Additive-Free Aqueous MXene Inks for Thermal Inkjet Printing on Textiles

Direct printing of functional inks onto flexible substrates allows for scalable fabrication of wearable electronics. However, existing ink formulations for inkjet printing require toxic solvents and additives, which make device fabrication more complex, limit substrate compatibility, and hinder device performance. Even water-based carbon or metal nanoparticle inks require supplemental surfactants, binders, and cosolvents to produce jettable colloidal suspensions. Here, a general approach is demonstrated for formulating conductive inkjet printable, additive-free aqueous Ti₃C₂T_x MXene inks for direct printing on various substrates. The rheological properties of the MXene inks are tuned by controlling the Ti₃C₂T_x flake size and concentration. Ti₃C₂T_x-based electrical conduits and microsupercapacitors (MSCs) are printed on textile and paper substrates by optimizing the nozzle geometry for high-resolution inkjet printing. The chemical stability and electrical properties of the printed devices are also studied after storing the devices for six months under ambient conditions. Current collector-free, textile-based MSCs show areal capacitance values up to 294 mF cm⁻² (2 mV s⁻¹) in poly(vinyl alcohol)/sulfuric acid gel electrolyte, surpassing reported printed MXene-based MSCs and inkjet-printed MSCs using other 2D nanomaterials. This work is an important step toward increasing the functional capacity of conductive inks and simplifying the fabrication of wearable textile-based electronics.     

Composite inks of poly(3,4-ethylenedioxythiophene)/poly(styrenesulfonate)/silver nanoparticles and electric/optical properties of inkjet-printed thin films

Poly(3,4-ethylenedioxythiophene)/poly(styrenesulfonate)/silver nanoparticles composite inks have been prepared through in situ synthesis and ultrasonic dispersion. The developed inks were proved to be suitable for various inkjet printing trials to deposit the thin films which were subsequently characterized to assess their electric and optical properties. The results have indicated that the dedoping of PSS from PEDOT during the in situ synthesis can be detrimental to the conductivity of the deposited composite films. However, the addition of silver nanoparticles to pristine PEDOT:PSS has significantly enhanced the conductivity of the thin films, with an inevitable loss in transparency. The various factors that can influence the properties of the thin films have also been analyzed and discussed. This study provides an insight into the effect of silver nanoparticles on PEDOT:PSS thin films deposited using inkjet printing process, and their properties due to the methods of ink formulation.     

Synthesis of silver nano particles and fabrication of aqueous Ag inks for inkjet printing

The main problem in preparing stable and printable inks containing nanoparticles for inkjet printing is to overcome the strong agglomeration of the particles in dispersion medium. In this study, the silver particles with diameter around 50 nm were produced by a simple wet chemistry method. Stable aqueous printable inks were formulated by using the combination of a triblock copolymer and high intensity focused ultrasound (HIFU). Various factors that affect the ink stability, such as, copolymer content and time of HIFU treatment, were investigated. The ink containing 5 wt% silver has a viscosity of about 2 mPa s and surface tension 30 mN m⁻¹ at 25 °C, which meet inkjet printer requirements. Such inks have been successfully printed on Al₂O₃ ceramics and low-temperature co-fired ceramics (LTCC) and the printed films show low resistivity.     

Film formation properties of inkjet printed poly(phenylene-ethynylene)-poly(phenylene-vinylene)s

Inkjet printing was used here as a precise and fast dispensing technique to prepare thin-film libraries of a poly-(phenylene-ethynylene)-poly(phenylene-vinylene)s copolymer. The films were prepared with a systematic variation of the ink composition, the dot spacing and the substrate temperature. Homogeneous films with a thickness of 100 nm were obtained when printed at room temperature and from a solvent mixture of toluene and ortho-dichlorobenzene in a volume ratio of 90/10. This approach can be used for optoelectronic applications, where the layer homogeneity is extremely important but where the ink compositions may vary per device, as well as the exact layer thickness. Our approach can be applied for the preparation of films by inkjet printing for any other (polymer) ink solution and represents a fast and efficient screening of the parameters to obtain homogeneous films with a precise thickness.     

Dewetting of conducting polymer inkjet droplets on patterned surfaces

The manufacture of high-performance electronic devices with micrometre or even submicrometre dimensions by solution processing and direct printing, requires the ability to control accurately the flow and spread of functional liquid inks on surfaces. This can be achieved with the help of surface-energy patterns causing inks to be repelled and dewetted from pre-defined regions of the substrate. To exploit this principle for the fabrication of submicrometre device structures, a detailed understanding of the factors causing ink droplets to dewet on patterned surfaces is required. Here, we use hydrophobic surface-energy barriers of different geometries to study the influence of solution viscosity, ink volume, and contact angle on the process of dewetting of inkjet-printed droplets of a water-based conducting polymer. We demonstrate polymer field-effect transistor devices with channel length of 500 nm fabricated by surface-energy-assisted inkjet printing.     

