Highly Luminescent Inks: Aggregation‐Induced Emission of Copper–Iodine Hybrid Clusters

Aggregation‐induced emission (AIE) is an attractive phenomenon in which materials display strong luminescence in the aggregated solid states rather than in the conventional dissolved molecular states. However, highly luminescent inks based on AIE are hard to be obtained because of the difficulty in finely controlling the crystallinity of AIE materials at nanoscale. Herein, we report the preparation of highly luminescent inks via oil‐in‐water microemulsion induced aggregation of Cu–I hybrid clusters based on the highly soluble copper iodide‐tris(3‐methylphenyl)phosphine (Cu₄I₄(P‐(m‐Tol)₃)₄) hybrid. Furthermore, we can synthesize a series of AIE inks with different light‐emission colors to cover the whole visible spectrum range via a facile ligand exchange processes. The assemblies of Cu–I hybrid clusters with AIE characteristics will pave the way to fabricate low‐cost highly luminescent inks.     

A novel highly flexible,simple, rapid and low-cost fabrication tool for paper-based microfluidic devices (μPADs) using technical drawing pens and in-house formulated aqueous inks

Paper-based microfluidic devices (μPADs) are capable of achieving rapid quantitative measurements of a variety of analytes inexpensively. μPADs rely on patterning hydrophilic-hydrophobic regions on a sheet of paper in order to create capillary channels within impermeable fluidic brakes on the paper. Here, we present a novel, highly flexible and low-cost fabrication method using a desktop digital craft plotter/cutter and technical drawing pens with tip size of 0.5 mm. The pens were used with either commercial black permanent ink for drawing fluidic brakes, or with specialty in-house formulated aqueous inks. With the permanent marker ink it was possible to create barriers on paper rapidly and in a variety of designs in a highly flexible manner. For instance, a design featuring eight reservoirs can be produced within 10 s for each μPAD with a consistent line width of brakes (%RSD < 1.5). Further, we investigated the optimal viscosity range of in-house formulated inks controlled with additions of poly(ethylene glycol). The viscosity was measured by capillary electrophoresis and the optimal viscosity was in the range of ∼3–6 mPa s. A functional test of these μPADs was conducted by the screening of antioxidant activity. Colorimetric measurements of flavonoid, phenolic compounds and DPPH free radical scavenging activity were carried out on μPADs. The results can be detected by the naked eye and simply quantified by using a camera phone and image analysis software. The fabrication method using technical drawing pens provides flexibility in the use of in-house formulated inks, short fabrication time, simplicity and low cost.     

Direct synthesis of self-assembled ferrite/carbon hybrid nanosheets for high performance lithium-ion battery anodes

Extensive applications of rechargeable lithium-ion batteries (LIBs) to various portable electronic devices and hybrid electric vehicles result in the increasing demand for the development of electrode materials with improved electrochemical performance including high energy, power density, and excellent cyclability, while maintaining low production cost. Here, we present a direct synthesis of ferrite/carbon hybrid nanosheets for high performance lithium-ion battery anodes. Uniform-sized ferrite nanocrystals and carbon materials were synthesized simultaneously through a single heating procedure using metal-oleate complex as the precursors for both ferrite and carbon. 2-D nanostructures were obtained by using sodium sulfate salt powder as a sacrificial template. The 2-D ferrite/carbon nanocomposites exhibited excellent cycling stability and rate performance derived from 2-D nanostructural characteristics. The synthetic procedure is simple, inexpensive, and scalable for mass production, and the highly ordered 2-D structure of these nanocomposites has great potential for many future applications.     

Positive microcontact printing with mercaptoalkyloligo(ethylene glycol)s

The soft lithographic replication of patterns with a low filling ratio by microcontact printing (microCP) is problematic due to the poor mechanical stability of common elastomeric stamps. A recently described strategy to avoid this problem employs a modified patterning method, positive microcontact printing ((+)microCP), in which a stamp with a mechanically more stable inverted relief pattern is used. In contrast to conventional negative microCP ((-)microCP), in the contact areas a self-assembled monolayer (SAM) is printed of a "positive ink", which provides only minor etch protection, whereas the noncontacted areas are subsequently covered with a different, etch-resistant SAM, prior to development by chemical etching. With the aim to identify novel, highly versatile positive inks, the patterning of gold by (+)microCP with mercaptoalkyloligo(ethylene glycol)s (MAOEGs), the subsequent adsorption of octadecanethiol (ODT), and the final development by wet chemical etching have now been studied. A polydisperse mixture of mercaptoundecylocta(ethylene glycol) derivatives was found to provide the best patterning results. The surface spreading of the positive ink during stamping, the exchange of printed MAOEGs with ODT, and the choice of the right etching bath were identified as key parameters that influence the achievable pattern resolution and contrast. Due to the modular composition of functionalized alkyloligo(ethylene glycol) derivatives, (+)microCP with these positive inks has the potential for easy adaptation to a variety of materials and development conditions.     

