Tweaking the electrochemical activity of maricite NaMnPO4 in sodium batteries using different manganese precursors via polyol method

Recent advances and promise of MXene-based composites as electrode materials for sodium-ion and potassium-ion batteries

With the increasing demand for sustainable energy and concerns about the scarcity of lithium resources, sodium and potassium ion batteries have emerged as promising alternative energy storage technologies. MXene, as a novel two-dimensional material, possesses exceptional electrical conductivity, high surface area, and tunable structural features that make it an ideal candidate for high-performance electrode materials. However, its limited theoretical capacity hinders its widespread application. To overcome this limitation, MXene has been combined with other materials through synergistic effects between different components to enhance the overall electrochemical performance and expand its application in sodium/potassium ion batteries. Recently, substantial advancements have been realized in the exploration of MXene-based composites as energy storage materials, encompassing their synthesis, design, and the comprehension of charge storage mechanisms. This paper aims to propose a comprehensive summary of the latest developments in MXene-based composites as electrode materials for sodium ion batteries and potassium ion batteries, with a particular emphasis on the enhanced physicochemical properties resulting from composite formation. Moreover, the challenges faced by MXene materials in sodium ion batteries and potassium ion batteries are thoroughly discussed, and future research directions to further advance this field are proposed.

Recent Advances in Sodium-Ion Batteries: Cathode Materials

Emerging energy storage systems have received significant attention along with the development of renewable energy, thereby creating a green energy platform for humans. Lithium-ion batteries (LIBs) are commonly used, such as in smartphones, tablets, earphones, and electric vehicles. However, lithium has certain limitations including safety, cost-effectiveness, and environmental issues. Sodium is believed to be an ideal replacement for lithium owing to its infinite abundance, safety, low cost, environmental friendliness, and energy storage behavior similar to that of lithium. Inhered in the achievement in the development of LIBs, sodium-ion batteries (SIBs) have rapidly evolved to be commercialized. Among the cathode, anode, and electrolyte, the cathode remains a significant challenge for achieving a stable, high-rate, and high-capacity device. In this review, recent advances in the development and optimization of cathode materials, including inorganic, organometallic, and organic materials, are discussed for SIBs. In addition, the challenges and strategies for enhancing the stability and performance of SIBs are highlighted.

New Phosphate Zn2Fe(PO4)2 Cathode Material for Nonaqueous Zinc Ion Batteries with Long Life Span

Phosphate-based cathode materials attract much more attention and are widely used as energy storage materials based on their high economic efficiency and eco-friendly property, their stable potential plateau, and their high thermodynamic stability. A new phosphate family member, Zn₂Fe(PO₄)₂ (ZFP), was successfully explored and synthesized by the scalable high-temperature annealing method, followed by coating a thin carbon layer to optimize the electrotonic conductivity. This obtained ZFP featuring with a tunnel structure can be utilized as a cathode material for Zn²⁺ ion extraction and insertion, in which Zn²⁺ ion diffusion behaviors primarily contribute the specific capacity. Based on the actual reversible capacity of ZFP@C of 73 mA h g^-1, the application for zinc ion batteries (ZIBs) has potential due to its long life span. The electrochemical performance is primarily contributed from the high Zn²⁺ ion diffusion rate and low apparent activation energy. This new explored ZFP can accelerate the development of realizing ZIBs with long life span.

Yeast Template-Derived Multielectron Reaction NASICON Structure Na3MnTi(PO4)3 for High-Performance Sodium-Ion Batteries

The sodium super ion conductor (NASICON) structure materials are essential for sodium-ion batteries (SIBs) due to their robust crystal structure, excellent ionic conductivity, and flexibility to regulate element and valence. However, the poor electronic conductivity and inferior energy density caused by the nature of these materials have always been obstacles to commercialization. Herein, using yeast as a template to derive NASICON structure Na₃MnTi(PO₄)₃ (NMTP) materials (noted as Yeast@NMTP/C) is presented. The Yeast@NMTP/C material retains the microsphere morphology of the yeast template and not only controls the particle size (around 2 μm) to shorten the Na⁺ diffusion pathways but also improves the electronic conductivity to optimize the electrochemical kinetics. The Yeast@NMTP/C cathode delivers reversible multielectron redox reactions including Ti^4+/3+, Mn^3+/2+, and Mn^4+/3+ and exhibits a high capacity of 108.5 mAh g^-1 with a 79.2% capacity retention after 1000 cycles at a 2C rate. The sodium storage mechanism of Yeast@NMTP/C reveals that the addition of Ti^4+/3+ redox plays a key role in improving the Na⁺ diffusion kinetics, and both solid-solution and two-phase reactions take place during the desodiation and sodiation process. Additionally, the high-rate and long-span cycle performance of Yeast@NMTP/C at 10C is ascribed to contribute to pseudocapacitance.