The pursuit of high-abundance, cost-effective sodium-ion batteries represents a longstanding and valuable objective in the field. However, significant challenges remain in the quest for breakthroughs, particularly in the discovery of high-performance anode materials and a deeper understanding of the sodium storage mechanism. In this study, we present novel insights into the sodium storage properties of biomass carbon-reinforced ZnPO (ZnPO/C-c) synthesized via a hydrothermal method followed by annealing, marking the first report of its kind. The unique loose porous structure of the ZnPO/C-c composite offers multiple advantages. It facilitates efficient electrolyte infiltration, enhances the diffusion pathways for sodium ions, expedites electron transfer, and crucially, promotes the retention of ZnPO on the carbon substrate, even under conditions of mechanical stress or pulverization. Consequently, the ZnPO/C-c composite demonstrates significantly improved rate capability, exhibiting specific capacities of 276.11, 234.41, 195.28, and 149.56 mA h g at current densities of 0.2, 0.5, 1, and 2 A g, respectively. Furthermore, it exhibits exceptional cyclic stability with a capacity retention rate of 71% after 1000 charge-discharge cycles at 1 A g. In-depth characterization techniques confirm that the sodium storage mechanism involves a conversion reaction between ZnPO and Zn, as well as an alloying reaction between Zn and ZnNa. Kinetic analysis underscores the predominant role of pseudocapacitance in facilitating sodium storage, particularly at high charge-discharge rates. These findings offer valuable insights and inspiration for the exploration of high-performance ZnPO-based anode materials for sodium-ion batteries, representing a significant step toward the realization of cost-effective and efficient sodium-ion battery technology in the future.

中文翻译：

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生物质碳增强锌基复合氧化物作为优异钠存储的阳极

追求高丰度、具有成本效益的钠离子电池是该领域长期且有价值的目标。然而，在寻求突破方面仍然存在重大挑战，特别是在高性能阳极材料的发现和对钠存储机制的更深入理解方面。在这项研究中，我们对通过水热法然后退火合成的生物质碳增强 ZnPO (ZnPO/Cc) 的钠存储特性提出了新的见解，这是此类报告的第一份。 ZnPO/Cc 复合材料独特的疏松多孔结构具有多种优势。它有助于有效的电解质渗透，增强钠离子的扩散途径，加速电子转移，最重要的是，即使在机械应力或粉碎的条件下，也能促进 ZnPO 在碳基材上的保留。因此，ZnPO/Cc复合材料表现出显着提高的倍率性能，在0.2、0.5、1和2 A g-1的电流密度下分别表现出276.11、234.41、195.28和149.56 mA hg的比容量。此外，它还表现出优异的循环稳定性，1 A g-1 充放电循环 1000 次后容量保持率为 71%。深入的表征技术证实，钠存储机制涉及 ZnPO 和 Zn 之间的转化反应，以及 Zn 和 ZnNa 之间的合金化反应。动力学分析强调了赝电容在促进钠存储方面的主要作用，特别是在高充放电速率下。这些发现为探索高性能ZnPO基钠离子电池负极材料提供了宝贵的见解和启发，代表着未来朝着实现经济高效的钠离子电池技术迈出了重要一步。