Understanding of the major reactions in solution synthesis of functional nanomaterials

Photocatalysts with desirable selectivity to transformation and purification of targeted pollutants are of great importance in water purification. Here, we demonstrate that selective photocatalysis can be realized by the assistance of gold-enhanced selective adsorption onto carbon-coated Au/TiO2 mesoporous microspheres (Au/TiO2@C-MM), which were prepared via a surfactant-assisted two-step method that involved the assembly of oleic acid-stabilized titania and gold nanoparticles into colloidal spheres in an emulsion using sodium dodecyl sulfate as a surfactant and the conversion of the surfactants into carbon under annealing in Ar. Due to the negatively charged amorphous carbon, the mesoporous structure, and the surface plasmon resonance absorption of the Au components, the Au/TiO2@C-MM shows enhanced charge-and size-selective adsorption properties, which enables the materials to have high selectivity in the photocatalytic process.

Section: Selective Adsorption and Photodegradation Properties Of The mentioning

confidence: 50%

Carbon coated Au/TiO2 mesoporous microspheres: a novel selective photocatalyst

Liu

Wang

et al. 2017

“…High quality, large-area and single-layer MoS 2 can be fabricated by chemical vapor deposition (CVD) [5][6], but the grain boundary (GB) is inevitable and difficult to be identified. GBs affect the electron transfer process, and degrade the electrical and mechanical performances of MoS 2 , which limit the application of MoS 2 [7][8][9][10].…”

Section: Introductionmentioning

confidence: 99%

Optical visualization of MoS2 grain boundaries by gold deposition

Sun

Zheng

2018

The grain boundaries (GBs) in continuous films or domains of MoS 2 are vital to its optical and electrical properties. Almost all previous approaches for GBs visualization are based on microscopy and spectroscopy and only effective for domains with less than several micrometers in size. Here we report a simple method for the visualization of large GBs in MoS 2 surface by optical microscope. Gold was deposited on the MoS 2 grown by chemical vapor deposition, and then the GBs could be observed by optical microscope. Upon gold deposition on MoS 2 , the entire GBs of large-area MoS 2 were clearly visualized using this method. To verify the result, the GBs were also characterized via scanning electron microscopy, transmission electron microscopy and atomic force microscopy. It showed the small particles of gold were clustered together on GBs, which had a larger binding energy than the inner regions. The method is universal and allows for the nondestructive identification of the GBs in any two dimensional materials with large area.

“…Noble metal nanocrystals (NCs) have received increasing interest owing to their indispensable role in energy-related catalytic fields [1][2][3][4][5][6]. The scarce reserves and high cost of noble metals make it imperative to improve the atom utilization efficiencies and the performances of noble metal-based catalysts.…”

Section: Introductionmentioning

confidence: 99%

Synthesis of single-crystal hyperbranched rhodium nanoplates with remarkable catalytic properties

Zhang

Chen

et al. 2017

The catalytic properties of noble metal nanocrystals can be tuned via engineering their structures. Nanocrystals with fractal structures are fascinating catalysts regarding their large surface area-to-volume ratios, large numbers of edges and corners, which can be tuned simultaneously by their hierarchical ordering. However, it is still a great challenge to control the hierarchical ordering of noble metal fractal nanocrystals and their formation mechanism is not fully understood. Herein, we report a facile solvothermal method for the direct preparation of a unique single-crystal Rh-hyperbranched structure, which consists of hierarchically ultrathin nanoplates with threefold symmetry, large surface area and high density of low-coordinated edge/corner sites. Importantly, the hierarchical ordering can be readily tuned by changing the composition of solvent. In addition, we found the as-prepared single-crystal hyperbranched Rh nanoplates possessed great structure stability, and exhibited better catalytic performance towards both ethanol electrooxidation and hydrogenation of styrene than the commercial Rh black, which can be attributed to the large surface area and high-dentisty of edge/corner sites.