Low-Temperature Plasma Sintering of Inkjet-Printed Metal Salt Decomposition Inks on Flexible Substrates

Due to their complex formulation, conductive nanoparticle inks for inkjet printing are limited in terms of the types of metals and substrates that can be utilized. A new and simplified class of inks called metal salt decomposition (MSD) inks has the potential to introduce a multitude of metals, which can be printed directly onto a wide range of substrates. Here, the use of atmospheric oxygen plasma to develop polycrystalline Au and Pt films at processing temperatures near room temperature (≈33 °C) with excellent conductivities up to 10⁵ S m⁻¹ is demonstrated. The conformal nature of the ink allows metal films to be printed onto a broad range of temperature-sensitive substrates including polymers, papers, and fabric. The Au ink is then used to build a simple light-emitting diode circuit showing its flexibility, durability, and long-term stability as deposited thin metal films. Additionally, such inks cost less than one-third the price of similar nanoparticle inks highlighting their overall affordability and good stability.     

喷墨打印技术在功能材料精密器件加工中的应用

喷墨打印技术应用于聚合物成膜或成型,已成为功能聚合物沉积和精密器件加工领域的核心技术之一。介绍了喷墨打印技术在聚合物电致发光器件、有机薄膜晶体管、太阳能电池和传感器等领域的研究和应用进展,包括聚合物墨水的制备、薄膜均匀性、聚合物溶液与打印性能的关系、新型功能材料的研究和开发等问题,并指出了存在的问题和面临的挑战。     

Inkjet-printed microfluidic multianalyte chemical sensing paper

This paper presents an inkjet printing method for the fabrication of entire microfluidic multianalyte chemical sensing devices made from paper suitable for quantitative analysis, requiring only a single printing apparatus. An inkjet printing device is used for the fabrication of three-dimensional hydrophilic microfluidic patterns (550-mum-wide flow channels) and sensing areas (1.5 mm x 1.5 mm squares) on filter paper, by inkjet etching, and thereby locally dissolving a hydrophobic poly(styrene) layer obtained by soaking of the filter paper in a 1 wt % solution of poly(styrene) in toluene. In a second step, the same inkjet printing device is used to print "chemical sensing inks", comprising the necessary reagents for colorimetric analytical assays, into well-defined areas of the patterned microfluidic paper devices. The arrangement of the patterns, printed inks, and sensing areas was optimized to obtain homogeneous color responses. The results are "all-inkjet-printed" chemical sensing devices for the simultaneous determination of pH, total protein, and glucose in clinically relevant concentration ranges for urine analysis (0.46-46 muM for human serum albumin, 2.8-28.0 mM for glucose, and pH 5-9). Quantitative data are obtained by digital color analysis in the L*a*b* color space by means of a color scanner and a simple computer program.     

3D‐Printing Electrolytes for Solid‐State Batteries

Solid‐state batteries have many enticing advantages in terms of safety and stability, but the solid electrolytes upon which these batteries are based typically lead to high cell resistance. Both components of the resistance (interfacial, due to poor contact with electrolytes, and bulk, due to a thick electrolyte) are a result of the rudimentary manufacturing capabilities that exist for solid‐state electrolytes. In general, solid electrolytes are studied as flat pellets with planar interfaces, which minimizes interfacial contact area. Here, multiple ink formulations are developed that enable 3D printing of unique solid electrolyte microstructures with varying properties. These inks are used to 3D‐print a variety of patterns, which are then sintered to reveal thin, nonplanar, intricate architectures composed only of Li₇La₃Zr₂O₁₂ solid electrolyte. Using these 3D‐printing ink formulations to further study and optimize electrolyte structure could lead to solid‐state batteries with dramatically lower full cell resistance and higher energy and power density. In addition, the reported ink compositions could be used as a model recipe for other solid electrolyte or ceramic inks, perhaps enabling 3D printing in related fields.     

Reversible Conductive Inkjet Printing of Healable and Recyclable Electrodes on Cardboard and Paper

Conductive inkjet printing with metal nanoparticles is irreversible because the particles are sintered into a continuous metal film. The resulting structures are difficult to remove or repair and prone to cracking. Here, a hybrid ink is used to obviate the sintering step and print interconnected particle networks that become highly conductive immediately after drying. It is shown that reversible conductive printing is possible on low‐cost cardboard samples after applying standard paper industry coats that are adapted in terms of surface energy and porosity. The conductivity of the printed films approaches that of sintered standard inks on the same substrate, but the mobility of the hybrid particle film makes them less sensitive to cracks during bending and folding of the substrate. Damages that occur can be partially repaired by wetting the film such that particle mobility is increased and particles move to bridge insulating gaps in the film. It is demonstrated that the conductive material can be recovered from the cardboard at the end of its life time and be redispersed to recycle the particles and reuse them in conductive inks.     

