In this work, the effect of varying the size of the precursor raw materials SiO₂ and ZrO₂ in the solid-state synthesis of NASICON in the form Na₃Zr₂Si₂PO₁₂ was studied. Nanoscale and macro-scale precursor materials were selected for comparison purposes, and a range of sintering times were examined (10, 24 and 40 h) at a temperature of 1230 °C. Na₃Zr₂Si₂PO₁₂ pellets produced from nanopowder precursors were found to produce substantially higher ionic conductivities, with improved morphology and higher density than those produced from larger micron-scaled precursors. The nanoparticle precursors were shown to give a maximum ionic conductivity of 1.16 × 10⁻³ S cm⁻¹ when sintered at 1230 °C for 40 h, in the higher range of published solid-state Na₃Zr₂Si₂PO₁₂ conductivities. The macro-precursors gave lower ionic conductivity of 0.62 × 10⁻³ S cm⁻¹ under the same processing conditions. Most current authors do not quote or consider the precursor particle size for solid-state synthesis of Na₃Zr₂Si₂PO₁₂. This study shows the importance of precursor powder particle size in the microstructure and performance of Na₃Zr₂Si₂PO₁₂ during solid-state synthesis and offers a route to improved predictability and consistency of the manufacturing process.

Rapid uptake of lithium‐centric technology, e.g., electric vehicles and large‐scale energy storage, is increasing the demand for efficient technologies for lithium extraction from aqueous sources. Among various lithium‐extraction technologies, membrane processes hold great promise due to energy efficiency and flexible operation in a continuous process with potential commercial viability. However, membrane separators face challenges such as the extraction efficiency due to the limited selectivity toward lithium relative to other species. Low selectivity can be ascribed to the uncontrollable selective channels and inefficient exclusion functions. However, recent selectivity enhancements for other membrane applications, such as in gas separation and energy storage, suggest that this may also be possible for lithium extraction. This review article focuses on the innovations in the membrane chemistries based on rational design following separation principles and unveiling the theories behind enhanced selectivity. Furthermore, recent progress in membrane‐based lithium extraction technologies is summarized with the emphasis on inorganic, organic, and composite materials. The challenges and opportunities for developing the next generation of selective membranes for lithium recovery are also pointed out.

As worldwide energy consumption continues to increase, so too does the demand for improved energy storage technologies. Supercapacitors are energy storage devices that are receiving considerable interest due to their appealing features such as high power densities and much longer cycle lives than batteries. As such, supercapacitors fill the gaps between conventional capacitors and batteries, which are characterised by high power density and high energy density, respectively. Carbon nanomaterials, such as graphene nanoplatelets, are being widely explored as supercapacitor electrode materials due to their high surface area, low toxicity, and ability to tune properties for the desired application. In this review, we first briefly introduce the theoretical background and basic working principles of supercapacitors and then discuss the effects of electrode material selection and structure of carbon nanomaterials on the performances of supercapacitors. Finally, we highlight the recent advances of graphene nanoplatelets and how chemical functionalisation can affect and improve their supercapacitor performance.

A 12.5 at% replacement of Sb with Bi in Sb ₂ Te ₃ leads to a Na-ion battery anode material with enhanced resistance to mechanical degradation when used as micron-sized powder and not as a nanostructured carbon composite.