No abstract

Quasi-MOFs'' realize both an open-framework structure and a strong interaction with the guest metal nanoparticles (NPs). Through controlled deligandation of metal-NP/MOF composites, metal-NP/quasi-MOF composites can be fabricated, leading to dramatically enhanced catalytic performance.

Micro-/nanocapsules have received substantial attention due to various potential applications for storage, catalysis, and drug delivery. However, their conventional enclosed non-/polycrystalline walls pose huge obstacles for rapid loading and mass diffusion. Here, we present a new single-crystal capsular-MOF with openings on the wall, which is carefully designed at the molecular level and constructed from a crystal-structure transformation. This rare open-capsule MOF can easily load the largest amounts of sulfur and iodine among known MOFs. In addition, derived from capsular-MOF and melamine through pyrolysis−phosphidation, we fabricated a nitrogen-doped capsular carbon-based framework with iron−nickel phosphide nanoparticles immobilized on capsular carbons interconnected by plentiful carbon nanotubes. Benefiting from synergistic effects between the carbon framework and highly surface-exposed phosphide sites, the material exhibits efficient multifunctional electrocatalysis for oxygen evolution, hydrogen evolution, and oxygen reduction, achieving well-qualified assemblies of an overall water splitting (low potential of 1.59 V at 10 mA•cm −2 ) and a rechargeable Zn−air battery (high peak power density of 250 mW•cm −2 and excellent stability for 500 h), which afford remarkably practical prospects over previously known electrocatalysts.

In this work, a hierarchically porous carbon was prepared from carbonization of a nitrogen-containing metal–organic framework, followed by activation under ultrasonication in aqueous potassium hydroxide (aq KOH). The activated carbon was applied as a support for immobilizing ultrafine palladium (Pd) nanoparticles (1.1 ± 0.2 nm). As a result, the as-prepared Pd nanoparticles on N-doped porous carbon with both micro- and mesoporosity exhibit an excellent activity for the dehydrogenation of formic acid, showing a high turnover frequency (TOF, 14 400 h–1) at 60 °C. This activation approach of carbon opens an avenue for the syntheses of highly active supported ultrafine metal NPs for catalysis.

Oxygen evolution reaction (OER) demands cost‐effective electrocatalysts with high catalytic performance. In this effort, metal–organic framework (MOF)‐derived nanocomposites are presenting promising prospects to achieve this goal. Herein, FeCo bimetallic MOFs with different compositions are prepared through a sodium hydroxide assisted approach. By means of a successive carbonization and phosphating reaction, a series of MOF‐derived multicomponent products are synthesized. The resultant P‐doped products present enhance electrocatalytic performance for OER in alkaline electrolyte in comparison with a commercial RuO2 catalyst, which paves the way for their practical applications for water splitting. The developed method herein also offers an opportunity for the large‐scale preparation of MOF‐derived product toward energy conversion applications.