3D打印柔性可穿戴锂离子电池

利用挤出式3D打印技术制备纺织物结构的自支撑柔性锂离子电池电极的新方法,并采用高浓度的聚偏氟乙烯(PVDF)作为黏度调节剂、碳纳米管(CNT)作为导电剂、磷酸铁锂或钛酸锂作为电极活性材料,配制了具有可打印性的"墨水",其表观黏度接近105Pa·s,该"墨水"表现出明显的剪切变稀行为,同时存储模量平台值也高达105Pa,其优异的流变学性质对于打印和固化过程十分有利。电化学测试结果表明,两种打印电极具有稳定且十分匹配的充放电比容量,因此由二者组装的软包袋装全电池也具有高达~108mAh·g^-1的放电比容量(50mA·g^-1),弯曲后,在同样的电流密度下其放电比容量约为111mAh·g^-1。     

Fabrication of a 3D Nanoscale Crossbar Circuit by Nanotransfer‐Printing Lithography

Nanotransfer‐printing lithography simplifies the fabrication of a 3D nanoscale crossbar circuit. Gold nanowires 100 nm in width and with 100 nm spacing are printed onto a polymer layer of electrically switchable, LiClO₄‐doped poly[2‐methoxy‐5‐(2′‐ethylhexyloxy)‐p‐phenylene vinylene] mixed with an epoxy. The transfer process can be repeated to obtain a multilayer nanoscale crossbar structure. This process paves the way toward fabricating 3D circuits with ultrahigh device density and neuromorphic architectures.     

Surface‐Embedded Stretchable Electrodes by Direct Printing and their Uses to Fabricate Ultrathin Vibration Sensors and Circuits for 3D Structures

Printing is one of the easy and quick ways to make a stretchable wearable electronics. Conventional printing methods deposit conductive materials “on” or “inside” a rubber substrate. The conductors made by such printing methods cannot be used as device electrodes because of the large surface topology, poor stretchability, or weak adhesion between the substrate and the conducting material. Here, a method is presented by which conductive materials are printed in the way of being surface‐embedded in the rubber substrate; hence, the conductors can be widely used as device electrodes and circuits. The printing process involves a direct printing of a metal precursor solution in a block‐copolymer rubber substrate and chemical reduction of the precursor into metal nanoparticles. The electrical conductivity and sensitivity to the mechanical deformation can be controlled by adjusting the number of printing operations. The fabrication of highly sensitive vibration sensors is thus presented, which can detect weak pulses and sound waves. In addition, this work takes advantage of the viscoelasticity of the composite conductor to fabricate highly conductive stretchable circuits for complicated 3D structures. The printed electrodes are also used to fabricate a stretchable electrochemiluminescence display.     

高分子3D打印材料和打印工艺

3D打印技术亦称为增材制造,是基于三维数学模型数据,通过连续的物理层叠加,逐层增加材料来生成三维实体的技术。3D打印技术与传统材料加工技术相比有许多突出的优势,吸引了国内外工业界、投资界、学术界、新闻媒体和社会公众的热切关注。目前制约3D打印技术发展的因素主要有两个:打印工艺和打印材料。高分子聚合物在3D打印材料中占据主要地位。介绍了当前3D打印常用的高分子材料(热塑性高分子和光敏树脂)和与之相适应的打印工艺(FDM、SLS、SLA、Polyjet等),并对它们的特性和优缺点进行了评述,讨论了这些3D打印材料和工艺的开发面临的问题和挑战。     

Nanomaterial Patterning in 3D Printing

The synergistic integration of nanomaterials with 3D printing technologies can enable the creation of architecture and devices with an unprecedented level of functional integration. In particular, a multiscale 3D printing approach can seamlessly interweave nanomaterials with diverse classes of materials to impart, program, or modulate a wide range of functional properties in an otherwise passive 3D printed object. However, achieving such multiscale integration is challenging as it requires the ability to pattern, organize, or assemble nanomaterials in a 3D printing process. This review highlights the latest advances in the integration of nanomaterials with 3D printing, achieved by leveraging mechanical, electrical, magnetic, optical, or thermal phenomena. Ultimately, it is envisioned that such approaches can enable the creation of multifunctional constructs and devices that cannot be fabricated with conventional manufacturing approaches.     

Bukobot助力3D开源打印

开源运动帮助推进3D打印的便利性是最有影响力的。RepRap项目是大量低成本打印机配套元件的起源,包括现在相当著名的Makerbot。现在又有了一个新产品面市:Bukobot,开发人员将其描述为下一代的开源3D打印机。加州帕萨迪纳的Diego Porqueras,正定义他进入开放源码的3D打印机世界,需要解决的两个常见问题:易于使用、装配和可扩展性。Porqueras说,不像其他基于RepRap项目的很难组装的开源3D打印机,Bukobot(见以下视频)已经被设计为框架