Large-scale colloidal self-assembly by doctor blade coating.
TL;DR: A simple, roll-to-roll compatible coating technology for producing 3D highly ordered colloidal crystal-polymer nanocomposites, colloidal crystals, and macroporous polymer membranes and it is demonstrated that the doctor blade coating speed can be significantly increased by using a dual-blade setup.
Abstract: This article reports a simple, roll-to-roll compatible coating technology for producing 3D highly ordered colloidal crystal-polymer nanocomposites, colloidal crystals, and macroporous polymer membranes. A vertically beveled doctor blade is utilized to shear align silica microsphere-monomer suspensions to form large-area nanocomposites in a single step. The polymer matrix and the silica microspheres can be selectively removed to create colloidal crystals and self-standing macroporous polymer membranes. The thickness of the shear-aligned crystal is correlated with the viscosity of the colloidal suspension, and the coating speed and the correlations can be qualitatively explained by adapting the mechanisms developed for conventional doctor blade coating. We further demonstrate that the doctor blade coating speed can be significantly increased by using a dual-blade setup. The optical properties of the self-assembled structures are evaluated by normal-incidence reflection measurements, and the experimental results agree well with the theoretical predictions using Bragg's law and a scalar wave approximation model. We have also demonstrated that the templated macroporous polymers with interconnected voids and uniform interconnecting nanopores can be directly used as filtration membranes to achieve size-exclusive separation of particles.
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TL;DR: This work presents a new mesoporous composite material suitable for high-performance liquid chromatography and shows good chiral recognition ability and high uniformity in various racemates.
Abstract: Dingcai Wu,*,† Fei Xu,† Bin Sun,† Ruowen Fu,† Hongkun He,‡ and Krzysztof Matyjaszewski*,‡ †Materials Science Institute, Key Laboratory for Polymeric Composite and Functional Materials of Ministry of Education, School of Chemistry and Chemical Engineering, Sun Yat-sen University, Guangzhou 510275, People's Republic of China ‡Department of Chemistry, Carnegie Mellon University, 4400 Fifth Avenue, Pittsburgh, Pennsylvania 15213, United States
1,455 citations
TL;DR: This Review highlights the large number of methods to exploit colloidal assembly of comparably simple particles with nano- to micrometer dimensions in order to access complex structural hierarchies from nanoscopic over microscopic to macroscopic dimensions.
Abstract: This Review highlights the large number of methods to exploit colloidal assembly of comparably simple particles with nano- to micrometer dimensions in order to access complex structural hierarchies from nanoscopic over microscopic to macroscopic dimensions
609 citations
TL;DR: In this article, the authors describe the colloidal self-assembly of periodic and non-periodic photonic nanostructures in brief and then summarize recent achievements in the field of colloidal photonic nano-structures and their applications.
Abstract: Colloidal self-assembly has been investigated as a promising and practical approach for the fabrication of photonic nanostructures, including colloidal crystals, composite and inverse opals, and photonic glasses. Depending on the interactions between the colloidal particles, colloidal structures can be affected dramatically and modulated by applying an additional external field. Furthermore, in contrast to other approaches, self-assembled nanostructures with large areas or designed shapes can be prepared at low cost. As a result, the use of such colloidal systems has been investigated in many practical photonic applications. In this review article, we describe the colloidal self-assembly of periodic and non-periodic photonic nanostructures in brief and then summarize recent achievements in the field of colloidal photonic nanostructures and their applications, which include displays, optical devices, photochemistry and biological sensors.
354 citations
TL;DR: This critical review focuses on the solution deposition of transparent conductors with a particular focus on transparent conducting oxide (TCO) thin-films, with an introduction into the applications of and material criteria for TCOs.
Abstract: This critical review focuses on the solution deposition of transparent conductors with a particular focus on transparent conducting oxide (TCO) thin-films TCOs play a critical role in many current and emerging opto-electronic devices due to their unique combination of electronic conductivity and transparency in the visible region of the spectrum Atmospheric-pressure solution processing is an attractive alternative to conventional vacuum-based deposition methods due to its ease of fabrication, scalability, and potential to lower device manufacturing costs An introduction into the applications of and material criteria for TCOs will be presented first, followed by a discussion of solution routes to these systems Recent studies in the field will be reviewed according to their materials system Finally, the challenges and opportunities for further enabling research will be discussed in terms of emerging oxide systems and non-oxide based transparent conductors (341 references)
347 citations
TL;DR: This review gives a systematic, balanced and comprehensive summary of the main aspects of CCs related to their preparation and application, and proposes perspectives for the future developments ofCCs.
Abstract: Colloidal crystals (CCs) are ordered arrays of monodisperse colloidal particles. Because of the presence of a periodic superlattice of colloids and voids, CCs bear many unique structures and fascinating properties which are distinctly different from those of standard crystals with atoms, ions or molecules as repeating subunits. The research on CCs has surprisingly blossomed during recent decades, and many practical materials based on CCs with potential applications in photonic devices, material science and biomedical engineering have been generated. In this review, we give a systematic, balanced and comprehensive summary of the main aspects of CCs related to their preparation and application, and propose perspectives for the future developments of CCs.
187 citations