Structural Diversity in Cryoaerogel Synthesis

Abstract

Different techniques that enable the selective microstructure design of aerogels without the use of additives are presented. For this, aerogels were prepared from platinum nanoparticle solutions using the cryoaerogelation method, and respective impacts of different freezing times, freezing media, and freezing temperatures were investigated with electron microscopy as well as inductively coupled plasma optical emission spectroscopy. The use of lower freezing temperatures, freezing media with higher heat conductivities, and longer freezing periods led to extremely different network structures with enhanced stability. In detail, materials were created in the shape of lamellar, cellular, and dendritic networks. So far, without changing the building blocks, it was not possible to create the selective morphologies of resulting aerogels in cryoaerogelation. Now, these additive-free approaches enable targeted structuring and will open up new opportunities in the future cryoaerogel design.

Interparticle Interaction Matters: Charge Carrier Dynamics in Hybrid Semiconductor–Metal Cryoaerogels

“…The highly porous nature of the coatings endows the systems with high accessible surface areas for interfacial reactions, which is a significant advantage over their simply drop‐cast nanoparticle film counterparts. [ 43,46,47 ]…”

Versatile Route for Multifunctional Aerogels Including Flaxseed Mucilage and Nanocrystals

“…Different mechanical, morphological, and structural properties of the obtained aerogels could be further modified/controlled by controlling wide range of freezing parameters such as freezing temperature, rate, and media. [ 9,59–61 ]…”

“…Different mechanical, morphological, and structural properties of the obtained aerogels could be further modified/controlled by controlling wide range of freezing parameters such as freezing temperature, rate, and media. [9,[59][60][61] ously reported for some aerogels of extremely low densities like cellulose nanofibers obtained aerogels. [56][57][58] The morphology and structure of the FSM-based aerogels were further investigated by SEM.…”

“…Cryogelation is an aerogelation technique recently developed, widely, and successively employed in our group to prepare different types of aerogels. [ 7–9 ] In the cryogelation technique, the solution or the gel of the corresponding building blocks is first frozen followed by freeze‐drying to obtain the final aerogel. The freeze drying not solely much easier to be performed compared to the supercritical CO 2 drying but it is widely available and employed in the industrial sector for diverse purposes and applications.…”

“…SEM images of the morphologies of the obtained aerogels of different flaxseed mucilage concentrations: g) 0.5%, h) 1.0%, i) 1.5% and j) 2.0% (w/V). Different mechanical, morphological, and structural properties of the obtained aerogels could be further modified/controlled by controlling wide range of freezing parameters such as freezing temperature, rate, and media [9,[59][60][61].…”