Unveiling the Potential of Redox Chemistry to Form Size-Tunable, High-Index Silicon Particles.

Silicon particles of intermediate sizes (75-200 nm) scatter visible wavelengths, making them promising candidates for optical devices. The solution synthesis of silicon particles in this size range, however, has proved challenging for chemists over the past few decades. Here, a solution-phase synthesis provides a pathway toward reaching size tunability between 45 and 230 nm via changing the reactant ratio in the reaction between a silicon Zintl phase (NaSi) with an amidinate-stabilized Si(IV) coordination complex.

Control over the spatial correlation of perforations in silica thin films as a function of solution conditions.

A perforated silica layer with structural correlation is engineered using sol-gel chemistry, applied to large-scale flat and curved surfaces. The anion(s) used in the preparation give tailored spatial correlation, and control over perforation size and density. Surface structuration is rapidly and reproducibly created using water and salts as inexpensive and ecofriendly reagents.

Size-tunable silicon nanoparticles synthesized in solution a redox reaction.

A current challenge in silicon chemistry is to perform liquid-phase synthesis of silicon nanoparticles, which would permit the use of colloidal synthesis techniques to control size and shape. Herein we show how silicon nanoparticles were synthesized at ambient temperature and pressure in organic solvents through a redox reaction. Specifically, a hexacoordinated silicon complex, bis(,'-diisopropylbutylamidinato)dichlorosilane, was reduced by a silicon Zintl phase, sodium silicide (NaSi).

Understanding the Formation Mechanisms of Silicon Particles from the Thermal Disproportionation of Hydrogen Silsesquioxane.

Crystalline silicon particles sustaining Mie resonances are readily obtained from the thermal processing of hydrogen silsesquioxane (HSQ). Here, the mechanisms involved in silicon particle formation and growth from HSQ are investigated through real-time analysis using an environmental transmission electron microscope and X-ray diffractometer. The nucleation of Si nanodomains is observed starting around 1000 °C.

Imaging Radial Distribution Functions of Complex Particles by Relayed Dynamic Nuclear Polarization.

The physical properties of many modern multi-component materials are determined by their internal microstructure. Tools capable of characterizing complex nanoscale architectures in composite materials are, therefore, essential to design materials with targeted properties. Depending on the morphology and the composition, structures may be measured by laser diffraction, scattering methods, or by electron microscopy.