NAD + reduction. Selected metal/C catalysts are then used for H 2 oxidation with electrons transferred via the conductive carbon support material to an adsorbed enzyme for NAD + reduction. These chemo-bio catalysts show improved activity and selectivity for generating bioactive NADH under ambient reaction conditions compared to metal/C catalysts. The metal/C catalysts and carbon support materials (all activated carbon or carbon black) are characterised to probe which properties potentially influence catalyst activity. The optimised chemo-bio catalysts are then used to supply NADH to an alcohol dehydrogenase for enantioselective (>99% ee) ketone reductions, leading to high cofactor turnover numbers and Pd and NAD + reductase activities of 441 h -1 and 2347 h -1 , respectively. This method demonstrates a new way of combining chemo- and biocatalysis on carbon supports, highlighted here for selective hydrogenation reactions., Competing Interests: There are no conflicts to declare., (This journal is © The Royal Society of Chemistry.)

We describe the use of carbon as a versatile support for H 2 -driven redox biocatalysis for NADH-dependent CX bond reductions in batch and flow reactions. In each case, carbon is providing an electronic link between enzymes for H 2 oxidation and reduction of the biological cofactor NAD + , as well as a support for a multi-enzyme biocatalysis system. Carbon nanopowders offer high surface areas for enzyme immobilization and good dispersion in aqueous solution for heterogeneous batch reactions. Difficulties in handling multi-wall carbon nanotubes in aqueous solution are overcome by growing them on quartz tubes to form carbon nanotube column reactors, and we show that these facilitate simple translation of H 2 -driven biocatalysis into flow processes. Using this flow reactor design, high conversions (90%) and total enzyme turnover numbers up to 54,000 could be achieved. Use of an entirely heterogeneous biocatalysis system simplifies recovery and re-use of the enzymes; combined with highly atom-efficient cofactor recycling, this means that high product purity can be achieved. We demonstrate these methods as platform approaches for overcoming challenges with NADH-dependent biocatalysis., (© 2020 Elsevier Inc. All rights reserved.)

LiCoBO 3 could be a promising cathode material given the electronic and ionic conductivity problems are addressed. Here, Mg substitution in LiCoBO 3 is employed to stabilise the structure and improve the electrochemical performance. LiMg 0.1 Co 0.9 BO 3 is synthesised for the first time via sol-gel method and Mg substitution in the structure is verified by X-ray powder diffraction and energy dispersive X-ray analyses. The electrochemical properties are investigated by galvanostatic cycling and cyclic voltammetry tests. The composite electrode with conductive carbon (reduced graphite oxide and carbon black) delivers a first discharge capacity of 32 mA h g -1 within a 4.7-1.7 voltage window at a rate of 10 mA g -1 . The cycling is relatively stable compared to the unsubstituted LiCoBO 3 . Mg substitution may enhance the electrochemical performance of borate-based electrode materials when combined with suitable electrode design techniques., Competing Interests: There are no conflicts to declare., (This journal is © The Royal Society of Chemistry.)

We describe the implementation of a system of immobilised enzymes for H 2 -driven NADH recycling coupled to a selective biotransformation to enable H 2 -driven biocatalysis in flow. This approach represents a platform that can be optimised for a wide range of hydrogenation steps and is shown here for enantioselective ketone reduction and reductive amination.