Fabrication of Ordered Macro‐Microporous Single‐Crystalline MOF and Its Derivative Carbon Material for Supercapacitor

Abstract

Because of their good performance in diffusion‐limited processes, ordered macro‐microporous single‐crystalline metal‐organic frameworks (MOFs) have potential for use in various fields. However, there are still very few reports of the synthesis of such MOFs. A general synthesis methodology for ordered macro‐microporous single‐crystalline MOFs is highly desired. Here, a novel strategy is reported for synthesizing single‐crystalline ordered macro‐microporous MOFs by monodentate‐ligand‐induced in situ crystallization within a 3D ordered hard template in a double‐solvent system. A space‐confined growth model is proposed to clarify the shaping effect of the template; the role of the monodentate ligand is also analyzed. Moreover, a carbon material derived from the macro‐microporous MOF inherits the ordered interconnected macroporous structure. The improved diffusion and lower resistance, as well as the structural robustness, endow the derivative carbon material with superior rate performance and excellent cycling stability when prepared as electrodes for a supercapacitor. It is anticipated that the method will provide new paths to the synthesis of such macro‐microporous materials for applications in energy‐related fields and beyond.

Porosity Engineering of MOF‐Based Materials for Electrochemical Energy Storage

“…Here, two strategies have been developed, i.e., templating and defect engineering. Similar to the report discussed before, [ 106 ] monodispersed PS spheres have been applied as templates to tailor macroporous structure of single‐crystal MOFs (ZIF‐8 [ 159 ] or HKUST‐1 [ 160 ] ). MOF‐derived carbons are further achieved with size‐tailored macropores after removal of PS templates, high‐temperature annealing (at 800–900 °C in Ar), and elimination of metal residuals.…”

“…A hierarchically interconnected macro–microporous carbon has been prepared by annealing of a single‐crystalline ordered interconnected macro–microporous Cu‐based MOF (denoted as SIM‐HKUST‐1). [ 160 ] Inheriting the structural attribute of SIM‐HKUST‐1, the derived hierarchically porous carbon (denoted as IM‐HPC, see Figure 15d) has shown smaller charge‐transfer resistance compared to that for microporous carbon (denoted as MPC, see Figure 15e) derived from conventional HKUST. As a result, IM‐HPC has harvested a considerably higher specific capacitance that for MPC across a wide current density (171–236 vs 75–128 F g −1 , see Figure 15f) and featured negligible capacitance retention after 10 000 cycles.…”

Three-dimensional ordered macroporous ZIF-8 nanoparticle-derived nitrogen-doped hierarchical porous carbons for high-performance lithium–sulfur batteries

“…2d) consisting of quadrates and hexagons, the microstructure of COM-ZIF-8 is composed of 6 square faces and 8 triangular faces, presenting the appearance of a cuboctahedron, as shown in Fig. 2b and c. In our previous work, 44 the effect of PS templates on MOF crystallization has been demonstrated. In brief, as shown in Fig.…”

Metal–Organic Frameworks and Their Derived Functional Materials for Supercapacitor Electrode Application

“…The pore architecture, SEM image, and high‐angle annular dark‐field scanning transmission electron microscopy (HAADF‐STEM) image of HKUST‐1 are separately shown in Figure 3b–d. [ 46 ] During the formation of HKUST‐1 from the PS template, sodium formate not only induces the nucleation of the crystallization solution through the deprotonation of ligands, but also serves as a capping agent to limit the crystal sizes. Moreover, the addition of a surfactant and second metal ions can also change the morphology of MOFs [38c,47] …”