导电油墨及其印刷技术的研究进展

目的 综述导电油墨及其印刷方式的研究进展,为开发价格低廉、性能稳定、导电性优良的导电油墨提供参考。方法 通过查阅文献归纳各类导电油墨的制备方式、印刷方式和应用领域,对导电油墨进行系统分类,比较各类导电油墨的性能和优缺点,并对其印刷技术进行分析,展望了导电油墨的发展前景。结果 目前关于导电油墨的研究集中在纳米银、纳米铜、石墨烯等导电填料的低温烧结油墨,主要采用丝网印刷、喷墨印刷等印刷方式,多用于制备传感器、柔性可穿戴设备等。未来的研究仍需关注如何低成本、低能耗、简单大量地制造导电油墨。结论 导电油墨的制备将与环境友好型的印刷方式相结合,向高导电性、高印刷适性发展,成为印刷电子领域的关键技术。     

Permanent magnetic thick films from remanence optimized NdFeB-inks

NdFeB films with thickness between 10 and 50 m are prepared by screen printing of standard inks containing 70–80 wt % of NdFeB powder (MQP-B). The coarse MQ-powder is fine-milled to give a mean particle size of about 10 m in order to obtain well-printable inks and homogeneous films. Typically, remanent inductions of 200–320 mT are obtained. The maximum loading of magnetic powder in the ink is increased to 85–90 wt % by optimizing the powder-particle packing. Mixtures of MQ-powders of different grain size were prepared in order to maximize the powders tap density and reduce the interparticle volume. Inks prepared from such powder mixtures display an increased remanence of up to 500 mT. Screen-printed NdFeB thick films are important components for miniature actuators or micro-electromechanical systems. In miniature systems the magnetic component has to provide a strong field without having a large size. Therefore, the reported enhancement of the remanence of NdFeB inks for screen printing of magnetic thick films represents dramatic progress compared to standard NdFeB inks.     

Large‐Area Organic Solar Cells: Material Requirements,Modular Designs,and Printing Methods

The printing of large‐area organic solar cells (OSCs) has become a frontier for organic electronics and is also regarded as a critical step in their industrial applications. With the rapid progress in the field of OSCs, the highest power conversion efficiency (PCE) for small‐area devices is approaching 15%, whereas the PCE for large‐area devices has also surpassed 10% in a single cell with an area of ≈1 cm². Here, the progress of this fast developing area is reviewed, mainly focusing on: 1) material requirements (materials that are able to form efficient thick active layer films for large‐area printing); 2) modular designs (effective designs that can suppress electrical, geometric, optical, and additional losses, leading to a reduction in the PCE of the devices, as a consequence of substrate area expansion); and 3) printing methods (various scalable fabrication techniques that are employed for large‐area fabrication, including knife coating, slot‐die coating, screen printing, inkjet printing, gravure printing, flexographic printing, pad printing, and brush coating). By combining thick‐film material systems with efficient modular designs exhibiting low‐efficiency losses and employing the right printing methods, the fabrication of large‐area OSCs will be successfully realized in the near future.     

国内计算机外设与耗材市场分析研究——彩色喷墨打印机及墨水的市场浅析

本文提供关于彩色喷墨打印器材的市场调研情况和分析。主要是关于彩色喷墨墨水方面，由于价格低廉，体积小，噪音低，色域广等优越的特性，2001年，我国彩色喷墨打印机的销售量已达1200万台，配套用的彩喷墨水市场需求量极大，目前，国内已有很多企业从事彩喷墨水的生产，已开发出一些价廉而质优的彩喷墨水产品，深受用户欢迎。     

LCD-based color filter films fabricated by a pigment-based colorant photo resist inks and printing technology

Inkjet printing technology has been applied to the fabrication of monochrome color filter films and has afforded an efficient and economic production process for flat panel displays. We demonstrate the preparation and physical characterization of the red and/or green monochrome films on glass substrates by inkjet printing technology with pigment-based colorant resist inks. For the green films, a thickness of 1.45 μm and the color coordinate value of x = 0.309, y = 0.588 and the brightness of Y = 58.90 in CIE 1931 diagram are attained at the optimal ink amounts of 1400 pl for green droplets. For the red colorant films, an appropriate film thickness of 1.20 μm and the coordinate value of x = 0.572, y = 0.320 and the brightness of Y = 27.1 in chromaticity diagram at the red droplets amounts of 900 pl are obtained. The experimental results exhibit the percentages of optical transmittance of the as-printed green films achieve greater than 85.0% in the spectral range of 515.0 nm and those of the as-printed red films in the subpixel cell can achieve 98.0% in the range of 640.0 nm.     

