Journal of Materials Chemistry A
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2026
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IF 9.2
Shaoyan Huang,Shuling Liu,Sha Fan,Rui Su,Libo Liu,Deliang Tian,Jinbao Li,Jianbo Tong
Manganese-based cathode materials are highly promising for large-scale aqueous zinc-ion batteries (AZIBs) due to their high specific capacity, low cost, and environmental benignity. However, structural instability and severe Mn dissolution at the cathode/electrolyte interface during cycling lead to rapid capacity degradation, which greatly limits their practical application. To address these critical issues, this work proposes an innovative Mo/N cation–anion co-doping strategy for δ-MnO2, which differs from single Mo or N doping and achieves synergistic optimization of structural and electrochemical properties. Specifically, Mo doping effectively modulates the lattice parameters of δ-MnO2 to expand ion diffusion channels, while N doping strengthens the layered framework and suppresses Mn dissolution. Their synergistic effect significantly enhances electronic conductivity and structural robustness compared with single-doped or pristine δ-MnO2 samples. The optimized Mo0.1/N1-δ-MnO2 cathode delivers a high discharge specific capacity of 370.8 mAh g−1 at 0.2 A g−1, retaining 270.0 mAh g−1 after 200 cycles; it also delivers 140.0 mAh g−1 at a high current density of 1 A g−1 and still retains a capacity of 80.6 mAh g−1 after 800 cycles. Combined with in situ EIS, ex situ XRD, and DFT calculations, the underlying mechanism is quantitatively revealed through Mo/N co-doping induced reduction of the Zn2+ diffusion barrier, optimization of ion migration pathways, and regulation of the reversible Zn2+/H+ co-intercalation mechanism. This work provides clear mechanistic insights and establishes a reliable cation–anion co-doping design principle for high-performance Mn-based AZIB cathodes.
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高影响因子
JOURNAL OF POWER SOURCES
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2026
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IF 7.9
Shaolin Yang,Panpan Fu,Zexi Chen,Shihao Chang,Qianqian Song,Jiandong Wu,Tong Xue,Chunping Hou,Zhilin Sheng
The practical application of manganese dioxide (MnO 2 ) in Zn-ion batteries (ZIBs) is hindered by intrinsic limitations such as low electronic conductivity, slow ion diffusion, and structural instability. To address these challenges, we report a Co-doped δ-MnO 2 /MXene composite (CMM) cathode, fabricated via a facile one-step room-temperature synthesis. This design creates a synergistic coupling effect, where MXene provides a conductive scaffold while cobalt doping modulates the electronic structure of MnO 2 . This dual modification collectively enhances electrical conductivity, expands the active surface area, and significantly accelerates ion diffusion kinetics. As a ZIB cathode, the CMM electrode demonstrates exceptional charge storage performance: delivering a high specific capacity of 480.9 mAh g −1 at 0.1 A g −1 , and exhibiting exceptional long-term durability with over 100 % capacity retention after 2000 cycles at 1 A g −1 . Remarkably, it achieves an outstanding energy density of 651.6 Wh kg −1 at a power density of 135.5 W kg −1 , significantly outperforming both δ-MnO 2 /MXene (MM) and pristine δ-MnO 2 cathodes. This work establishes an effective synergistic regulation strategy and provides profound insights into the design of high-performance cathode materials for advanced energy storage systems.
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高影响因子
ACS Applied Materials & Interfaces
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2022
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IF 10.383
Qianlin Huang,Puzhen Zhao,Weiwei Wang,Lu Lv,Weiming Zhang,Bingcai Pan
Cost-efficient and durable manganese-based catalysts are in great demand for the catalytic elimination of volatile organic compounds (VOCs), which are dominated not only by the nanostructures but also by the oxygen vacancies and Mn–O bond in the catalysts. Herein, a series of nanostructured Co–Fe-doped-δ-MnO2 catalysts (Co–Fe-δ-MnO2) with high dispersion were in situ fabricated by employing metal–organic-frameworks (MOFs) as reducing agents, dopants, and templates all at the same time. The as-obtained Co–Fe-δ-MnO2-20% catalyst exhibited robust durability and high catalytic activity (225 °C) for toluene combustion even in the presence of 5 vol % water vapor, which is 50 °C lower than that of pristine δ-MnO2. Various characterizations revealed that the homogeneously dispersed codoping of Co and Fe ions into δ-MnO2 promotes the generation of oxygen vacancies and weakens the strength of the Mn–O bond, thus increasing the amount of adsorbed oxygen (Oads) and improving the mobility of lattice oxygen (Olatt). Meanwhile, due to successfully inheriting the framework structures of MOFs, the obtained catalyst exhibited a high surface area and three-dimensional mesoporous structure, which contributes to diffusion and increases the number of active sites. Moreover, in situ DRIFTS results confirmed that the toluene degradation mechanism on the Co–Fe-δ-MnO2-20% follows the MVK mechanism and revealed that more Oads and high-mobility Olatt induced by this novel method contribute to accumulating and mineralizing key intermediates (benzoate) and thus promote toluene oxidation. In conclusion, this work stimulates the opportunities to develop Co–Fe-δ-MnO2 as a class of nonprecious-metal-based catalysts for controlling VOC emissions.
研究领域:
环境科学
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材料科学
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高影响因子
Journal of the American Chemical Society
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2024
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IF 14.4
Luhan Wei,Yang Hu,Yiwei Huang,Ying Lu,Zihan Xu,Nian Zhang,Qiyang Lu
Redox-active transition metal oxides (TMOs) play crucial roles in diverse energy storage and conversion technologies, such as batteries and pseudocapacitors. These materials show intricate electrochemical charge storage processes, encompassing both bulk ion-intercalation, typical of battery electrodes, and pseudocapacitive-like behavior localized near the surfaces. However, understanding the underlying mechanisms of charge storage in redox-active TMOs is challenging due to the coexistence of these behaviors. In this study, we propose an integrated approach that combines operando electrochemical and optical techniques to disentangle the contributions of bulk and surface phenomena. Using birnessite δ-MnO2–x as a model system, we account for surface pseudocapacitive-like layers and employ a refined model that incorporates both surface reactions and bulk chemical diffusion. This methodology allows us to extract essential kinetic parameters, establishing a fundamental framework for unraveling surface and bulk electrochemical processes. This advancement provides a valuable tool for the rational design of energy storage devices, enhancing our ability to tailor these materials for specific applications.
研究领域:
材料科学
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电化学
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能量存储
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高影响因子
危险品化学品经营许可证（带存储）