MODs vs. NPs: Vying for the Future of Printed Electronics

This Minireview compares two distinct ink types, namely metal-organic decomposition (MOD) and nanoparticle (NP) formulations, for use in the printing of some of the most conductive elements: silver, copper and aluminium. Printing of highly conductive features has found purpose across a broad array of electronics and as processing times and temperatures reduce, the avenues of application expand to low-cost flexible substrates, materials for wearable devices and beyond. Printing techniques such as screen, aerosol jet and inkjet printing are scalable, solution-based processes that historically have employed NP formulations to achieve low resistivity coatings printed at high resolution. Since the turn of the century, the rise in MOD inks has vastly extended the range of potentially applicable compounds that can be printed, whilst simultaneously addressing shelf life and sintering issues. A brief introduction to the field and requirements of an ink will be presented followed by a detailed discussion of a wide array of synthetic routes to both MOD and NP inks. Unindustrialized materials will be discussed, with the challenges and outlook considered for the market leaders: silver and copper, in comparison with the emerging field of aluminium inks.     

高分子功能材料图案化制备及其在光电领域的应用

基于半导体高分子功能材料的新型光电器件因其兼容性好、成本低、加工处理方便等特点逐渐走入人们的视野.加工集成高性能高分子光电器件需要用到可控图案化技术,这也将成为未来物联网、光通信、智能社会的基础核心技术.近年来,许多致力于此方面的研究取得了重要的成果.本文总结了各类高分子材料图案化技术,包括光刻法、模具诱导法、印刷法、浸润性调控组装法的技术特点,然后归纳了高分子图案化技术在场效应晶体管、光电探测器、气体传感器、电致发光二极管、光伏器件等光电器件领域的研究进展,最后对未来这一领域发展的挑战与机遇进行了展望.     

Microfluidic fabrication of complex-shaped microfibers by liquid template-aided multiphase microflow

This study presents a simple microfluidic approach to the rapid fabrication of complex-shaped microfibers (e.g., single hollow, double hollow, and microbelt), with highly uniform structures, based on a combination of the spontaneous formation of polymeric jet streams and in situ photopolymerization. Two laminar flows of a photocurable fluid and a liquid template (nonpolymerizing fluid) spontaneously form jet streams in equilibrium states in microfluidic channels because of the minimization of the interfacial energy between the two fluids. The formation of the jet streams strongly depends on the spreading coefficients and the evolution time along the downstream of the microfluidic system. Thus, the simple control of the spreading coefficients can guide microfibers into various shapes. The sizes of the core and shell of the hollow fibers can also be readily manipulated by the flow rates of the polymerizing fluid and the liquid template phase. Asymmetric hollow fibers can also be produced in different evolutionary states in the microfluidic system. The microfluidic approach shown here represents a significant step toward the easy fabrication of microfibers with readily controllable structures and geometries. We anticipate that this novel fabrication approach and the prediction method based on spreading coefficients presented in this work can be applied to produce a wide variety of functional microfibrous materials.     

Cell patterning using a template of microstructured organosilane layer fabricated by vacuum ultraviolet light lithography

Micropatterning techniques have become increasingly important in cellular biology. Cell patterning is achieved by various methods. Photolithography is one of the most popular methods, and several light sources (e.g., excimer lasers and mercury lamps) are used for that purpose. Vacuum ultraviolet (VUV) light that can be produced by an excimer lamp is advantageous for fabricating material patterns, since it can decompose organic materials directly and efficiently without photoresist or photosensitive materials. Despite the advantages, applications of VUV light to pattern biological materials are few. We have investigated cell patterning by using a template of a microstructured organosilane layer fabricated by VUV lithography. We first made a template of a microstructured organosilane layer by VUV lithography. Cell adhesive materials (poly(d-lysine) and polyethyleneimine) were chemically immobilized on the organosilane template, producing a cell adhesive material pattern. Primary rat cardiac and neuronal cells were successfully patterned by culturing them on the pattern substrate. Long-term culturing was attained for up to two weeks for cardiac cells and two months for cortex cells. We have discussed the reproducibility of cell patterning and made suggestions to improve it.     

