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transition-metal carbide materials termed MXene have attracted huge attention in the field of electrochemical energy storage. To this end, MXenes whose capability depends on the M transition elements represent a new paradigm extending beyond the realm of oft-explored elemental 2D materials beginning with graphene. However, the as-prepared MXenes suffer from unsatisfied capability due to the loss M elements during the etching process for the preparation of MXenes. Here, taking Ti 3 C 2 T x as an example, we demonstrate that nitrogen and vanadium incorporation by means of microwave irradiation in NH 4 VO 3 -containing ethylene glycol can significantly improve the electrochemical performance of multilayered Ti 3 C 2 T x MXene. While maintaining the 2D structure of MXene layers, the N and V elements are incorporated between the Ti 3 C 2 T x MXene interlayers in the forms of C−V−OH, C−V−O, V−O, and Ti−O−N species. Specifically, at a V:Ti atomic ratio of about 1:30 (N:Ti = 0.29), N and V incorporation between the Ti 3 C 2 T x interlayers gives rise to an increase in capability by about 40%, corresponding to an impressive reversible capacity of 92 mA h g −1 at 3 C rate after 1000 cycles. These results demonstrate that N (V)-incorporated Ti 3 C 2 T x MXenes offer fascinating potential for high-performance electrode materials and provide guidelines for designing and engineering anode materials.

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As a rapidly growing family of 2D transition metal carbides and nitrides, MXenes are recognized as promising materials for the development of future electronics and optoelectronics. So far, the reported patterning methods for MXene films lack efficiency, resolution, and compatibility, resulting in limited device integration and performance. Here, a high‐performance MXene image sensor array fabricated by a wafer‐scale combination patterning method of an MXene film is reported. This method combines MXene centrifugation, spin‐coating, photolithography, and dry‐etching and is highly compatible with mainstream semiconductor processing, with a resolution up to 2 µm, which is at least 100 times higher than other large‐area patterning methods reported previously. As a result, a high‐density integrated array of 1024‐pixel Ti3C2Tx/Si photodetectors with a detectivity of 7.73 × 1014 Jones and a light–dark current ratio (Ilight/Idark) of 6.22 × 106, which is the ultrahigh value among all reported MXene‐based photodetectors, is fabricated. This patterning technique paves a way for large‐scale high‐performance MXetronics compatible with mainstream semiconductor processes.