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Technologically important composites with enhanced thermal and mechanical properties rely on the reinforcement by the high specific strength ceramic nanofibers or nanowires (NWs) with high aspect ratios. However, conventional synthesis routes to produce such ceramic NWs have prohibitively high cost. Now, direct transformation of bulk Mg-Li alloys into Mg alkoxide NWs is demonstrated without the use of catalysts, templates, expensive or toxic chemicals, or any external stimuli. This mechanism proceeds through the minimization of strain energy at the boundary of phase transformation front leading to the formation of ultra-long NWs with tunable dimensions. Such alkoxide NWs can be easily converted in air into ceramic MgO NWs with similar dimensions. The impact of the alloy grain size and Li content, synthesis temperature, inductive and steric effects of alkoxide groups on the diameter, length, composition, ductility, and oxidation of the produced NWs is discussed., (© 2020 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.)

Conventional slurry casted electrodes cannot stand high loads or be repeatedly flexed or bent without being fractured, which inhibits their use in flexible batteries. Carbon nanotube (CNT) fabric exhibits a paramount mechanical stability and, due to its porosity, can additionally accommodate an active material within its structure. While solution-based protocols cannot achieve conformal coatings of active materials, chemical vapor deposition (CVD) gives a unique opportunity to control and vary the thickness and homogeneity of the coating. Herein, a conformal CVD coating of amorphous iron (III) phosphate (a-FePO 4 , FP) on flexible CNT fabric and its ability to reversibly accommodate large radius Na ions is reported. The freestanding binder-free CNT@FP electrodes exhibit high-rate capabilities and exceptional cycle stabilities with 98% of retention of initial capacity after 100 cycles. Such electrodes additionally demonstrate high mechanical stability under high loads, remarkable bending characteristics, and modulus of toughness (12 MJ m -3 ) exceeding that of Al. The presented concept of flexible CNT@FePO 4 electrodes with high load-bearing characteristics opens new perspectives toward the formation of light-weight, flexible, multifunctional Na-ion battery electrodes based on abundant materials., (© 2018 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.)