A facile anisotropic surface modification and etching strategy is presented for the synthesis of hollow structured ZIF‐67 nanoframes. The strategy uses structural and compositional distinctions between each crystallographic facet of truncated rhombic dodecahedrons ZIF‐67 (tZIF‐67 RDs) and the moderate coordinating and etching effects of cyanuric acid (CA). The CA can anisotropically modify and protect the {110} facets from etching, causing the six {100} facets be selectively etched via an inside‐out manner, and finally forming the hollow nanoframes. The surface‐modified hollow tZIF‐67 RDs can be facet‐selectively etched by metal salts in an outside‐in manner to give metal‐doped tZIF‐67 nanoframes. After calcination, the metal‐tZIF‐67 hybrids are converted into metal‐Co alloy/C composite catalysts with hollow nanoframed structures. The PtCo/C catalyst with only 5.9 wt % Pt exhibits high catalytic activities and stabilities in the hydrogen evolution reaction (HER) in acidic solutions.

The application scope of metal−organic frameworks (MOFs) can be extended by rationally designing the architecture and components of MOFs, which can be achieved via a metal-containing solid templated strategy. However, this strategy suffers from low efficiency and provides only one specific MOF from one template. Herein, we present a versatile templated strategy in which organic ligands are weaved into hydrogen-bonded organic frameworks (HOFs) for the controllable and scalable synthesis of MOF nanotubes. HOF nanowires assembled from benzene-1,3,5-tricarboxylic acid and melamine via a simple sonochemical approach serve as both the template and precursor to produce MOF nanotubes with varied metal compositions. Hybrid nanotubes containing nanometal crystals and N-doped graphene prepared through a carbonization process show that the optimized NiRuIr alloy@NG nanotube exhibits excellent electrocatalytic HER activity and durability in alkaline media, outperforming most reported catalysts. The strategy proposed here demonstrates a pioneering study of combination of HOF and MOF, which shows great potential in the design of other nanosized MOFs with various architectures and compositions for potential applications.

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A facile anisotropic surface modification and etching strategy is presented for the synthesis of hollow structured ZIF‐67 nanoframes. The strategy uses structural and compositional distinctions between each crystallographic facet of truncated rhombic dodecahedrons ZIF‐67 (tZIF‐67 RDs) and the moderate coordinating and etching effects of cyanuric acid (CA). The CA can anisotropically modify and protect the {110} facets from etching, causing the six {100} facets be selectively etched via an inside‐out manner, and finally forming the hollow nanoframes. The surface‐modified hollow tZIF‐67 RDs can be facet‐selectively etched by metal salts in an outside‐in manner to give metal‐doped tZIF‐67 nanoframes. After calcination, the metal‐tZIF‐67 hybrids are converted into metal‐Co alloy/C composite catalysts with hollow nanoframed structures. The PtCo/C catalyst with only 5.9 wt % Pt exhibits high catalytic activities and stabilities in the hydrogen evolution reaction (HER) in acidic solutions.

No abstract