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The pursuit of high energy densities propels the design of next‐generation nickel‐based layered oxide cathodes. The utilization of low‐cobalt, ultrahigh‐nickel layered oxide cathodes, and the extension of operating voltages promise enhanced energy density. However, stability and safety face challenges associated with nickel content, including structural degradation, lattice oxygen evolution, and thermal instability. In this study, a promising strategy of Al and Nb dual‐bulk‐doping is presented in high‐Ni cathode materials of LiNi0.96Co0.04O2 (NC) to stabilize the bulk structure, suppress oxygen release, and attain superior electrochemical performance at high voltages. The introduction of Al and Nb effectively raises the migration energy of Ni2+ into Li sites and stabilizes lattice oxygen through strengthened Al─O and Nb─O bonds. Furthermore, the substitution of high‐valence Nb ions reduces the charge depletion of lattice oxygen and induces an ordered microstructure. The Al and Nb dual‐bulk‐doping strategy mitigates strain and stress associated with the H2↔H3 phase transition, reducing the generation and propagation of microcracks. The resulting Li(Ni0.96Co0.04)0.985Al0.01Nb0.005O2 (NCAN) cathode exhibits superior cycling stability, with a capacity retention of 77.8% after 300 cycles, even when operating at a high‐voltage of 4.4 V, outperforming the NC (48.5%). This work provides a promising perspective for developing high‐voltage and high‐Ni cathode materials. [ABSTRACT FROM AUTHOR]

To study the intervention effect of narrative therapy on non-suicidal self-injury (NSSI), as well as anxiety and depression symptoms in adolescents with depressive disorder. Methods Sixty adolescents with depressive disorder and NSSI were randomly assigned to either the intervention group or the control group using coin flipping. The control group received conventional psychological support, while the intervention group received individual narrative therapy in addition to the conventional psychological support (twice a week, 60 minutes per session, for a total of 3 weeks). Assessment of treatment efficacy was conducted using the Adolescent Self-Harm Questionnaire, Children's Depression Inventory, and Children's Anxiety and Mood Scale before the intervention, at the end of the intervention, and one month after the intervention for both groups. Results A total of 26 adolescents in the intervention group and 29 adolescents in the control group completed the entire study. At the end of the intervention and one month after the intervention, the intervention group showed a significant reduction in the NSSI frequency score, NSSI level, anxiety score, and depression score compared to before the intervention (P<0.017). Moreover, at the end of the intervention and one month after the intervention, the intervention group exhibited significantly lower NSSI frequency score, NSSI severity score, NSSI level, anxiety score and depression score compared to the control group (P<0.05). Conclusions Narrative therapy is effective in reducing NSSI frequency and alleviating NSSI severity, as well as anxiety and depression symptoms in adolescents with depressive disorder. [ABSTRACT FROM AUTHOR]

Lithium–sulfur batteries with high energy density are considered to be one of the most promising candidates for the next‐generation energy storage devices. Electrolyte as the medium for Li+ transportation between the electrodes, also plays a crucial role in inhibiting the dissolution and diffusion of lithium polysulfides in Li–S batteries. The working mechanism of Li–S batteries in different electrolytes is classified into "solid‐liquid‐solid" and "solid‐solid" conversions. Under the "solid‐liquid‐solid" conversion, Li–S batteries would inevitably face the challenges such as "shuttle effect" that lead to poor cycle performance, and under the "solid‐solid" conversion, they would face interface mismatch that limits the utilization of sulfur with low energy density, while both conversion mechanisms cause uncontrollable Li dendrites on anode. According to the conversion mechanism, electrolytes can be divided into ether‐based, ionic liquid‐based, gel polymer electrolytes, and polymer‐based solid‐state electrolytes with "solid‐liquid‐solid" conversion, as well as carbonate‐based electrolytes and oxide/sulfide‐based solid‐state electrolytes with "solid‐solid" conversion. Based on the conversion mechanism of active materials in different electrolytes, the current status on the strategies from multiple perspectives are summarized to improve the electrochemical performance, with the hope to provide a comprehensive guideline toward the development of suitable electrolytes for Li–S batteries. [ABSTRACT FROM AUTHOR]

