Journal ArticleDOI
Free-standing mesoporous silica films with tunable chiral nematic structures
TLDR
This work describes the development of a photonic mesoporous inorganic solid that is a cast of a chiral nematic liquid crystal formed from nanocrystalline cellulose, and is the first materials to combine mesoporosity with long-range chiral ordering that produces photonic properties.Abstract:
Chirality at the molecular level is found in diverse biological structures, such as polysaccharides, proteins and DNA, and is responsible for many of their unique properties. Introducing chirality into porous inorganic solids may produce new types of materials that could be useful for chiral separation, stereospecific catalysis, chiral recognition (sensing) and photonic materials. Template synthesis of inorganic solids using the self-assembly of lyotropic liquid crystals offers access to materials with well-defined porous structures, but only recently has chirality been introduced into hexagonal mesostructures through the use of a chiral surfactant. Efforts to impart chirality at a larger length scale using self-assembly are almost unknown. Here we describe the development of a photonic mesoporous inorganic solid that is a cast of a chiral nematic liquid crystal formed from nanocrystalline cellulose. These materials may be obtained as free-standing films with high surface area. The peak reflected wavelength of the films can be varied across the entire visible spectrum and into the near-infrared through simple changes in the synthetic conditions. To the best of our knowledge these are the first materials to combine mesoporosity with long-range chiral ordering that produces photonic properties. Our findings could lead to the development of new materials for applications in, for example, tuneable reflective filters and sensors. In addition, this type of material could be used as a hard template to generate other new materials with chiral nematic structures.read more
Citations
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Journal ArticleDOI
Key advances in the chemical modification of nanocelluloses
TL;DR: This review collocates current knowledge in the research and development of nanocelluloses and emphasizes more particularly on the chemical modification routes developed so far for their functionalization.
Journal ArticleDOI
Hierarchically porous carbon derived from polymers and biomass: effect of interconnected pores on energy applications
TL;DR: In this article, a review focusing on the out-of-the-box synthetic techniques capable of deriving hierarchical porous carbons (HPCs) with superior application profiles is presented.
Journal ArticleDOI
Wood-Derived Materials for Green Electronics, Biological Devices, and Energy Applications.
Hongli Zhu,Wei Luo,Peter N. Ciesielski,Zhiqiang Fang,Junyong Zhu,Gunnar Henriksson,Michael E. Himmel,Liangbing Hu +7 more
TL;DR: The goal of this study is to review the fundamental structures and chemistries of wood and wood-derived materials, which are essential for a wide range of existing and new enabling technologies.
Journal ArticleDOI
Sustainable carbon materials
Maria-Magdalena Titirici,Robin J. White,Nicolas Brun,Vitaliy L. Budarin,Dang Sheng Su,Francisco del Monte,James H. Clark,Mark J. MacLachlan +7 more
TL;DR: This review will introduce to the reader the most recent and important progress regarding the production of sustainable carbon materials, whilst also highlighting their application in important environmental and energy related fields.
Journal ArticleDOI
The evolution of 'sol-gel' chemistry as a technique for materials synthesis
TL;DR: In this article, the authors classify different types of sol-gel precursors and how these can influence a solgel process, from self-assembly and ordering in the initial solution, to phase separation during the gelation process and finally to crystallographic transformations at high temperature.
References
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Journal ArticleDOI
Ordered mesoporous molecular sieves synthesized by a liquid-crystal template mechanism
TL;DR: In this paper, the synthesis of mesoporous inorganic solids from calcination of aluminosilicate gels in the presence of surfactants is described, in which the silicate material forms inorganic walls between ordered surfactant micelles.
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Generalized syntheses of large-pore mesoporous metal oxides with semicrystalline frameworks
TL;DR: In this article, a simple and versatile procedure for the synthesis of thermally stable, ordered, large-pore (up to 140 A) mesoporous metal oxides was described.
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An ordered mesoporous organosilica hybrid material with a crystal-like wall structure.
TL;DR: The surfactant-mediated synthesis of an ordered benzene–silica hybrid material has an hexagonal array of mesopores and crystal-like pore walls that exhibit structural periodicity, and it is expected that other organosilicas and organo-metal oxides can be produced in a similar fashion, to yield a range of hierarchically ordered mesoporous solids with molecular-scale pore surface periodicity.
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Helicoidal self-ordering of cellulose microfibrils in aqueous suspension.
TL;DR: An in vitro system that attracts by its simplicity, where above a critical concentration the colloidal dispersion separates spontaneously into a chiral nematic liquid crystalline phase and solidifies into regularly twisted fibrillar layers that mimic the structural organization of helicoids in nature.
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Liquid-crystalline phases as templates for the synthesis of mesoporous silica
TL;DR: In this paper, the authors report the templating of silica mesostructures from ordered liquid-crystalline mesophases: the resulting silica phase, with pores of ∼3 nm diameter, is a cast of the organic mesophase.