Catalytic ammonia reforming: alternative routes to net-zero-carbon hydrogen and fuel.

Ammonia is an energy-dense liquid hydrogen carrier and fuel whose accessible dissociation chemistries offer promising alternatives to hydrogen electrolysis, compression and dispensing at scale. Catalytic ammonia reforming has thus emerged as an area of renewed focus within the ammonia and hydrogen energy research & development communities. However, a majority of studies emphasize the discovery of new catalytic materials and their evaluation under idealized laboratory conditions.

Synthesis of Highly Accessible and Reactive Sites in Gold Nanoparticles Using Bound Bis(Diphenylphosphine) Ligands.

While bound organic ligands provide steric protection against aggregation for metallic nanoparticles in solution, they can block a large fraction of the surface atoms which are needed for binding in catalysis and sensing applications. In this work, highly accessible Au nanoparticles ligated with bis(diphenylphosphine) molecules are synthesized and characterized in solution. Characterization is performed using high angle annular dark field-scanning transmission electron microscopy (HAADF-STEM), ultraviolet-visible (UV-Vis) spectroscopy, and fluorescence chemisorption experiments.

Gold nanoparticles with tailored size through ligand modification for catalytic applications.

The active sites of catalysts can be tuned by using appropriate organic moieties. Here, we describe a facile approach to synthesise gold nanoparticles (AuNPs) using various Au(I) precursors. The core size of these AuNPs can be precisely tailored by varying the steric hindrance imposed by bound ligands.

Compensation Effect Exhibited by Gold Bimetallic Nanoparticles during CO Oxidation.

While CO oxidation catalyzed by gold nanoparticles has been practiced academically for several decades, there are still important discoveries to be made. One area of current interest is to pair Au with another alloying metal and observe the catalytic consequences of the presence of the other metal. In this work, TiO-supported bimetallic Au nanoparticles are alloyed with Cu, Co, Ni, Pd, and Ru and used as catalysts for CO oxidation.

Precisely Engineered Supported Gold Clusters as a Stable Catalyst for Propylene Epoxidation.

Designing a stable and selective catalyst with high H utilisation is of pivotal importance for the direct gas-phase epoxidation of propylene. This work describes a facile one-pot methodology to synthesise ligand-stabilised sub-nanometre gold clusters immobilised onto a zeolitic support (TS-1) to engineer a stable Au/TS-1 catalyst. A non-thermal O plasma technique is used for the quick removal of ligands with limited increase in particle size.

Plasmonic Photocatalytic Enhancement of L-Cysteine Self-Assembled Gold Nanoparticle Clusters for Fenton Reaction Catalysis.

Plasmon-enhanced photocatalysis has the potential to reduce activation energies and decrease temperature requirements, which increases catalyst stability and lowers process operating costs. The near-field enhancement that occurs at junctions between plasmonic nanoparticle clusters (i.e.

Mesostructure of Mesoporous Silica/Anodic Alumina Hierarchical Membranes Tuned with Ethanol.

Hierarchically structured membranes composed of mesoporous silica embedded inside the channels of anodic alumina (MS-AAM) were synthesized using the aspiration method. Ethanol is shown to have a significant effect on the type and organization of the mesoporous silica phase. Detailed textural analysis revealed that the pore size distribution of the mesoporous silica narrows and the degree of ordering increases with decreasing ethanol concentration used in the synthesis mixture.

Chaperonin-Inspired pH Protection by Mesoporous Silica SBA-15 on Myoglobin and Lysozyme.

While enzymes are valuable tools in many fields of biotechnology, they are fragile and must be protected against denaturing conditions such as unfavorable solution pH. Within living organisms, chaperonins help enzymes fold into their native shape and protect them from damage. Inspired by this natural solution, mesoporous silica SBA-15 with different pore diameters is synthesized as a support material for immobilizing and protecting enzymes.

Accessible gold clusters using calix[4]arene N-heterocyclic carbene and phosphine ligands.

We investigate the synthesis of accessible calix[4]arene-bound gold clusters consisting of open "coordinatively unsaturated" active sites, using a comparative approach that relies on calix[4]arene ligands with various upper- and lower-rim substituents. In contrast with a reported Au(I)-tert-butyl-calixarene phosphine complex, which exhibits a single cone conformer in solution, the H upper-rim analog exhibits multiple conformers in solution. This contrasts with observations of the tert-butyl upper-rim analog, which exhibits a single cone conformer in solution under similar conditions.

Delamination of layered zeolite precursors under mild conditions: synthesis of UCB-1 via fluoride/chloride anion-promoted exfoliation.

New material UCB-1 is synthesized via the delamination of zeolite precursor MCM-22 (P) at pH 9 using an aqueous solution of cetyltrimethylammonium bromide, tetrabutylammonium fluoride, and tetrabutylammonium chloride at 353 K. Characterization by powder X-ray diffraction, transmission electron microscopy, and nitrogen physisorption at 77 K indicates the same degree of delamination in UCB-1 as previously reported for delaminated zeolite precursors, which require a pH of greater than 13.5 and sonication in order to achieve exfoliation.

Synthesis of CdSe quantum dots with luminescence in the violet region of the solar spectrum.

We have designed a simple, one-step synthesis of CdSe quantum dots with photoluminescence frequencies ranging from the red through to the violet region of the solar spectrum. The photoluminescence peaks have FWHM of 30 nm indicating absorption over a narrow range of wavelengths. The effect of solvent type and solvent boiling point on the physical and photoluminescence properties of the quantum dots has been studied.