Bottom-up synthesis of graphene films hosting atom-thick molecular-sieving apertures.

Autor:	Villalobos LF; Laboratory of Advanced Separations, École Polytechnique Fédérale de Lausanne, Sion 1950, Switzerland., Van Goethem C; Laboratory of Advanced Separations, École Polytechnique Fédérale de Lausanne, Sion 1950, Switzerland., Hsu KJ; Laboratory of Advanced Separations, École Polytechnique Fédérale de Lausanne, Sion 1950, Switzerland., Li S; Laboratory of Advanced Separations, École Polytechnique Fédérale de Lausanne, Sion 1950, Switzerland., Moradi M; Laboratory of Advanced Separations, École Polytechnique Fédérale de Lausanne, Sion 1950, Switzerland., Zhao K; Laboratory of Advanced Separations, École Polytechnique Fédérale de Lausanne, Sion 1950, Switzerland., Dakhchoune M; Laboratory of Advanced Separations, École Polytechnique Fédérale de Lausanne, Sion 1950, Switzerland., Huang S; Laboratory of Advanced Separations, École Polytechnique Fédérale de Lausanne, Sion 1950, Switzerland., Shen Y; Laboratory of Advanced Separations, École Polytechnique Fédérale de Lausanne, Sion 1950, Switzerland., Oveisi E; Interdisciplinary Centre for Electron Microscopy, École Polytechnique Fédérale de Lausanne, Lausanne 1015, Switzerland., Boureau V; Interdisciplinary Centre for Electron Microscopy, École Polytechnique Fédérale de Lausanne, Lausanne 1015, Switzerland., Agrawal KV; Laboratory of Advanced Separations, École Polytechnique Fédérale de Lausanne, Sion 1950, Switzerland; kumar.agrawal@epfl.ch.
Jazyk:	angličtina
Zdroj:	Proceedings of the National Academy of Sciences of the United States of America [Proc Natl Acad Sci U S A] 2021 Sep 14; Vol. 118 (37).
DOI:	10.1073/pnas.2022201118
Abstrakt:	Incorporation of a high density of molecular-sieving nanopores in the graphene lattice by the bottom-up synthesis is highly attractive for high-performance membranes. Herein, we achieve this by a controlled synthesis of nanocrystalline graphene where incomplete growth of a few nanometer-sized, misoriented grains generates molecular-sized pores in the lattice. The density of pores is comparable to that obtained by the state-of-the-art postsynthetic etching (10 12 cm -2 ) and is up to two orders of magnitude higher than that of molecular-sieving intrinsic vacancy defects in single-layer graphene (SLG) prepared by chemical vapor deposition. The porous nanocrystalline graphene (PNG) films are synthesized by precipitation of C dissolved in the Ni matrix where the C concentration is regulated by controlled pyrolysis of precursors (polymers and/or sugar). The PNG film is made of few-layered graphene except near the grain edge where the grains taper down to a single layer and eventually terminate into vacancy defects at a node where three or more grains meet. This unique nanostructure is highly attractive for the membranes because the layered domains improve the mechanical robustness of the film while the atom-thick molecular-sized apertures allow the realization of large gas transport. The combination of gas permeance and gas pair selectivity is comparable to that from the nanoporous SLG membranes prepared by state-of-the-art postsynthetic lattice etching. Overall, the method reported here improves the scale-up potential of graphene membranes by cutting down the processing steps. Competing Interests: The authors declare no competing interest.
Databáze:	MEDLINE
Externí odkaz:	Zobrazit plný text záznamu