Elevated‐Temperature 3D Printing of Hybrid Solid‐State Electrolyte for Li‐Ion Batteries

While 3D printing of rechargeable batteries has received immense interest in advancing the next generation of 3D energy storage devices, challenges with the 3D printing of electrolytes still remain. Additional processing steps such as solvent evaporation were required for earlier studies of electrolyte fabrication, which hindered the simultaneous production of electrode and electrolyte in an all‐3D‐printed battery. Here, a novel method is demonstrated to fabricate hybrid solid‐state electrolytes using an elevated‐temperature direct ink writing technique without any additional processing steps. The hybrid solid‐state electrolyte consists of solid poly(vinylidene fluoride‐hexafluoropropylene) matrices and a Li⁺‐conducting ionic‐liquid electrolyte. The ink is modified by adding nanosized ceramic fillers to achieve the desired rheological properties. The ionic conductivity of the inks is 0.78 × 10 ^?3 S cm^?1. Interestingly, a continuous, thin, and dense layer is discovered to form between the porous electrolyte layer and the electrode, which effectively reduces the interfacial resistance of the solid‐state battery. Compared to the traditional methods of solid‐state battery assembly, the directly printed electrolyte helps to achieve higher capacities and a better rate performance. The direct fabrication of electrolyte from printable inks at an elevated temperature will shed new light on the design of all‐3D‐printed batteries for next‐generation electronic devices.     

Electromechanical properties of PZT/P(VDF-TrFE) composite ink printed on a flexible organic substrate

The fabrication and electromechanical properties of composite inks consisting of 30–70 vol.% of piezoceramic PZT powder and piezoelectric co-polymer P(VDF-TrFE) are presented. Samples were stencil-printed on a commercial PET film and printable silver ink was used for the electrodes thus allowing a maximum process temperature of 130 °C. The relative permittivity at 1 kHz varied between 33 and 69 depending on poling and composite composition. The highest remanent polarization, up to 4.8 μC/cm², with 34 MV/m electric field and piezoelectric coefficient d₃₁ up to 17 pm/V, was obtained with a 50 vol.% PZT loading level. The mechanical and electrical results indicate that the developed composite ink enables fully printable and flexible sensor applications with an increased level of integration.     

Nonpolar Solvent Modulated Inkjet Printing of Nanoparticle Self-Assembly Morphologies

Patterning of luminescent nanomaterials is critical in the fields of display and information encryption, and inkjet printing technology have shown remarkable significance with the advantage of fast, large-scalable and integrative. However, inkjet printing nanoparticle deposits with high-resolution and well controlled morphology from nonpolar solvent droplets is still challenging. Herein, a facile approach of nonpolar solvent modulated inkjet printing of nanoparticles self-assembly patterns driven by the shrinkage of the droplet and inner solutal convection is proposed. Through regulating the solvent composition and nanoparticle concentration, multicolor light-emissive upconversion nanoparticle self-assembly microarrays with tunable morphologies are achieved, showing the integration of designable microscale morphologies and photoluminescences for multimodal anti-counterfeit. Furthermore, inkjet printing of nanoparticles self-assembled continuous lines with adjustable morphologies by controlling the coalescence and drying of the ink droplets is achieved. The high resolution of inkjet printing microarrays and continuous lines’ width < 5 and 10 µm is realized, respectively. This nonpolar solvent-modulated inkjet printing of nanoparticle deposits approach facilitates the patterning and integration of different nanomaterials, and is expected to provide a versatile platform for fabricating advanced devices applied in photonics integration, micro-LED, and near-field display.     

用于喷墨打印的Ag2Se墨水的制备及表征

制备硒化银(Ag₂Se)薄膜材料对于组装微型器件至关重要, 目前大部分制备方法难以精确控制薄膜尺寸并进行图案化设计, 喷墨打印技术成为解决这一问题的有效方法, 实现其与Ag₂Se材料的组合具有重要意义。本工作通过溶剂热法制备了Ag₂Se纳米颗粒, 再与不同分散剂混合以筛选出适用于喷墨打印的稳定墨水, 进一步调节喷射参数以优化打印过程中墨滴的形态, 提高打印质量。将墨水打印至聚酰亚胺衬底上, 经热处理后制备得到Ag₂Se薄膜。使用不同手段对其物相与微结构进行表征, 并测试不同打印层数薄膜的电学性能。结果表明: 随着墨水固含量与打印层数增加, Ag₂Se薄膜的结晶度和致密度得到明显提升, 电导率也得到相应提高, 这主要源于薄膜内部Ag₂Se纳米颗粒沉积量与堆积密集程度增加。当使用固含量为5 mg·mL^-1的墨水进行打印, 打印层数为40层时, Ag₂Se薄膜的电导率达到399 S·cm^-1, 表现出较高的导电性能。本研究为制备Ag₂Se基薄膜材料与器件提供了新的方向。