Elucidating the fundamental mechanisms of nanocrystal growth necessitates the utilization of high spatial resolution imaging techniques that are capable of directly imaging individual nucleation and growth events within a liquid phase. By combining time-resolved imaging datasets with quantitative image analysis algorithms, the factors controlling chemical transformations can be determined by an...

A quantitative understanding of nanocrystal phase transformations would enable more efficient energy conversion and catalysis, but has been hindered by difficulties in directly monitoring well-characterized nanoscale systems in reactive environments. We present a new in situ luminescence-based probe enabling direct quantification of nanocrystal phase transformations, applied here to the hydridi...

CoO nanocrystal/graphene nanosheets (GNS) composites, consisting of a triangular CoO nanocrystal of 2~20 nm on the surface of GNS, are synthesized by a mild synthetic method. First, cobalt acetate tetrahydrate is recrystallized in the alcohol solution at a low temperature. Then, graphene oxide mixed with cobalt-precursor followed by high vacuum annealing to form the CoO nanocrystal/GNS composit...

The photochemical instability of CdSe nanocrystals coated by hydrophilic thiols was studied nondestructively and systematically in water. The results revealed that the photochemical instability of the nanocrystals actually included three distinguishable processes, namely the photocatalytic oxidation of the thiol ligands on the surface of nanocrystals, the photooxidation of the nanocrystals, and...

Ordered gold nanocrystal/silica particles were synthesized through self-assembly of nanocrystal micelles and silicate. Depending on the use of surfactants, and the kinetic conditions of silica hydrolysis and condensation, well-shaped and irregularly-shaped silica particles were formed, inside which the nanocrystals self-organized in a face-centered cubic mesostructure.

The hydroisomerization of pure n-pentane over H-mordenite supported Pt-catalyst was investigated in a fixed bed reactor by changing reaction parameters such as temperature, pressure, and WHSV, as well as the H2/HC ratio. The maximum yield of isopentane over Pt/mordenite catalyst was achieved at 220 °C and a relatively low reaction pressure. To address the effect of feed composition on the catal...

Heck reactions were performed with 4-bromoacetophenone and n-butyl acrylate, yielding the trans-arylated acrylate ester with high selectivity. Pd–zeolite catalysts were compared with supported Pd metal catalysts. In order to obtain an active and heterogeneous catalyst, the preformed or in situ-formed catalytically active Pd0 species and the PdII intermediates must be sufficiently stabilized on ...

Periodic DFT calculations of the stability of mononuclear and oligonuclear Ga-oxo cations in mordenite (MOR) have been carried out. Independent of the aluminium distribution in the zeolite framework the stability of cyclic Ga(2)O(2)(2+) ions is much higher than that of the isolated GaO(+) (gallyl) ions in a high-silica mordenite (Si/Al = 23) model. As to the location of such dimers, favorable t...