Cobalt‐free ultrahigh‐nickel layered oxide cathodes hold great promise for reducing the cost and enhancing the energy density of Li‐ion batteries. However, the increasing Ni content and the elimination of Co could cause severe interfacial and structural degradation, leading to poor electrochemical performance of ultrahigh‐nickel layered oxide cathodes. Here, a Co‐free oxide, LiNi0.96Al0.03Ca0.01O2 (NAC), where Ca acts as pillar ions at the surface and Al works as an oxygen stabilizer across the bulk, is presented. An epitaxial layer rich in segregated Ca can effectively inhibit adverse surface reconstruction at high states of charge, together with the oxygen stabilization of bulk phase by doping Al, significantly reinforcing the structural rigidity of the layered oxide during cycling. The fabricated NAC cathode material exhibits exceptional electrochemical performance in terms of high cycling stability with 93% capacity retention over 500 cycles and a material‐level energy density of ~800 Wh kg−1. This study provides an efficient and feasible strategy to design and stabilize ultrahigh‐nickel oxides for lithium‐ion batteries. [ABSTRACT FROM AUTHOR]

High‐Ni layered oxide cathodes hold a great promise for fabricating high‐energy lithium‐ion batteries. However, the oxygen evolution during cycling is a crucial factor in the structure deterioration, potential change, and capacity decay of cathodes, limiting the commercial application of high‐Ni (Ni > 0.9) layered oxides in batteries. Herein, we demonstrate a feasible approach to enhance the stability of oxygen framework, through the surface oxygen immobilization with yttrium and bulk oxygen stabilization with aluminum in high‐Ni layered oxides. As expected, benefiting from the oxygen‐stabilized framework, the bulk structure deterioration, and interfacial parasitic reaction are mitigated obviously during battery operation, along with the improved thermal stability of cathode. Correspondingly, the as‐prepared high‐Ni oxide delivers high reversible capacity, impressive cycle ability, and low potential polarization upon cycling. Such significant improvement on the electrochemical performance is primarily attributed to the strong oxygen affinities of both yttrium at the surface layer and aluminum in the bulk, which synergistically stabilizes the oxygen framework of high‐Ni oxide via raising the energy barrier for oxygen evolution. Therefore, building the stable oxygen framework is critical for enhancing the energy density output, cycle operation, and thermal stability of high‐Ni oxide cathodes. [ABSTRACT FROM AUTHOR]

The rationale for ambient degradation behaviors in hole transport layer (HTL)‐free carbon‐based perovskite solar cells (PSCs) still remains a mystery, although carbon‐based PSCs have been the frontrunner among the emerging next‐generation photovoltaics owing to their low cost of materials and fabrication process, as well as the exceptional durability. Herein, the long‐term stability of HTL‐free carbon‐based PSCs (H‐C‐PSCs) in the ambient air environment is investigated to thoroughly understand and identify the governing chemistry during the degradation. Specifically, a reversible degradation phenomenon is observed along with an anomalous S‐shape of current–voltage curves involving only reduction of fill factor (FF), almost without impact for short‐circuit current density and open‐circuit voltage. Furthermore, a minute‐heating treatment will eliminate the reversible degradation which can be attributed to the reversible formation of intermediate hydrate at the interface between perovskite and carbon contact. This provides a new perspective for the stability issue of H‐C‐PSCs. [ABSTRACT FROM AUTHOR]

Halide solid electrolytes (HSEs) could be coated on high-voltage oxide cathodes at molecular-level via a solution process, which is highly favorable for reducing the interface impedance. However, during the preparation of composite cathodes, hydrate intermediates of HSEs are easily hydrolyzed to produce inactive impurities. In this work, the vacuum drying assisted method facilitates the generation of pure Li3InCl6 (LIC) on the surface of LiCoO2 (LCO) to improve the electrolyte/electrode solid–solid interface as well as the electrochemical stability of solid electrolyte under high voltage. By introducing Li7P3S11 as an anode buffer layer, 30 wt. %-LIC-coated LCO demonstrates high specific capacity of 121.7 mAh g−1 and good cycling stability. Our study highlights a promising method to build advanced composite cathodes for all-solid-state batteries. [ABSTRACT FROM AUTHOR]

