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Silver (Ag) is deemed a promising anode material for capacitive deionization (CDI) due to its high theoretical capacity and efficient selectivity to Cl−. However, the strong volume change during the conversion reaction significantly undermines the cycling performance of the Ag electrode. Additionally, achieving well‐dispersed Ag in the active matrix is challenging, as Ag electrodes prepared by conventional thermal reduction tend to agglomerate. Herein, the organic linker confinement strategy is proposed, applying metal–organic framework (MOF) chemistry between Ag nodes and organic ligands to construct Ag‐based MOF. The uniform dispersion of Ag at the molecular level, confined in the organic matrix, efficiently enhances the utilization of active sites, and strengthens the interfacial stability of Ag. Consequently, the Ag‐MOF for the CDI anode exhibits an excellent Cl− removal capacity of 121.52 mg g−1 at 20 mA g−1 in 500 mg L−1 NaCl solution, and a high Ag utilization rate of 60.54%. After 100 cycles, a capacity retention of 96.93% is achieved. Furthermore, the Cl− capture mechanism of Ag‐MOF is elucidated through density functional theory (DFT) calculations, ex situ XRD, ex situ Raman and XPS. This ingenious electrode design can offer valuable insights for the development of high‐performance conversion electrodes for CDI applications. [ABSTRACT FROM AUTHOR]

Sodium‐ion batteries (SIBs) have been considered as promising replacements to lithium‐ion batteries (LIBs) for large‐scale energy storage applications. For anode materials, titanium dioxide (TiO2) as a typical insertion‐type anode material have been extensively investigated as a safety, stable, cheap and environmental‐friendly anode materials for SIBs. Constructing suitable TiO2 crystal structure is a common modification strategy for improving the diffusion kinetics of sodium ion within TiO2 and its intrinsic electronic conductivity. Herein, a multi‐atomic doped oxygen‐deficient TiO2/C composites (N, S‐NTC) was successfully synthesized with excellent electrochemical performance. Synergistic effect of N, S and Ni elements on the structure, morphology and electrochemical performance was investigated. Electron Paramagnetic Resonance (EPR) spectroscopy, Raman spectroscopy and X‐ray photoelectron spectroscopy (XPS) analysis indicated that the Ni, N, S doping can introduce oxygen deficiency, narrow the bandgap of TiO2 and facilitating Na+ diffusion, further providing higher electronic/ionic conductivities and faster electron transport channel. As a consequence, the anode materials delivered ultrahigh rate performance and cycling performance of a high reversible capacity of 128.6 mA h g−1 at 1 A g−1 after 3000th cycles. [ABSTRACT FROM AUTHOR]

The carbon‐coated LiFe0.5Mn0.5PO4 (C/LFMP) and carbon‐coated LiFe0.5Mn0.5PO4@Li2SiO3 (C/LFMP‐LSO) could be successfully prepared by high temperature solid‐state reaction. Even though the crystal structure and morphology of C/LiFe0.5Mn0.5PO4 was not changed by Li2SiO3 coating, Li2SiO3 modification was able to facilitate the diffusion of lithium ions, resulting in an excellent rate performance and cyclic stability of C/LFMP‐1LSO (1 wt %). The reversible discharge specific capacities of C/LFMP‐1LSO are 157.6 mAh g−1 and 106.3 mAh g−1 at 0.1C and 10C, respectively. Meanwhile, the C/LFMP‐1LSO was cycled for 500 times at 5C with a capacity retention rate of 85.3 %. Furthermore, at a low temperature of 6 °C and 0.2C, the C/LFMP‐1LSO displayed good low temperature performance with a discharge specific capacity of 140.6 mAh g−1. Li2SiO3 coating was considered an effective way to boost the overall electrochemical performance of C/LFMP. [ABSTRACT FROM AUTHOR]