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A three‐dimensional (3D) hierarchical MOF‐on‐reduced graphene oxide (MOF‐on‐rGO) compartment was successfully synthesized through an in situ reduced and combined process. The unique properties of the MOF‐on‐rGO compartment combining the polarity and porous features of MOFs with the high conductivity of rGO make it an ideal candidate as a sulfur host in lithium–sulfur (Li‐S) batteries. A high initial discharge capacity of 1250 mAh g−1 at a current density of 0.1 C (1.0 C=1675 mAh g−1) was reached using the MOF‐on‐rGO based electrode. At the rate of 1.0 C, a high specific capacity of 601 mAh g−1 was still maintained after 400 discharge–charge cycles, which could be ascribed to the synergistic effect between MOFs and rGO. Both the hierarchical structures of rGO and the polar pore environment of MOF retard the diffusion and migration of soluble polysulfide, contributing to a stable cycling performance. Moreover, the spongy‐layered rGO can buffer the volume expansion and contraction changes, thus supplying stable structures for Li‐S batteries. [ABSTRACT FROM AUTHOR]

Abstract: We report a new method to promote the conductivities of metal–organic frameworks (MOFs) by 5 to 7 magnitudes, thus their potential in electrochemical applications can be fully revealed. This method combines the polarity and porosity advantages of MOFs with the conductive feature of conductive polymers, in this case, polypyrrole (ppy), to construct ppy‐MOF compartments for the confinement of sulfur in Li–S batteries. The performances of these ppy‐S‐in‐MOF electrodes exceed those of their MOF and ppy counterparts, especially at high charge–discharge rates. For the first time, the critical role of ion diffusion to the high rate performance was elucidated by comparing ppy‐MOF compartments with different pore geometries. The ppy‐S‐in‐PCN‐224 electrode with cross‐linked pores and tunnels stood out, with a high capacity of 670 and 440 mAh g−1 at 10.0 C after 200 and 1000 cycles, respectively, representing a new benchmark for long‐cycle performance at high rate in Li–S batteries. [ABSTRACT FROM AUTHOR]

[Display omitted] • Pd nanoparticles encapsulated in MOF-303 was designed and synthesized. • The adjacent pair of N atoms in MOF-303 facilitated the stabilization of Pd species. • The Pd nanoparticles exhibited excellent performance for HMF conversion to DHMTHF under mild conditions. • Pd in Pd@MOF-303 could expose more defective sites that were highly selective for the hydrogenation reaction. Catalytic conversion of biomass-derived compounds into value-added chemicals or liquid fuels is of significant importance for the valorization of sustainable biomass. Currently, selective hydrogenation of typical biomass-derived 5‑hydroxymethylfurfural (HMF) to the valuable 2,5-dihydroxymethyl-tetrahydrofuran (DHMTHF) has attracted considerable interest, but still suffers from the low efficiency and harsh H 2 pressure (usually 4 ∼ 8 MPa) in this process. Therefore, developing more efficient catalysts for the facile synthesis of DHMTHF from HMF under mild conditions is highly desired. Herein, small Pd nanoparticles were encapsulated in a metal–organic framework (Pd@MOF-303), and highly stabilized by the adjacent pair of N atoms of organic linkers of MOF-303. The small Pd nanoparticles were significantly efficient for HMF conversion to DHMTHF, and exhibited a yield of 95.8 % with a production rate of 85.1 h−1 under 1 MPa H 2. The excellent catalytic performance was attributed to the small Pd nanoparticles which could expose more stable defective sites that were highly active and selective for this reaction. [ABSTRACT FROM AUTHOR]

[Display omitted] • Single Cu atoms catalyst of Cu@UiO-66-(COOH) 2 was designed and synthesized. • High performance of LA hydrogenation to GVL was achieved via CTH route. • The defective sites in MOF facilitated the stabilization of Cu atoms. • The atomic dispersion of Cu and carboxyl group contributed to the high performance. Single-atom catalysts (SACs) have received great interests due to their high atomic utilization efficiency and unique electronic properties of active center atom. Here we reported a single-atom catalyst, Cu@UiO-66-(COOH) 2 , prepared by a simple, facile, and efficient solvothermal strategy, where Cu atoms were coordinated to the defect sites of secondary building units (SBUs) in a Zr-based metal–organic framework (MOF) UiO-66-(COOH) 2. The single-atom Cu@UiO-66-(COOH) 2 catalyst exhibited high activity for biomass derived platform chemical levulinic acid (LA) hydrogenation to γ-valerolactone (GVL) through catalytic transfer hydrogenation (CTH) process using isopropanol (IPA) as hydrogen donor under mild reaction conditions, where 96.7% GVL yield was achieved. The site isolation and uniform distribution of single Cu atoms combined with the aid of acid sites in MOF, attributing to the excellent catalytic performance for biomass upgrading. [ABSTRACT FROM AUTHOR]

3D assembled MOF-GH composite with high amphiphilic properties. • 3D porous hierarchical MOF-GH architectures were successfully synthesized. • The MIL-101-GH hybrid showed high affinity to both water and oils. • MIL-101-GH-TS-1 exhibited good heterogeneous catalytic performance toward 1-octene epoxidation.. Micro-nano surface with high-amphiphilic structures possesses fascinating physical properties and promising applications in many areas. Herein, we reported a three dimensional (3D) porous hierarchical architecture with internal crosslinked network structures constructed from metal-organic frameworks (MOFs) and graphene oxide (GO) through a facile self-assembly hydrothermal method. In contrast to conventional 3D graphene hydrogel with strongly hydrophobic structures, the resulting composite exhibited high-amphiphilic features with both highly hydrophilic and oleophilic ability, which could absorb water and oils simultaneously, owing to the synergistic effect between MOFs and reduced graphene oxide. MOFs acted as a dopant and intercalated between reduced graphene oxide layers, which could largely increase the specific surface areas of graphene hydrogels (GH) and artistically adjust the surface structures of pristine GH as well. Accordingly, the 3D porous hierarchical MIL-101-GH materials showed great absorption capacity for oil and water. The advantages of this high amphiphilic properties were proved by constructing a biphasic catalytic system with the introduction of molecular sieve into the 3D MIL-101-GH hybrid. As a result, the designing functionalized foam exhibited good catalytic performance in heterogeneous catalysis for epoxidation of olefins without addition of co-solvents. [ABSTRACT FROM AUTHOR]