Micro‐blooming: hierarchically porous nitrogen‐doped carbon flowers derived from metal‐organic mesocrystals

Hwang, J., Walczak, R., Oschatz, M., Tarakina, N. V. and Schmidt, B. V.K.J. (2019) Micro‐blooming: hierarchically porous nitrogen‐doped carbon flowers derived from metal‐organic mesocrystals. Small, 15(37), 1901986. (doi: 10.1002/smll.201901986) (PMID:1264774)

Abstract

Synthesis of 3D flower‐like zinc‐nitrilotriacetic acid (ZnNTA) mesocrystals and their conformal transformation to hierarchically porous N‐doped carbon superstructures is reported. During the solvothermal reaction, 2D nanosheet primary building blocks undergo oriented attachment and mesoscale assembly forming stacked layers. The secondary nucleation and growth preferentially occurs at the edges and defects of the layers, leading to formation of 3D flower‐like mesocrystals comprised of interconnected 2D micropetals. By simply varying the pyrolysis temperature (550–1000 °C) and the removal method of in the situ‐generated Zn species, nonporous parent mesocrystals are transformed to hierarchically porous carbon flowers with controllable surface area (970–1605 m2 g−1), nitrogen content (3.4–14.1 at%), pore volume (0.95–2.19 cm3 g−1), as well as pore diameter and structures. The carbon flowers prepared at 550 °C show high CO2/N2 selectivity due to the high nitrogen content and the large fraction of (ultra)micropores, which can greatly increase the CO2 affinity. The results show that the physicochemical properties of carbons are highly dependent on the thermal transformation and associated pore formation process, rather than directly inherited from parent precursors. The present strategy demonstrates metal‐organic mesocrystals as a facile and versatile means toward 3D hierarchical carbon superstructures that are attractive for a number of potential applications.

• Item Type: Articles
• Additional Information: The authors acknowledge the financial support from Max Planck Society. J.H. acknowledges Max Planck Society for a Postdoc scholarship.
• Status: Published
• Refereed: Yes
• Glasgow Author(s) Enlighten ID: Schmidt, Dr Bernhard
• Authors: Hwang, J., Walczak, R., Oschatz, M., Tarakina, N. V., and Schmidt, B. V.K.J.
• College/School: College of Science and Engineering > School of Chemistry
• Journal Name: Small
• Publisher: Wiley
• ISSN: 1613-6810
• ISSN (Online): 1613-6829
• Published Online: 02 July 2019
• Copyright Holders: © 2019 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim
• First Published: First published in Small 15(37):1901986
• Publisher Policy: Reproduced in accordance with the publisher copyright policy