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Abstract Integration of metal‐organic frameworks (MOFs) as components of advanced electronic devices is at a very early phase of development and the fundamental issues related to their crystal growth on conductive substrate need to be addressed. Herein, we report on the structural characterization of a newly synthesized Sr‐based MOF {[Sr(2,5‐Pzdc)(H2O)2] ⋅ 3 H2O}n (1) and the uniform crystal growth of compound 1 on a conducting glass (fluorine doped tin oxide (FTO)) substrate using electrochemical deposition techniques. The Sr‐based MOF 1 was synthesized by the reaction of Sr(NO3)2 with 2,5‐pyrazinedicarboxylic acid dihydrate (2,5‐Pzdc) under solvothermal conditions. A single‐crystal X‐ray diffraction analysis revealed that 1 has a 3D structure and crystallizes in the triclinic P1‾ space group. In addition, the uniform crystal growth of this MOF on a conducting glass (FTO) substrate was successfully achieved using electrochemical deposition techniques. Only a handful of MOFs have been reposed to grown on conductive surfaces, which makes this study an important focal point for future research on the applications of MOF‐based devices in microelectronics.

Manipulating building-block nanomaterials to form an ordered superstructure in a dilute and spacer-free solution phase challenges the existing 5-nm node lithography and nanorobotics. The cooperative nature of nanocrystals, polymers, and cells can lead to superarrays or colloidal crystals. For known highly ordered systems, the characteristic length of materials, defined as the shortest dimension of objects, is generally larger than their separations. A spacer (small-molecule surfactant or polymer) is typically required to diminish short range van der Waals attraction, which results in a glassy or liquid state. Herein we propose a new concept of achieving highly ordered nano-objects in a dilute and spacer-free system via the synergistic effects of excellent solvation and appropriate constraints on rotational motion. As a proof of concept, this study demonstrates that aluminosilicate nanotubes (AlSiNTs) suspended in water under dilute conditions (e.g., 1.0 wt%) can spontaneously form hexagonal arrays with an intertubular distance as large as tens of nanometers. The separation distance of the ordered superstructure is also tunable via controlling the concentration and length of nanotubes. These superaligned structures are probed using small-angle x-ray scattering and cryo-TEM characterizations, with underlying mechanisms investigated at an atomic level using molecular dynamics simulations. The concept and discovery of this work can open up opportunities to a variety of applications including visible-UV photonics and nanolithography, and may be generalizable to other nano-object systems that fulfill similar requirements. [ABSTRACT FROM AUTHOR]