One-step nanocasting synthesis of highly ordered single crystalline indium oxide nanowire arrays from mesostructured frameworks

A one-step nanocasting route has been demonstrated to prepare highly ordered single-crystal indium oxide nanowire (IONW) arrays with mesostructured frameworks. Unlike the reported multistep nanocasting process (synthesis of mesoporous materials, and then incorporation of precursors and formation of inorganic frameworks), a highly ordered mesostructured surfactant-silica monolith with low external surface serves as both the template and the reducing agent and makes the formation of single-crystal IONWs in its channels easily in one step by using normal In(NO(3))(3) as an inorganic precursor. After silica is removed, highly ordered uniform single-crystal IONW arrays with hexagonal (p6mm) or cubic (Ia3d) mesostructures are derived. These new materials are studied by XRD, SEM, TEM, N(2) adsoption, and UV spectrum. Furthermore, this one-step nanocasting synthesis route is a generalized method and can be used to synthesized a highly ordered mesoporous silica monolith with metal oxide nanocrystals in its channels. To the best of our knowledge, this is the first report of a single crystalline mesostructured In(2)O(3) framework.     

可用于印刷电子的水性CNTs导电材料及其在印刷电子器件上的应用

印刷电子技术较传统硅基微电子技术具有大面积、柔性化与低成本的优势,具有广阔的应用前景。而印刷电子材料的制备是印刷电子技术得以蓬勃发展的关键所在。碳纳米管（CNTs）是近年来发展迅速的新型碳材料之一,可应用在透明导电薄膜、晶体管、电容器、传感器、催化剂、高强度材料等各个材料领域。本文主要介绍了采用双亲共聚物改性CNTs,制备适用于印刷电子的导电墨水及其在印刷电子器件上的应用。     

Reactive silver inks for patterning high-conductivity features at mild temperatures

Reactive silver inks for printing highly conductive features (>10(4) S/cm) at room temperature have been created. These inks are stable, particle-free, and suitable for a wide range of patterning techniques. Upon annealing at 90 °C, the printed electrodes exhibit an electrical conductivity equivalent to that of bulk silver.     

Hydrophilic composite elastomeric mold for high-resolution soft lithography

Here, we introduce a nanopatternable hydrophilic composite elastomer highly desirable for both nanostructure patterning via solvent-assisted micromolding (SAMIM) and microcontact printing of polar inks. This composite precursor is prepared by blending two UV-curable materials, Norland Optical Adhesives (NOA) 63 and poly(ethylene glycol) diacrylate (PEGDA), in an appropriate ratio; upon UV polymerization, a nanopatternable elastomer with preferential permeability both to aqueous and organic solvent is fabricated. Using this composite mold, nanoscale SAMIM of poly(4-vinylpyridine) (P4VP) and microcontact printing of a polar biomolecule, bovine serum albumin (BSA), was successfully demonstrated, paving the way for facile and efficient reproduction of various nanopatterns and a biomolecule-printed array platform.     

胶体刻蚀——纳米结构化表面的构筑与应用

综述了近年来胶体刻蚀领域的研究进展, 分别讨论了基于胶体微粒和胶体晶体为模板的可控沉积与可控刻蚀及在固体平面基质、曲面基质和气液界面等不同基质上构筑结构化表面的方法. 同时还探讨了利用胶体刻蚀方法形成的微纳结构在光、电、磁以及表面润湿和生物学等方面的应用.     

生物蛋清蛋白模板合成海绵状大孔无机氧化物

多孔无机材料因可在微加工,催化,生物分离,电子器件的矿化和色谱载体等方面的广泛应用而引起人们极大的兴趣^[1-9],模板技术是制备孔材料最有效的工具之一,以表面活性剂和嵌段共聚物作为模板剂可以合成出结构多样,孔径均一,有序度高的介孔分子筛（2－50nm),大孔无机材料（＞50nm)通常采用以高分子微球和微乳液作模板的方法来合成（^[10],最近,我们利用浓度极高的;盐溶液和聚苯乙烯球作为模板,合成了3D海绵状大孔和介孔复合的氧化硅薄片^[11][,利用电化学等方法合成了具有特殊光阻性质的大孔氧化硅,氧化钛,金属以及合金材料等^[12],利用电化学等方法合成了具有特殊光阻性质的大孔氧化硅,氧化钛,金属以及合成材料等^[12],也有人利用相分离的方法制备无序大孔材料,但该方法一般较复杂,成本也比较昂贵,自然界中的大孔材料如海藻,珊瑚（氧化硅）是通过生物蛋白质为模板在基胞核内形成的,但是生物蛋白的模板作用和形成机理目前还不十分清楚。     

Template synthesis of ordered macroporous hydroxyapatite bioceramics

Hydroxyapatite has found wide application in bone tissue engineering. Here we use a macroporous carbon template to generate highly ordered macroporous hydroxyapatite bioceramics composed of close-packed hollow spherical pores with interconnected channels. The template has advantages for the preparation of ordered materials.     

