Ultrafine Pt nanoparticles were successfully immobilized inside the pores of a metal-organic framework, MIL-101, without aggregation of Pt nanoparticles on the external surfaces of framework by using a "double solvents" method. TEM and electron tomographic measurements clearly demonstrated the uniform three-dimensional distribution of the ultrafine Pt NPs throughout the interior cavities of MIL-101. The resulting Pt@MIL-101 composites represent the first highly active MOF-immobilized metal nanocatalysts for catalytic reactions in all three phases: liquid-phase ammonia borane hydrolysis, solid-phase ammonia borane thermal dehydrogenation, and gas-phase CO oxidation.

Molecules that contain boron-boron multiple bonds are extremely rare due to the electron-deficient nature of boron. Here we report experimental and theoretical evidence of a neutral OCBBCO molecule with some boron-boron triple bond character. The molecule was produced and unambiguously characterized by matrix isolation infrared spectroscopy. Quantum chemical calculations indicate that the molecule has a linear singlet ground state with a very short boron-boron bond length.

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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.

In this work, we have developed a non-noble metal sacrificial approach for the first time to successfully immobilize highly dispersed AgPd nanoparticles on reduced graphene oxide (RGO). The Co3(BO3)2 co-precipitated with AgPd nanoparticles and subsequently sacrificed by acid etching effectively prevents the primary AgPd particles from aggregation. The resulted ultrafine AgPd nanoparticles exhibit the highest activity (turnover frequency, 2739 h(-1) at 323 K) among all the heterogeneous catalysts for the dehydrogenation of formic acid to generate hydrogen without CO impurity. The sacrificial approach opens up a new avenue for the development of high-performance metal nanocatalysts.

Ultrafine palladium nanoparticles (Pd NPs) supported on carbon nanospheres have been successfully synthesized using a facile methanol-mediated weakly-capping growth approach (WCGA) with anhydrous methanol as a mild reductant and a weakly capping agent. The Pd NPs show exceedingly high catalytic activity for 100% selective dehydrogenation of aqueous formic acid (FA) at ambient temperatures. The small size and clean surface of the Pd NPs greatly improve the catalytic properties of the as-prepared catalyst, providing an average rate of CO-free H2 generation up to 43 L H2 gPd(-1) min(-1) and a turnover frequency of 7256 h(-1) at 60 °C. These values are much higher than those obtained even with the most active catalyst reported thus far for heterogeneously catalyzed dehydrogenation of FA. This remarkably facile and effective methanol-mediated WCGA provides a powerful entry into ultrafine metal NPs with clean surface to achieve enhanced performance. Moreover, the catalytic results open up new avenues in the effective applications of FA for hydrogen storage.

Highly dispersed palladium nanoclusters (Pd NCs) immobilized by a nitrogen (N)-functionalized porous carbon support (N-MSC-30) are synthesized by a wet chemical reduction method, wherein the N-MSC-30 prepared by a tandem low-temperature heat-treatment approach proved to be a distinct support for stabilizing the Pd NCs. The prepared Pd/N-MSC-30 shows extremely high catalytic activity and recyclability for the dehydrogenation of formic acid (FA), affording the highest turnover frequency (TOF = 8414 h–1) at 333 K, which is much higher than that of the Pd catalyst supported on the N-MSC-30 prepared via a one-step process. This tandem heat-treatment strategy provides a facile and effective synthetic methodology to immobilize ultrafine metal NPs on N-functionalized carbon materials, which have tremendous application prospects in various catalytic fields.

An efficient strategy to downsize the metal nanoparticles (NPs) and provide basic sites located nearby for optimizing the catalytic performance of the reduced graphene oxide (rGO)-supported metal catalysts has been explored, for the first time, by the potent alkalization of rGO with diamine. By virtue of the coordination effects between the metal ions and the amine groups ligated to rGO, monodispersed Pd nanoparticles (diameter ≤ 1.5 nm) can be facilely anchored on the diamine-alkalized rGO by a simple reduction approach. The turnover frequency (TOF) for heterogeneously catalyzed decomposition of formic acid reaches 3810 h -1 at 323 K, the highest value ever reported under ambient conditions compared to the other heterogeneous catalysts.Supported metal nanoparticles (NPs), as a class of very promising nanocatalysts, have received great interest. Nevertheless, the syntheses of well-dispersed ultrafine metal NPs remain a great challenge. The structure and property of support materials are crucial for controlling the growth of metal NPs and thus improving the catalytic performance. 1 Reduced graphene oxide (rGO) consisting of chemically converted monolayer carbon atoms has emerged as one of the most promising supports for metal NPs because the unique advantage of hydrophilicity and large specific surface area of its precursor, graphene oxide (GO), makes it possible to anchor metal NPs in the solution-based controlled reduction. 2 However, due to its two-dimensional basal plane structure and the negligible interactions between GO and metals, it is still a major obstacle to obtain monodispersed metal particles with very small sizes on GO, where it is difficult to perfectly overcome the aggregation of NPs. 3 Rational modification of the GO surfaces with electron-rich functional groups would facilitate the dispersion of the metal precursors on the support and control the size during the growth of metal NPs. Moreover, such modification may also provide an opportunity to tailor the electronic properties and alkalinity/acidity of GO, and thus optimize the catalytic performance of the resultant catalysts. Nevertheless, a well-defined and controllable surface modification strategy of pristine GO is still lacking.Hydrogen is considered as a promising candidate for satisfying the increasing demand for the sustainable and clean energy supply. Formic acid (FA) has attracted tremendous research interest for hydrogen storage. 4 Recently, selective and efficient decomposition of FA has been achieved with homogeneous organometallic catalysts. 5 Compared to homogeneous catalysts, in general, heterogeneous catalysts are easily separated, controlled and recycled. 6 For practical application, the development of heterogeneous catalysts with high performance for hydrogen generation from FA is urgently desired. Herein, for the first time, we report the immobilization of ultrafine Pd NPs on diamine-alkalized reduced graphene oxide, PDA-rGO (PDA = 1,4-phenylenediamine), which exhibits the highest TOF value (3810 h -1 , 323 K), for FA decom...