Synthesizing Cr-Based Two-Dimensional Conjugated Metal-Organic Framework Through On-Surface Substitution Reaction

Weiliang Zhong; Tingfeng Zhang; Dan Chen; Nuoyu Su; Guangyao Miao; Jiandong Guo; Long Chen; Zhengfei Wang; Weihua Wang

doi:10.1002/smll.202207877

Synthesizing Cr-Based Two-Dimensional Conjugated Metal-Organic Framework Through On-Surface Substitution Reaction

Small. 2023 May;19(21):e2207877. doi: 10.1002/smll.202207877. Epub 2023 Feb 26.

Authors

Weiliang Zhong^{1

2}, Tingfeng Zhang³, Dan Chen⁴, Nuoyu Su^{1

2}, Guangyao Miao¹, Jiandong Guo^{1

2

5}, Long Chen⁴, Zhengfei Wang³, Weihua Wang^{1

5}

Affiliations

¹ Beijing National Laboratory for Condensed Matter Physics and Institute of Physics, Chinese Academy of Sciences, Beijing, 100190, P. R. China.
² School of Physical Sciences, University of Chinese Academy of Sciences, Beijing, 100190, P. R. China.
³ Hefei National Research Center for Physical Sciences at the Microscale, CAS Key Laboratory of Strongly-Coupled Quantum Matter Physics, Department of Physics, University of Science and Technology of China, Hefei, Anhui, 230026, P. R. China.
⁴ State Key Laboratory of Supramolecular Structure and Materials, College of Chemistry, Jilin University, Changchun, 130012, P. R. China.
⁵ Songshan Lake Material Laboratory, Dongguan, Guangdong, 523808, P. R. China.

PMID: 36843315
DOI: 10.1002/smll.202207877

Abstract

A single-layer Cr₃ (HITP)₂ (HITP = 2,3,6,7,10,11-hexaiminotriphenylene) conjugated metal-organic framework (c-MOF) is synthesized under ultrahigh vacuum conditions by substituting Cr for Ni in Ni₃ (HITP)₂ template. As revealed by low-temperature scanning tunneling microscopy and scanning tunneling spectroscopy, while codeposition of Cr atoms and 2,3,6,7,10,11-hexaaminotriphenylene precursors produces irregular branches, crystalline Cr₃ (HITP)₂ frameworks are obtained by depositing Cr atoms to the Ni₃ (HITP)₂ templates. The density functional theory calculations reveal that the binding energy between Cr and HITP ligands is much higher than that for Ni, which hampers the growth of crystalline Cr₃ (HITP)₂ frameworks through direct coordination assembly but makes the substitution reaction energetically favorable. This work demonstrates a new strategy to prepare high-quality early-transition-metal-based c-MOFs under ultrahigh vacuum conditions.

Keywords: density functional calculations; metal-organic frameworks; on-surface synthesis; scanning tunneling microscopy; transition metal atoms.

Abstract

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