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941.
Photonic Crystals: Template‐Directed Directionally Solidified 3D Mesostructured AgCl–KCl Eutectic Photonic Crystals (Adv. Mater. 31/2015) 下载免费PDF全文
942.
Metal‐Organic Frameworks: From Bimetallic Metal‐Organic Framework to Porous Carbon: High Surface Area and Multicomponent Active Dopants for Excellent Electrocatalysis (Adv. Mater. 34/2015) 下载免费PDF全文
943.
944.
Optoelectronics: High‐Performance Planar Perovskite Optoelectronic Devices: A Morphological and Interfacial Control by Polar Solvent Treatment (Adv. Mater. 23/2015) 下载免费PDF全文
945.
946.
Photoacoustic Imaging: In Situ Formation of Nanofibers from Purpurin18‐Peptide Conjugates and the Assembly Induced Retention Effect in Tumor Sites (Adv. Mater. 40/2015) 下载免费PDF全文
Di Zhang Guo‐Bin Qi Ying‐Xi Zhao Sheng‐Lin Qiao Chao Yang Hao Wang 《Advanced materials (Deerfield Beach, Fla.)》2015,27(40):6078-6078
947.
Widely Tunable Morphologies in Block Copolymer Thin Films Through Solvent Vapor Annealing Using Mixtures of Selective Solvents 下载免费PDF全文
Michelle A. Chavis Detlef‐M. Smilgies Ulrich B. Wiesner Christopher K. Ober 《Advanced functional materials》2015,25(20):3057-3065
Thin films of block copolymers are extremely attractive for nanofabrication because of their ability to form uniform and periodic nanoscale structures by microphase separation. One shortcoming of this approach is that to date the design of a desired equilibrium structure requires synthesis of a block copolymer de novo within the corresponding volume ratio of the blocks. In this work, solvent vapor annealing in supported thin films of poly(2‐hydroxyethyl methacrylate)‐block‐poly(methyl methacrylate) [PHEMA‐b‐PMMA] by means of grazing incidence small angle X‐ray scattering (GISAXS) is investigated. A spin‐coated thin film of a lamellar block copolymer is solvent vapor annealed to induce microphase separation and improve the long‐range order of the self‐assembled pattern. Annealing in a mixture of solvent vapors using a controlled volume ratio of solvents, which are chosen to be preferential for each block, enables selective formation of ordered lamellae, gyroid, hexagonal, or spherical morphologies from a single‐block copolymer with a fixed volume fraction. The selected microstructure is then kinetically trapped in the dry film by rapid drying. This paper describes what is thought to be the first reported case where in situ methods are used to study the transition of block copolymer films from one initial disordered morphology to four different ordered morphologies, covering much of the theoretical diblock copolymer phase diagram. 相似文献
948.
Yonggui Wang Lars‐Oliver Heim Yeping Xu Gerd Buntkowsky Kai Zhang 《Advanced functional materials》2015,25(9):1434-1441
The use of bio‐based nanoscaled cellulose for the construction of novel functional materials has progressed rapidly over the past years. In comparison to most of studies starting with the hydrophilic nanoscaled cellulose, surface‐stearoylated cellulose nanoparticles (SS‐CNPs) are used in this report for the construction of multifunctional, responsive films. SS‐CNPs with an average size of 115 ± 0.5 nm are obtained after the surface‐modification of cellulose under heterogeneous conditions. Crystalline cellulose core is present within SS‐CNPs according to solid‐state 13C nuclear magnetic resonance (NMR) spectroscopy. SS‐CNPs show excellent dispersibility in nonpolar solvents and form temperature‐responsive organogels in tetrahydrofuran (THF) at low temperature or after long time storage at room temperature. Moreover, transparent and self‐standing films of SS‐CNPs from their THF‐suspension show solvent‐responsive surface wettability and responsive shape‐memory property. SS‐CNPs can also be used for the fabrication of nanocomposite films together with nonpolar compounds, such as (2‐stearoylaminoethyl) rhodamine B. Thus, these novel SS‐CNPs derived from sustainable cellulose fibers are promising candidates for the construction of novel functional materials. 相似文献
949.
Materials and Wireless Microfluidic Systems for Electronics Capable of Chemical Dissolution on Demand 下载免费PDF全文
Chi Hwan Lee Jae‐Woong Jeong Yuhao Liu Yihui Zhang Yan Shi Seung‐Kyun Kang Jeonghyun Kim Jae Soon Kim Na Yeon Lee Bong Hoon Kim Kyung‐In Jang Lan Yin Min Ku Kim Anthony Banks Ungyu Paik Yonggang Huang John A. Rogers 《Advanced functional materials》2015,25(9):1338-1343
Electronics that are capable of destroying themselves, on demand and in a harmless way, might provide the ultimate form of data security. This paper presents materials and device architectures for triggered destruction of conventional microelectronic systems by means of microfluidic chemical etching of the constituent materials, including silicon, silicon dioxide, and metals (e.g., aluminum). Demonstrations in an array of home‐built metal‐oxide‐semiconductor field‐effect transistors that exploit ultrathin sheets of monocrystalline silicon and in radio‐frequency identification devices illustrate the utility of the approaches. 相似文献
950.
Efficiently Releasing the Trapped Energy Flow in White Organic Light‐Emitting Diodes with Multifunctional Nanofunnel Arrays 下载免费PDF全文
Lei Zhou Qing‐Dong Ou Yan‐Qing Li Heng‐Yang Xiang Lu‐Hai Xu Jing‐De Chen Chi Li Su Shen Shuit‐Tong Lee Jian‐Xin Tang 《Advanced functional materials》2015,25(18):2660-2668
White organic light‐emitting diodes (OLEDs) hold great promise for applications in displays and lighting due to high efficiency and superior white color balance. However, further improvement in efficiency remains a continuous and urgent demand due to limited energy flow extraction. A powerful method for drastically releasing the trapped energy flow in conventional white OLEDs is demonstrated by implementing unique quasi‐periodic subwavelength nanofunnel arrays (NFAs) via soft nanoimprinting lithography, which is ideal for enhancing light extraction without any spectral distortion or angular dependence. The resulting efficiency is over 2 times that of a conventional OLED used as a comparison. The external quantum efficiency and power efficiency are raised to 32.4% and 56.9 lm W?1, respectively. Besides, the substantial increase in efficiency over a broad bandwidth with angular color stability, the experimental proofs show that the NFA‐based extraction structure affords the enticing capacity against scrubbing and the self‐cleaning feature, which are critical to the commercial viability in practical applications. 相似文献