丰富氧缺陷MnO_(x)掺杂的碳纳米纤维基锌离子电池阴极材料的制备及性能EI北大核心CSCD

可充电水系锌离子电池(ZIBs)由于性能优良、价格低廉、环境友好等优点而被广泛研究,而针对高容量、长循环寿命的ZIBs阴极结构设计成为该领域研究的热点。采用同轴静电纺丝法,以PAN溶液为皮层,含有Mn(NO_(3))_(2)·xH_(2)O的PAN溶液为芯层制备纳米纤维膜,并对其炭化后得到了一种表面具有类皮脂腺凸起结构的碳纳米纤维(MCNFs),在其表面电化学沉积MnO_(2),制得了与电解液具有优良亲和性的MnO_(2)@MCNFs阴极材料。研究表明:设计得到的类皮脂腺结构不仅增大了阴极比表面积,而且在MCNFs基底与电化学沉积的α-MnO_(2)活性物质之间形成铆接效应,加固了界面结合,减少活性物质脱落,降低界面电阻,缩短了电子传导和离子扩散路径。对其电化学性能进行测试,芯层Mn(NO_(3))_(2)·xH_(2)O含量为3%的阴极在100 mA/g的电流密度下,首周次比容量达581.16 mAh/g;在1 A/g电流密度下循环1000周次后比容量仍大于120 mAh/g,库仑效率保持在99%左右。     

Coupling Engineering of NH4+ Pre-Intercalation and Rich Oxygen Vacancies in Tunnel WO3 Toward Fast and Stable Rocking Chair Zinc-Ion Battery

Herein, for the first time, a pre-intercalated non-metal ion (NH₄⁺) with rich oxygen vacancies stabilized tunnel WO₃ is proposed as a new intercalation anode to construct Zn-metal-free rocking-chair ZIBs. With the ethylene glycol additive in the aqueous electrolyte, the Zn²⁺ solvation structure can be regulated and the side reaction of hydrogen evolution can also be suppressed. Owing to the integrated synergetic modification, a high-rate and ultra-stable aqueous Zn-(NH₄)_xWO₃ battery can be constructed, which exhibits an improved specific capacity (153 mAh g⁻¹ at 0.1 A g⁻¹), excellent rate performance (when the current density increases to 3 A g⁻¹, the specific capacitance is still 86 mAh g⁻¹), and a high cycle stability with 100% capacity retention after 2,200 cycles under 5 A g⁻¹. Ex situ X-ray diffraction and XPS reveal the reversible insertion/extraction of Zn²⁺ in (NH₄)_xWO₃. The assembled (NH₄)_xWO₃//MnO₂ rocking-chair ZIBs delivers excellent capacity of 82 mAh g⁻¹ at 0.1 A g⁻¹, impressive cyclic stability. Additionally, the flexible (NH₄)_xWO₃//MnO₂ ZIBs can power the electrochromic device-based PANI/WO₃ with high color contrast and fast response time. This study provides new insight for developing high-performance rechargeable aqueous ZIBs.     

Insights on Artificial Interphases of Zn and Electrolyte: Protection Mechanisms,Constructing Techniques,Applicability, and Prospective

Aqueous zinc-ion batteries (ZIBs) with metallic Zn anodes have emerged as promising candidates for large-scale energy storage systems due to their inherent safety and competitive capacity. However, challenges of Zn anodes, including dendrite growth and side reactions, impede the commercialization of ZIBs. The regulation of the Zn/electrolyte interphase is a feasible method to achieve high-performance ZIBs with prolonged lifespan and high reversibility. Considering the as-made artificial interphase is the result of a combination of protection materials, protection mechanisms, and construction techniques, this review comprehensively summarizes the recent progress of interphase modulation and provides a systematic guideline for constructing ideal artificial layers. In addition to revealing the entanglement relationship between the failure behaviors of Zn anodes and timely concluding the emerging protection mechanisms for stable Zn/electrolyte interphase, this review also evaluates the constructing techniques in regard of commercialization, including engineering workflow, strength, shortcoming, applicable materials, and protection effect, aiming to pave the way to practical application. Finally, this review presents noteworthy points of ideal artificial layer. It is expected that this review can enlighten researchers to not only explore ideal interphases of Zn anodes for practical application, but also design other metal anodes in aqueous batteries with similar failure behaviors.