3 years ago

Preparation of Mesoporous Basic Oxides through Assembly of Monodispersed Mg–Al Layered Double Hydroxide Nanoparticles

Preparation of Mesoporous Basic Oxides through Assembly of Monodispersed Mg–Al Layered Double Hydroxide Nanoparticles
Atsushi Shimojima, Hiroaki Wada, Takamichi Matsuno, Kazuyuki Kuroda, Yuya Oka, Keigo Kamata, Yoshiyuki Kuroda
Mesoporous basic Mg–Al mixed metal oxides (MMOs) with a high surface area and large pore size have been prepared through the assembly of monodispersed layered double hydroxide nanoparticles (LDHNPs) with block copolymer templates. The particle sizes of the LDHNPs were mainly controlled by varying the concentration of tris(hydroxymethyl)aminomethane (THAM), which was used as a surface stabilizing agent. LDHNPs and micelles of a block copolymer (Pluronic F127) were assembled to form a composite. The composites were calcined to transform them into mesoporous MMOs and to remove the templates. The Brunauer–Emmett–Teller surface areas, mesopore sizes, and pore volumes increased as a result of using the templates. Moreover, the pore sizes of the mesoporous MMOs could be controlled by using LDHNPs of different sizes. The mesoporous MMOs prepared from the LDHNPs showed much higher catalytic activity than a conventional MMO catalyst for the Knövenagel condensation of ethyl cyanoacetate with benzaldehyde. The mesoporous MMO catalyst prepared using the smallest LDHNPs, about 12 nm in size, showed the highest activity. Therefore, the use of monodispersed LDHNPs and templates is effective for preparing highly active mesoporous solid base catalysts. Controlled mesopore formation: Mesoporous Mg–Al mixed metal oxides (MMOs) with the highest surface area (ca. 400 m2 g−1) among reported MMOs have been prepared through the assembly of finely controlled layered double hydroxide nanoparticles and a block copolymer micelle followed by calcination (see graphic). The mesoporous MMOs showed very high catalytic activity for the Knövenagel condensation.

Publisher URL: http://onlinelibrary.wiley.com/resolve/doi

DOI: 10.1002/chem.201701282

You might also like
Discover & Discuss Important Research

Keeping up-to-date with research can feel impossible, with papers being published faster than you'll ever be able to read them. That's where Researcher comes in: we're simplifying discovery and making important discussions happen. With over 19,000 sources, including peer-reviewed journals, preprints, blogs, universities, podcasts and Live events across 10 research areas, you'll never miss what's important to you. It's like social media, but better. Oh, and we should mention - it's free.

  • Download from Google Play
  • Download from App Store
  • Download from AppInChina

Researcher displays publicly available abstracts and doesn’t host any full article content. If the content is open access, we will direct clicks from the abstracts to the publisher website and display the PDF copy on our platform. Clicks to view the full text will be directed to the publisher website, where only users with subscriptions or access through their institution are able to view the full article.