Elemental sulfur possesses an ultra‐high theoretical specific capacity, while the practical application of sulfur in lithium–sulfur (Li–S) batteries is seriously hindered by the sluggish redox kinetics and serious shuttle effect. Enhancing the catalytic activity of the sulfur host by a rational structural design is the key to address these issues. Herein, for the first time, concave‐nanocubic (CNC) nickel–platinum (Ni–Pt) alloys bounded by high‐index facets (HIFs) are introduced as the core catalyst of sulfur for Li–S batteries. It is demonstrated that the CNC Ni–Pt alloy crystallites dispersed uniformly on graphene exhibit a high electrochemical activity to drive the conversion from intermediate lithium polysulfides to solid discharged products. Benefiting from the accelerated redox kinetics by HIFs, the cathode delivers a low capacity damping of 0.025% per cycle for 1000 cycles at 1 C rate. In particular, a high reversible capacity of 664.9 mAh g−1‐cathode with cathode as active material can be achieved with high sulfur loading (8.8 mg cm−2) and low electrolyte usage (5 µL mgs−1). This study focuses on improving the catalytic activity of sulfur hosts by modulating the exposed facets of core catalyst and provides a new path for the structure optimizing of host materials in Li–S batteries. [ABSTRACT FROM AUTHOR]

Lithium‐metal (Li) electrode has been regarded as an excellent option to increase the energy density of next‐generation secondary batteries due to its low electrochemical potential and ultrahigh theoretical capacity. However, Li electrodes suffer from poor Coulombic efficiency (CE) and uneven lithium deposition issues during cycling that severely restrain its application. Herein, ammonium perfluoro(2‐methyl‐3‐oxahexanoate) (APFA), a pragmatic anionic surfactant, is introduced as an electrolyte additive to regulate the deposition behavior of lithium. Different from the conventional sacrificial additives that reinforce solid electrolyte interphase (SEI) layers on Li electrodes, the PFA− anions are mainly adsorbed on the Li surface, which improves the electron transfer step kinetics due to the ψ1 effect. The introduction of APFA in the electrolyte promises homogeneous and highly dense lithium deposition and the LiLi symmetric cell with APFA can operate over 4000 h with excellent stability and low polarization. This work provides a facile and promising strategy for fabricating stable Li anode for high‐energy‐density secondary batteries. [ABSTRACT FROM AUTHOR]

Li‐rich Mn‐based layered oxides are regarded as the most promising cathode materials for advanced lithium‐ion batteries with energy density as high as 400 Wh kg−1. However, decline of capacity and discharge potential derived from phase transformation during cycling is still an obstacle for practical utilization of Li‐rich cathode materials. Undoubtedly, an in‐depth understanding origin and evolution of the phase transformation from bottom to top is crucial to solve the problem finally. Herein, the recent representative progress on Li‐rich cathode materials from top to bottom is summarized: starting from relationship between dimensions and performance, to evolution of phase transformation, finally to participation of anions during charge–discharge cycling. It systematically shows what happens in the different microscopic levels and how these phenomena relate to cycling of Li‐rich cathode materials with the help of emerging state‐of‐the‐art characterization techniques. On the basis of this progress, it is proposed that rational structural design can fully play its role to build high‐performance energy storage materials and enhance structural stability. [ABSTRACT FROM AUTHOR]

Rutile TiO2 (R‐TiO2) produced by chemical bath deposition (CBD) is widely considered as the desired electron transport layer (ETL) for perovskite solar cells (PSCs). However, the understanding of the growth mechanism of R‐TiO2 ETL and its general regular pattern affecting power conversion efficiency (PCE) is underappreciated. Herein, the growth mechanism of TiO2 on fluorine‐doped SnO2 substrate (FTO) is demonstrated and it is revealed that pure R‐TiO2, rather than a rutile/anatase mixed crystal, is formed under an Sn–Ti isostructural substitution effect. The similarity of lattice parameters and phase structure between FTO and R‐TiO2 can reduce interface misfit and nucleation barrier, thus boosting heterogeneous nucleation and growth of R‐TiO2 simultaneously. Based on the key growth conditions of the R‐TiO2 ETL, the dominant distribution of PCE for hole transport layer (HTL)‐free carbon‐based planar perovskite solar cells is illustrated and discussed, and a champion efficiency of 14.0% is achieved. [ABSTRACT FROM AUTHOR]