Single‐Step Synthesis of Mesoporous Carbon Nitride/Molybdenum Sulfide Nanohybrids for High‐Performance Sodium‐Ion Batteries

Molybdenum disulfide (MoS₂) is a promising candidate as a high‐performing anode material for sodium‐ion batteries (SIBs) due to its large interlayer spacing. However, it suffers from continued capacity fading. This problem could be overcome by hybridizing MoS₂ with nanostructured carbon‐based materials, but it is quite challenging. Herein, we demonstrate a single‐step strategy for the preparation of MoS₂ coupled with ordered mesoporous carbon nitride using a nanotemplating approach which involves the pyrolysis of phosphomolybdic acid hydrate (PMA), dithiooxamide (DTO) and 5‐amino‐1H‐tetrazole (5‐ATTZ) together in the porous channels of 3D mesoporous silica template. The sulfidation to MoS₂, polymerization to carbon nitride (CN) and their hybridization occur simultaneously within a mesoporous silica template during a calcination process. The CN/MoS₂ hybrid prepared by this unique approach is highly pure and exhibits good crystallinity as well as delivers excellent performance for SIBs with specific capacities of 605 and 431 mAhg^?1 at current densities of 100 and 1000 mAg^?1, respectively, for SIBs.     

Chemical composition of contemporary black printing inks based on infrared spectroscopy: basic information for the characterization and discrimination of artistic prints

This article aims to provide the basic information necessary to afford the discrimination of artistic prints based on chemical information. The presence of original and non-original prints in the art market is a real problem, especially for contemporary artists. Most of the non-original elements can be distinguished on the basis of their stylistics and printing characteristics, but sometimes this information is not enough. To facilitate discrimination in these cases, we propose to add, to the previously indicated aspects, the chemical information of the materials involved in the production of the original series (inks, paper and pencil). Comparison of the composition of any element with that established for the original series will permit the attribution of any doubtful element. This article is focused on the evaluation of this approach by determining the chemical composition of contemporary black printing inks by infrared spectroscopy and by searching, on the basis of the information obtained, for criteria capable to discriminate between prints made of different inks. The success of the approach with this set of inks could easily be extended to the study of colour inks. The study also includes the characterization and discrimination of black pigments because they are the most characteristic component of these inks and because this information can also be useful for other artistic studies. The procedure proposed permits the analysis of inks with minimum deterioration of the artwork. Results indicate the capability of the approach because, following the procedure, it is possible to distinguish between black pigments attending to the presence of hydroxyapatite, silicate and some other specific bands, whereas black inks can be discriminated by paying attention to the inclusion in their composition of such pigments as bone black, Prussian blue, mars brown or other specific bands. Scanning electron microscopy analyses have corroborated the results obtained.     

印刷电子用金属材料的墨水化及图案化研究进展

印刷电子是采用印刷工艺,把功能性墨水快速印制在有机或无机基材上,形成各种电子元件和线路的科学与技术。其中墨水的制备,即各种功能材料的墨水化,以及后续在软基材上的印刷成膜,即墨水的图案化,是决定印刷电子实用化发展的关键。本文主要介绍了金属材料的墨水制备及其印刷烧结技术的研究进展,讨论了印制电子带来的材料和技术的挑战及机遇,指出导电材料选择及其墨水化与图案化有机结合是未来印刷电子和材料发展的方向。     

Micropatterning of organic semiconductor microcrystalline materials and OFET fabrication by "hot lift off"

Considerable progress toward the development of electronic devices that rely on organic semiconductors as the active material component has been made in recent years. The key step for realization of the advanced organic electronic, or optical, device is the ability to micropattern different kinds of electronic materials, such as organic semiconductor/conducting materials, over large areas with micrometer-sized resolution. Here we demonstrate a simple and direct method for micropatterning small-molecule microcrystalline films using an epoxy stamp. The "hot lift off" method is highly selective, creating patterns with high resolution and relies on straightforwardly tailoring the adhesive properties between the epoxy and the film. This process is well suited for patterning many types of materials.     

Disposable electrochemical paper-based devices fully fabricated by screen-printing technique

This work presents a novel method for the full fabrication of electrochemical paper-based cells by screen-printing technology. Firstly, a mixture of ultraviolet curable inks was used for patterning hydrophobic barriers into chromatography paper. Afterwards three-electrode systems were coupled for electrochemical detection by printing successively carbon and silver/silver chloride inks over the hydrophilic areas. The resulting electrochemical cells were characterized by cyclic voltammetry in different redox systems and used for amperometric detection of ferricyanide.