A Special Collection on 2D Materials and Their Applications

The guest editors Dan Zhao and Xinliang Feng provided a brief overview of the field and highlight the state-of-the-art contributions featured in this special collection. The field of 2D materials and their applications has exploded since 2004, when graphene was successfully prepared by Geim, Novoselov and co-workers.¹ In the subsequent decade-and-a-half, the scientific community has shown great enthusiasm for studying graphene and graphene-analogous 2D materials, including the transition metal dichalcogenides (TMDs), graphitic carbon nitride (g-C₃N₄), hexagonal boron nitride (h-BN), black phosphorus (BP), MXenes, silicene, etc.² Very recently, organic 2D crystalline materials such as single- to few-layer 2D metal-organic frameworks (MOFs)³, 2D polymers⁴ and 2D covalent organic frameworks (COFs)⁵ with large surface areas, diverse functionalities, and high chemical stabilities have been regarded as an emerging member of the family of 2D materials. The availability of these 2D materials has also experienced an impressive growth over the past decade that finds a prolific manifestation in numerous applications, including sensors, opto-electronics, chemical separations, drug-delivery systems, and other energy and environmentally related applications.

Despite the exciting achievements in the field of 2D materials and their applications, challenges still exist. The studies on emerging 2D materials and their van der Waals layer-stacked structures such as graphdiyne, 2D MOFs, 2D COFs, and their applications are still in the infant stage. Large-scale production of 2D materials with high quality and controlled structures has yet to be realized for ultimate industrialization. Furthermore, the precise manipulation of thicknesses, functionalities, topologies, crystal phases, and lateral sizes of 2D materials is still challenging. Commercializing 2D materials will be a major milestone, and we still need to contribute ongoing efforts to achieve this goal. Targeting at these goals, here, we are greatly honored to assemble a compendium of the latest studies on 2D materials and their applications, covering a wide array of topics.

The articles selected in this collection have a multidisciplinary nature and include contributions of more than twenty research groups, whose research ranges from the design, synthesis, and characterization of advanced 2D materials to their applications in various directions. Eight Minireviews present overviews on 2D graphdiyne, 2D MOFs, 2D COFs, silicate materials, and g-C₃N₄ in fascinating applications, including electrochemistry, electromagnetic shielding/absorbing, catalysis, supercapacitors, sensors, gas adsorption/separation, water pollution removal, energy conversion, and electrochromic switching. One Communication and twelve Full Papers report new research results on synthesizing advanced 2D MOFs, COFs, layered double hydroxides, MXenes, perovskites, and graphene oxide materials for membrane separations, adsorption, electrocatalysis, sodium-ion batteries, etc.

In summary, this special collection aims to provide the recent state-of-the-art progress in 2D materials and their applications. We strongly believe that the compilation of these excellent review and research articles covering broad topics related to 2D materials and their applications could benefit researchers in diverse fields. We hope this collection could provide the readers with some representative and exciting views regarding the new developments and applications of 2D materials. Toward this end, we would like to express our sincere gratitude toward the authors and the editorial staff for their great contributions to this special collection.

Reference: [1] K. S. Novoselov, A. K. Geim, S. V. Morozov, D. Jiang, Y. Zhang, S. V.Dubonos, I. V. Grigorieva, A. A. Firsov, Science 2004, 306, 666–669. [2] H. Zhang, Chem. Rev. 2018, 118, 6089–6090. [3] M. T. Zhao, Y. Huang, Y. W. Peng, Z. Q. Huang, Q. L. Ma, H. Zhang, Chem. Soc. Rev. 2018, 47, 6267–6295. [4] K. J. Liu, H. Y. Qi, R. H. Dong, R. Shivhare, M. Addicoat, T. Zhang, H. Sahabudeen, T. Heine, S. Mannsfeld, U. Kaiser, Z. K. Zheng, X. L. Feng, Nat. Chem. 2019, 11, 994–1000. [5] D. Rodriguez-San-Miguel, C. Montoro, F. Zamora, Chem. Soc. Rev. 2020, 49, 2291–2302.  doi.org/10.1002/asia.202101283