Synergistic tuning of d/p-band centers in Al-doped δ-MnO2 boosts kinetics and cyclability for aqueous Mg-ion storage

影响因子：17.9

DOI码：10.1016/j.nanoms.2026.02.011

发表刊物：Nano Materials Science

关键字：δ-MnO2, Al doping, D/p-band centers, Electronic structure, Aqueous magnesium-ion battery

摘要：Layered δ-MnO2 is a potential positive electrode for aqueous magnesium ion batteries (AMIBs), but its wide band gap, limited d/p-band centers interaction, and Mn dissolution during cycling restrict practical application. To address these critical issues, herein, nanoflower-like Al-doped δ-MnO2 (AlMO) is synthesized via a scalable hydrothermal-calcination method. Density Functional Theory (DFT) calculations reveal that Al substitution simultaneously optimizes three key electronic properties: (1) Reduces band gap (1.44 eV → 0.75 eV), enhancing intrinsic conductivity; (2) Upshifts the O 2p-band center (εp) from −3.24 eV to −2.64 eV and Mn 3d-band center (εd) from −1.79 eV to −1.60 eV; (3) reduces d/p-band centers differences (Δεd-p) from 1.45 eV to 1.04 eV, strengthening orbital hybridization. These adjustments boost Mg2+ adsorption capacity and accelerate charge transfer/ion diffusion kinetics. Importantly, by constructing the Mn-O-Al bonds to induce the d-band center at the Mn site to upward movement, the O 2p orbital electrons preferentially occupy the Mn-O bonding orbital, thereby significantly strengthening the Mn-O bonds and structural stability. As anticipated, the optimized AlMO positive electrode exhibits exceptional cyclic stability (about 93 % capacity retention after 1500 cycles) and satisfactory discharge capacity (168.3 mAh g−1, 67.5 % higher than pristine δ-MnO2 at 0.1 A g−1). The assembled AlMO//3,4,9,10-perylenetetracarboxylic diimide full cell also maintains a stable working state. This work establishes a precise electronic structure modulation strategy for δ-MnO2, providing an innovative approach to developing high-performance, long-cycle-life positive electrodes for AMIBs, and other aqueous rechargeable batteries.

合写作者：Wang Yang,Lv Tianming,Cui Miao,Zhou Zhenhua,Zhao Hongxin,Zhong Yi

论文类型：文章

通讯作者：Zhang Yifu*,Huang Chi *,Meng Changgong*

学科门类：理学

文献类型：J

卷号：XX

期号：X

页面范围：XX-XX, 2026

ISSN号：2589-9651

是否译文：否

CN号：50-1217/TB

收录刊物：SCI

发布期刊链接：https://doi-org-s.vpn.whu.edu.cn/10.1016/j.nanoms.2026.02.011

附件：

 1.nano materials sciences 2026.pdf