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The article cites a study by researcher R.V. Jagadeesh et al. on the general synthesis of amines through reductive amination of carbonyl compounds. The researchers use a cobalt nanoparticle catalyst with a structure derived from the pyrolysis of a metal-organic framework (MOF) compound. The catalysts are vital because of their high activities and selectivities.

The article presents a study which examines the synergic effect of rhodium (Rh) and nickel (Ni) in Rh-Ni alloy nanoparticles (NPs) on the hydrogen selectivity of Rh NPs. It uses bimetallic Rh-Ni nanocatalysts which were generated as black suspension through a surfactant aided coreduction process. It concludes that alloying Rh and Ni in the bimetallic Rh4Ni nanocatalyst at room temperature can achieve 100% conversion of hydrous hydrazine to hydrogen.

Meso-/macropores have been induced as additional second-order structures by the assembly of particles of a microporous zeolitic imidazolate framework, ZIF-8, prepared by ultrasonication. Simple carbonization of ZIF-8 affords a 3-dimensional hierarchically porous carbon framework with micro-, meso- and macropores, which exhibits the best performance ever reported as a supercapacitor electrode. [ABSTRACT FROM AUTHOR]

Antibodies blocking the PD-1/PD-L1 pathway have achieved great success. However, some disadvantages of antibodies have been found, which limit their clinical applications. Peptide antagonists are alternatives to antibodies in PD-1/PD-L1 blockage, but successful studies in this area are limited. A PD-1 targeting peptide, P-F4, was identified using phage display. P-F4 bound PD-1 with an affinity of 0.119 μM, inhibited PD-1/PD-L1 interaction at the cellular level and modulated T cell activity in vitro. We have overcome the poor solubility and rapid degradation problems of this peptide by packaging P-F4 in nanoparticles. In vivo experiments demonstrated that P-F4 nanoparticles could strongly inhibit tumor growth in a CT26 mouse model. Further research revealed that treatment of P-F4 nanoparticles increased CD8+T cells and reduced Tregs in the tumor microenvironment and tumor-draining lymph nodes. It was shown that treatment of P-F4 nanoparticles also increased lymphocytic activities, including proliferation, cytokine secretion and cytolytic activity. Moreover, computer modeling suggested that the P-F4 binding site to PD-1 overlaps with the PD-L1 binding surface. In this study, a peptide candidate for cancer immunotherapy was provided, and its working mechanisms were studied. [ABSTRACT FROM AUTHOR]

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. [ABSTRACT FROM AUTHOR]

Few layers graphene nanosheets (GS) are obtained by the reduction of graphite oxide (GO) via Lithium aluminium tetrahydride (LiAlH4) and Phosphorus tribromide (PBr3) as the deoxidizer. The LiFePO4/GS composite is prepared using a solution phase method followed by a calcination process with only 2 h at 600 °C. The effect of the GS content in LiFePO4/GS on the morphology and electrochemical performance of LiFePO4 particles is extensively investigated. Results show that the optimized amount of GS in LiFePO4/GS is 5%. The primary particle size of LiFePO4/5%GS is 100~150 nm which are wrapped and connected homogeneously and loosely by GS with ~4 layers. The GS can restrict the growth of LiFePO4particle and construct an effective conductive network LiFePO4/GS composite, which all can enhance the conductivity of LiFePO4 particle. The LiFePO4/5%GS composite delivers a capacity of 155.4 mAhg-1 at 0.2 C, which is much higher than pure LiFePO4 (125.3 mAhg-1). Even at high rate of 5 C, a specific capacity of 124.3 mAhg-1 is achievable, with no obvious capacity fading after 100 cycles. [ABSTRACT FROM AUTHOR]

For the first time, this work presents surfactant-free monometallic and bimetallic polyhedral metal nanocrystals (MNCs) immobilized to a metal–organic framework (MIL-101) by CO-directed reduction of metal precursors at the solid–gas interface. With this novel method, Pt cubes and Pd tetrahedra were formed by CO preferential bindings on their (100) and (111) facets, respectively. PtPd bimetallic nanocrystals showed metal segregation, leading to Pd-rich core and Pt-rich shell. Core–shell Pt@Pd nanocrystals were immobilized to MIL-101 by seed-mediated two-step reduction, representing the first example of core–shell MNCs formed using only gas-phase reducing agents. These MOF-supported MNCs exhibited high catalytic activities for CO oxidation. [ABSTRACT FROM AUTHOR]

Bimetallic Au-Pd nanoparticles (NPs) were successfully immobilized in the metal-organic frameworks (MOFs) MIL-101 and ethylenediamine (ED)-grafted MIL-101 (ED-MIL-101) using a simple liquid impregnation method. The resulting composites, Au-Pd/MIL-101 and Au-Pd/ED-MIL-101, represent the first highly active MOF-immobilized metal catalysts for the complete conversion of formic acid to high-quality hydrogen at a convenient temperature for chemical hydrogen storage. Au-Pd NPs with strong bimetallic synergistic effects have a much higher catalytic activity and a higher tolerance with respect to CO poisoning than monometallic Au and Pd counterparts. [ABSTRACT FROM AUTHOR]

In this paper, two kinds of Ni nanoparticles have been successfully synthesized without and with starch as the "green" protective material and investigated as catalysts for generating hydrogen from ammonia borane (NH3BH3, AB). Experimental investigations have demonstrated that both of the Ni nanoparticles possess high activities fo H2 generation from aqueous solution of AB. However, the catalytic activities of Ni nanoparticles without starch decrease seriously in the course of the lifetime tests. In contrast, the catalytic activities of the Ni nanoparticles with starch almost keep unchanged even after 240 h. Moreover, the XPS results show that the surface of the Ni nanoparticles in starch solution is still metallic Ni even after 240 h, while that in pure water is nickel oxide. This means that starch can successfully keep the Ni nanoparticles in aqueous solution from the oxidation in air. The present efficient, low-cost, and longtime water/air stable Ni catalyst represents a promising step toward the development of AB as a viable on-board hydrogen storage and supply material. [ABSTRACT FROM AUTHOR]

For the first time, this work presents Au@Ag core-shell nanoparticles (NPs) immobilized on a metal-organic framework (MOF) by a sequential deposition-reduction method. The small-size Au@Ag NPs reveal the restriction effects of the pore/surface structure in the MOF. The modulation of the Au/Ag ratio can tune the composition and a reversed Au/Ag deposition sequence changes the structure of Au-Ag NPs, while a posttreatment process transforms the core-shell NPs to a AuAg alloy. Catalytic studies show a strong bimetallic synergistic effect of core shell structured Au@Ag NPs, which have much higher catalytic activities than alloy and monometallic NPs. [ABSTRACT FROM AUTHOR]

The article discusses the methodology for the synthesis of Gold@Cobalt (Au@Co) magnetic core-shell structured nanoparticles (NPs) through a one-step seeding growth method at room temperature under ambient atmosphere. It mentions that the resultant of the Au@Co NPs present a high catalytic activity and long-term stability for the hydrolytic dehydrogeneration of aqueous AB. It notes that the rational and general method can be easily extended other metallic systems.

The article discusses the application of a zeolite-type metal-organic framework (MOF) in assisting the preparation of nanoparticulate gold catalysts for the gas phase carbon monoxide (CO) oxidation. It notes that the results from a simple solid grinding method are likely to bring new opportunities in the enhancement of high-performance gold catalysts. Furthermore, the pores' tunable size and shape indicate a great potential as candidates for novel heterogenous catalysts.