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The aqueous micro batteries (AMBs) are expected to be one of the most promising micro energy storage devices for its safe operation and cost‐effectiveness. However, the performance of the AMBs is not satisfactory, which is attributed to strong interaction between metal ions and the electrode materials. Here, the first AMBs are developed with NH4+ as charge carrier. More importantly, to solve the low conductivity and the dissolution during the NH4+ intercalation/extraction problem of perylene material represented by perylene‐3,4,9,10‐tetracarboxylic dianhydride (PTCDA), the Ti3C2Tx MXene with high conductivity and polar surface terminals is introduced as a conductive skeleton (PTCDA/Ti3C2Tx MXene). Benefitting from this, the PTCDA/Ti3C2Tx MXene electrodes exhibit ultra‐high cycle life and rate capability (74.31% after 10 000 galvanostatic chargedischarge (GCD) cycles, and 91.67 mAh g−1 at 15.0 A g−1, i.e., capacity retention of 45.2% for a 30‐fold increase in current density). More significantly, the AMBs with NH4+ as charge carrier and PTCDA/Ti3C2Tx MXene anode provide excellent energy density and power density, cycle life, and flexibility. This work will provide strategy for the development of NH4+ storage materials and the design of AMBs. [ABSTRACT FROM AUTHOR]

Replacing Zn metal with intercalated materials as the aqueous zinc-ion batteries (AZIBs) anode is an effective strategy to solve serious zinc dendrites problem. MXene-based derived materials combine the advantages of both derivatives with excellent electrochemical activity and MXene with high electrical conductivity. Here, we report an in situ derived strategy for synthesizing H 2 Ti 3 O 7 −MXene from common Ti 3 C 2 MXene by one-step hydrothermal process with simultaneous alkalization and oxidation, followed by ion-exchange reaction. It is experimentally verified that H 2 Ti 3 O 7 −MXene exhibits an extremely low charging voltage of only 0.25 V, which has a satisfactory potential for AZIBs anodes. Through characterization analyses, H 2 Ti 3 O 7 −MXene nanoflowers consist of countless connectively interlaced and entangled nanoribbons, which shorten the ion diffusion path and accelerate Zn2+ diffusion kinetics. The synergistic effect between H 2 Ti 3 O 7 and MXene enables H 2 Ti 3 O 7 −MXene to achieve efficient and reversible Zn2+ (de)intercalation. Specifically, at 0.10 A g−1, the specific capacity of 61.20 mAh g−1 is achieved and no significant discharge specific capacity decline occurs at 0.60−2.00 A g−1. The assembled zinc ion full-cell (Zn x MnO 2 //H 2 Ti 3 O 7 −MXene) shows the excellent cyclic stability and good coulombic efficiency during 600 GCD cycles. This work proves the feasibility of MXene-based derivatives for AZIBs anode and sheds light on developing efficient intercalated MXene derived anodes. [Display omitted] • H 2 Ti 3 O 7 −MXene nanoflowers was in-situ derived from common Ti 3 C 2 MXene nanosheets. • H 2 Ti 3 O 7 −MXene exhibits an extremely low charging voltage of only 0.25 V. • The unique structure of H 2 Ti 3 O 7 −MXene facilitates ion transport and good performance. • Ex-XPS, XRD tests demonstrated the reversible intercalation/de-intercalation of Zn2+. • It sheds light on developing efficient intercalated MXene-derived anodes for AZIBs. [ABSTRACT FROM AUTHOR]