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Although various hosts have been proposed to accommodate the Lithium (Li) metal to solve the uneven Li deposition and infinite volume change, the pulverization of the host or lithiophilic modification layer easily leads to structural damage and the poor cycling stability of the composite anode. Herein, we design a host of metal nitrides (Mo₂N and WN heterostructures) nanoparticles capsulated in the hollow carbon nanospheres, which can accommodate Li metal to form a stable composite anode. The lithiophilic Mo₂N guides uniform infusion and reduces the nucleation barriers of Li metal during electrochemical process. Note that the rigid WN matrix is uniformly composited with Mo₂N, which can suppress the pulverization of Mo₂N during the repeat Li plating/stripping, ensuring the stability of regulated deposition during long cycling. High mechanical strength, uniform surface potential distribution and good electrolyte wettability of the Li metal-based composite anode guarantee the rapid Li plating/stripping kinetics. Thus, the obtained composite anode can stably cycle 1400 h at 1 mA cm^-2 and 1 mA h cm^-2 in the symmetric battery. The assembled full cells with LiNi_0.8Mn_0.1Co_0.1O₂ (NCM811) also deliver high capacity retention under the high loading (8.6 mg cm^-2) or lean electrolyte (2 μL mg^-1) condition. This work suggests a promising host structure design to construct a highly stable lithium metal anode for practical applications. LESS      Full article

Nanostructured anodic films on transition metals prepared using the electrochemical anodization method have recently attracted particular attention owing to their extraordinary properties and potential use in a variety of applications. Herein, we provide a thorough review of the anodization fabrication of anodic films with different nanostructures, including nanopores, nanotubes, nanoflowers, nanoneedles and nanowires on transition metals, focusing on the growth processes of nanostructured anodic films on three representative transition metals, namely, iron, copper and zinc. Specific consideration is given to the anodization behavior and formed film nanostructures of these transition metals. We conclude that electrolyte composition plays a key role in influencing the final morphologies of anodic films. Fluoride-containing solutions represent universal electrolytes for forming nanostructured anodic films on transition metals. The main applications of the resulting nanostructured anodic films, especially in energy-related fields, such as photoelectrochemical water splitting and supercapacitors, are also presented and discussed. Finally, we indicate the main challenges associated with the fabrication of anodic films with highly ordered nanostructures and the potential future directions of this field are indicated. LESS      Full article

Although Ni-rich layered materials with the general formula LiNi_1-x-yCo_xMn_yO₂ (0 < x, y < 1, NCM) hold great promise as high-energy-density cathodes in commercial lithium-ion batteries, their practical application is greatly hampered by poor cyclability and safety. Herein, a LiNi_0.6Co_0.2Mn_0.2O₂ (NCM622) cathode modified with a surface self-assembling LiLaO₂ coating and subsurface La pillars demonstrates stabilized cycling at 4.6 V. The LiLaO₂-coated NCM622 benefits from the suppression of interfacial side reactions, which relieves the layer-to-rock salt phase transformation and therefore improves the capacity retention under high voltages. Moreover, the La dopant, as a pillar in the NCM622 lattice, plays a dual role in expanding the c lattice parameter to enhance the Li-ion diffusion capability, as well as suppressing Ni antisite defect formation upon cycling. Consequently, the dual-modified NCM622 cathode exhibits an initial Coulombic efficiency of over 85% and a high capacity of over 200 mAh g^-1 at 0.1 C. A specific capacity of 188 mAh g^-1 with a capacity retention of 76% is achieved at 1 C after 200 cycles within a voltage range of 3.0-4.6 V. These findings lay a solid foundation for the materials design and performance optimization of high-energy-density cathodes for Li-ion batteries. LESS      Full article

All-solid-state lithium-sulfur batteries (ASSLSBs) exhibit huge potential applications in electrical energy storage systems due to their unique advantages, such as low costs, safety and high energy density. However, the issues facing solid-state electrolyte (SSE)/electrode interfaces, including lithium dendrite growth, poor interfacial capability and large interfacial resistance, seriously hinder their commercial development. Furthermore, an insufficient fundamental understanding of the interfacial roles during cycling is also a significant challenge for designing and constructing high-performance ASSLSBs. This article provides an in-depth analysis of the origin and issues of SSE/electrode interfaces, summarizes various strategies for resolving these interfacial issues and highlights advanced analytical characterization techniques to effectively investigate the interfacial properties of these systems. Future possible research directions for developing high-performance ASSLSBs are also suggested. Overall, advanced in-situ characterization techniques, intelligent interfacial engineering and a deeper understanding of the interfacial properties will aid the realization of high-performance ASSLSBs. LESS      Full article

Benefiting from the creation of new photovoltaic materials and innovations in device architectures, organic photovoltaic (OPV) cells are booming. Nonetheless, their prosperity is also accompanied by challenges, such as tedious synthetic routes, increasing costs and insufficient operational stability under practical stresses. Polythiophene, with a simple chemical structure, high scalability and excellent charge transport ability, is expected to be the most promising candidate among all kinds of polymer donors. Ternary mixing, as a simple and effective method for improving the efficiency and stability of OPVs, has attracted significant attention in recent decades. This review provides an overview of the recent advances in ternary OPVs based on polythiophene and discusses the role of various third components in three types of OPV active layers, where polythiophene serves as either the host material or additive, and also clarifies how the third component plays a role in determining morphology and device performance, and finally proposes future research directions for ternary OPVs featuring polythiophene. In short, this review provides insights into polythiophene-based multicomponent systems and helps readers better understand the relationships between morphology, efficiency and stability. LESS      Full article

Lithium (Li) metal batteries (LMBs) have emerged as the most prospective candidates for post-Li-ion batteries. However, the practical deployment of LMBs is frustrated by the notorious Li dendrite growth on hostless Li metal anodes. Herein, a protonated Li manganese (Mn) oxide with a high Mn³⁺/Mn⁴⁺ ratio is used as a Li adsorbent for constructing highly stable Li metal anodes. In addition to the Mn³⁺ sites with high Li affinity that afford an ultralow Li nucleation overpotential, the decrease in the average Mnⁿ⁺ oxidation state also induces a disordered adsorbent structure via the Jahn-Teller effect, resulting in improved Li transfer kinetics with a significantly reduced Li electroplating overpotential. Based on the mutually improved Li diffusion and adsorption kinetics, the Li adsorbent is used as a versatile host to enable dendrite-free and stable Li metal anodes in LMBs. Consequently, a modified Li||LiNi_0.8Mn_0.1Co_0.1O₂ (NMC811) coin cell with a high NMC811 loading of 4.3 mAh cm^-2 delivers a high Coulombic efficiency of 99.85% over 200 cycles and the modified Li||NMC811 pouch cell also achieves a remarkable improvement in electrochemical performance. This work demonstrates a novel approach for the preparation of highly efficient Li protection structures for safe LMBs with long lifespans. LESS      Full article