ABSTRACT Two-dimensional carbides and nitrides of transition metals, known as MXenes, are a fast-growing family of materials that have attracted attention as energy storage materials. MXenes

are mainly prepared from Al-containing MAX phases (where A = Al) by Al dissolution in F-containing solution; most other MAX phases have not been explored. Here a redox-controlled A-site

etching of MAX phases in Lewis acidic melts is proposed and validated by the synthesis of various MXenes from unconventional MAX-phase precursors with A elements Si, Zn and Ga. A negative

electrode of Ti3C2 MXene material obtained through this molten salt synthesis method delivers a Li+ storage capacity of up to 738 C g−1 (205 mAh g−1) with high charge–discharge rate and a

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subscriptions * Read our FAQs * Contact customer support SIMILAR CONTENT BEING VIEWED BY OTHERS DOUBLE TRANSITION METAL MXENE (TIXTA4−XC3) 2D MATERIALS AS ANODES FOR LI-ION BATTERIES Article

Open access 12 January 2021 LI-ION STORAGE PROPERTIES OF TWO-DIMENSIONAL TITANIUM-CARBIDE SYNTHESIZED VIA FAST ONE-POT METHOD IN AIR ATMOSPHERE Article Open access 24 August 2021 BOOSTING

THE INTERFACIAL SUPERIONIC CONDUCTION OF HALIDE SOLID ELECTROLYTES FOR ALL-SOLID-STATE BATTERIES Article Open access 28 April 2023 DATA AVAILABILITY Source data for Figs. 2a,d and 4 are

provided with the paper. The remaining data that support the findings of this study are available from the corresponding authors upon reasonable request. CHANGE HISTORY * _ 18 JANUARY 2021 A

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financially by the National Natural Science Foundation of China (grant nos. 21671195, 91426304, 51902320 and 51902319) and by the China Postdoctoral Science Foundation (grant no.

2018M642498). H.S. was supported by a grant from the China Scolarship Council. P.S., P.L.T. and H.S. thank the Agence Nationale de la Recherche (Labex STORE-EX) for financial support. Q.H.

thanks the International Partnership Program of Chinese Academy of Sciences (grant no. 174433KYSB20190019), the Leading Innovative and Entrepreneur Team Introduction Program of Zhejiang, and

the Ningbo top-talent team program for financial support. Z.L. is supported by the Fundamental Research Funds for the Central Universities (grant no. YJ201886). We acknowledge the Swedish

Government Strategic Research Area in Materials Science on Functional Materials at Linköping University (faculty grant SFO‐Mat‐LiU no. 2009 00971). The Knut and Alice Wallenberg Foundation

is acknowledged for support of the electron microscopy laboratory in Linköping, a Fellowship grant (P.E) and a scholar grant (L.H., 2016-0358). AUTHOR INFORMATION Author notes * These

authors contributed equally: Youbing Li, Hui Shao. AUTHORS AND AFFILIATIONS * Engineering Laboratory of Advanced Energy Materials, Ningbo Institute of Materials Technology and Engineering,

Chinese Academy of Sciences, Ningbo, China Youbing Li, Mian Li, Ke Chen, Xian-Hu Zha, Shiyu Du, Zhifang Chai & Qing Huang * University of Chinese Academy of Sciences, Beijing, China

Youbing Li * CIRIMAT, Université de Toulouse, CNRS, Toulouse, France Hui Shao, Liyuan Liu, Benjamin Duployer, Patrick Rozier, Pierre-Louis Taberna & Patrice Simon * Réseau sur le

Stockage Electrochimique de l’Energie (RS2E), CNRS, Amiens, France Hui Shao, Liyuan Liu, Benjamin Duployer, Patrick Rozier, Encarnacion Raymundo-Piñero, Pierre-Louis Taberna & Patrice

Simon * College of Materials Science and Engineering, Sichuan University, Chengdu, China Zifeng Lin * Thin Film Physics Division, Department of Physics, Chemistry, and Biology (IFM),

Linköping University, Linköping, Sweden Jun Lu, Per O. Å. Persson, Per Eklund & Lars Hultman * CNRS, CEMHTI UPR3079, Université Orléans, Orléans, France Encarnacion Raymundo-Piñero *

Institut Universitaire de France, Paris, France Patrice Simon Authors * Youbing Li View author publications You can also search for this author inPubMed Google Scholar * Hui Shao View author

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author inPubMed Google Scholar * Patrick Rozier View author publications You can also search for this author inPubMed Google Scholar * Zhifang Chai View author publications You can also

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Huang View author publications You can also search for this author inPubMed Google Scholar CONTRIBUTIONS Q.H., Z.L., P.-L.T. and P.S. designed the research. Y.L. conducted material

preparations and most of the characterization. H.S. and L.L. conducted the electrochemical tests and Z.L., P.-L.T. and P.S. analysed the data. H.S., B.D. and P.R. carried out the in situ

XRD. J.L., P.O.Å.P, P.E. and L.H. carried out the STEM measurements. E.R.-P. performed the temperature-programmed desorption/mass spectrometry. Z.L., P.S. and Q.H. prepared the manuscript.

All authors contributed to the discussion of the data and writing the paper. CORRESPONDING AUTHORS Correspondence to Zifeng Lin, Patrice Simon or Qing Huang. ETHICS DECLARATIONS COMPETING

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Source Data for Fig. 2a,d. SOURCE DATA FIG. 4 Source Data for Fig. 4. RIGHTS AND PERMISSIONS Reprints and permissions ABOUT THIS ARTICLE CITE THIS ARTICLE Li, Y., Shao, H., Lin, Z. _et al._

A general Lewis acidic etching route for preparing MXenes with enhanced electrochemical performance in non-aqueous electrolyte. _Nat. Mater._ 19, 894–899 (2020).

https://doi.org/10.1038/s41563-020-0657-0 Download citation * Received: 19 September 2019 * Accepted: 05 March 2020 * Published: 13 April 2020 * Issue Date: 01 August 2020 * DOI:

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