Photoisomerisation and ligand-controlled reversible aggregation of azobenzene-functionalised gold nanoparticles
作者:Anja Köhntopp、Alexandra Dabrowski、Michal Malicki、Friedrich Temps
DOI:10.1039/c4cc02250e
日期:——
The photochemical behaviour of functionalised gold nanoparticles (AuNPs) carrying azobenzenethiolate–alkylthiolate monolayers was investigated. Repeated trans–cis and cis–trans isomerisation cycles could be performed in all cases with high efficiency. Reversible photoinduced aggregation was observed when azothiolates with long alkyl spacers (≥C7) were combined with short (C5) alkylthiolate coligands. The choice of a coligand thus offers control over the aggregation properties of the nanoparticles.
Side-chain polysiloxane liquid crystalline elastomers from non-mesogenic components
作者:K. Mohana、S. Umadevi
DOI:10.1039/c9nj03482j
日期:——
a combination of differential scanning calorimetry, polarising optical microscopy and X-raydiffraction experiments. The X-raydiffractionstudies revealed an intercalated lamellar structure for the mesophase. Interestingly, the elastomer containing biphenyl-based cross-linker showed mesophase with an extended thermal range compared to the mesophase displayed by its counterpart containing phenyl-based
Metastable nanoparticle ink compositions and images made therefrom
申请人:Grzybowski Bartosz A.
公开号:US08496323B2
公开(公告)日:2013-07-30
Self-erasing inks in which both the printing and self-erasure of color images can be controlled by the dynamic/non-equilibrium aggregation of photoresponsive surface-coated nanoparticles contained in a carrier film are provided. The aggregation is a reversible aggregation that is triggered by a photo-induced transformation in ligands within the surface coating on the nanoparticles. Methods for forming images using the inks are also provided.
Dynamically Self-Assembling Carriers Enable Guiding of Diamagnetic Particles by Weak Magnets
作者:Olga Chovnik、Renata Balgley、Joel R. Goldman、Rafal Klajn
DOI:10.1021/ja309633v
日期:2012.12.5
We show that diamagnetic particles can be remotely manipulated by a magnet by the reversible adsorption of dual-responsive, light-switchable/superparamagnetic nanoparticles down to their surface. Adsorption occurs upon exposure to UV light, and can be reversed thermally or by ambient light. The dynamic self-assembly of thin films of the dual-responsive nanoparticles induces attractive interactions between diamagnetic particles. We demonstrate that catalytic amounts of the dual-responsive nanoparticles are sufficient to magnetically guide and deliver the diamagnetic particles to desired locations, where they can then be released by disassembling the dynamic layers of superparamagnetic nanoparticles with visible light.
Writing Self-Erasing Images using Metastable Nanoparticle “Inks”
作者:Rafal Klajn、Paul J. Wesson、Kyle J. M. Bishop、Bartosz A. Grzybowski
DOI:10.1002/anie.200901119
日期:2009.9.7
Mission Impossible: Metal nanoparticles (NPs) coated with photoresponsive ligands are used as “inks” for self‐erasing “paper” whereby light‐induced self‐assembly of the NPs is transduced into local color changes (see picture). Depending on the degree of self‐assembly, multicolor images can be written using only one type of NP ink. Duration of image erasure is regulated by the surface concentration