Gull, SannaSannaGullCheng, Hsu-ChenHsu-ChenChengLi, En-HaoEn-HaoLiChen, Tsung-YiTsung-YiChenNi, Chung-ShengChung-ShengNiYu, Wan-JuWan-JuYuChang, Hao-HsiangHao-HsiangChangWang, Ai-YinAi-YinWangDoong, Ruey-AnRuey-AnDoongCHIN-LUNG KUOChuang, Yu-ChunYu-ChunChuangChen, Bo-HaoBo-HaoChenChang, Chung-KaiChung-KaiChangChen, Hsin-Yi TiffanyHsin-Yi TiffanyChenChen, Han-YiHan-YiChen2026-03-162026-03-162026-02-1513858947https://www.scopus.com/record/display.uri?eid=2-s2.0-105028501991&origin=resultslisthttps://scholars.lib.ntu.edu.tw/handle/123456789/736373Aqueous zinc-ion batteries (AZIBs) offer strong potential for grid-scale energy storage, yet their performance is often constrained by sluggish Zn2+ diffusion and insufficiently stable cathode hosts. In this work, we develop a Mo-doped hydrated vanadium oxide (MoVOH/VOH) cathode designed to overcome these limitations. Using operando X-ray diffraction, operando XANES, and extended X-ray absorption fine structure (EXAFS) analysis combined with density functional theory (DFT) calculations, we not only elucidate the Zn2+ storage mechanism but also resolve the previously controversial structural position of Mo within the VOH framework. Our results demonstrate that high-oxidation-state Mo ions are predominantly incorporated substitutionally within the V-O layers, rather than occupying interlayer sites. This substitution significantly improves electronic conductivity, accelerates Zn2+ transport, and stabilizes the VOH lattice during repeated cycling. Consequently, the MoVOH/VOH cathode delivers a high capacity of 405 mAh g−1 at 0.1 A g−1, excellent rate capability, and 82% capacity retention after 300 cycles at 5 A g−1, and an energy density of ∼284 Wh kg−1 at 71 W kg−1. These findings demonstrate that Mo doping is an effective strategy for tailoring vanadium-based hosts for high-performance AZIBs and provide direct experimental and theoretical insight into the local structural role of Mo, addressing a key unresolved issue in hydrated vanadium oxides.falseAqueousCathode materialDFTOperando XANESOperando XRDjournal article10.1016/j.cej.2026.1733022-s2.0-105028501991