【作者】 黄璐；

【导师】 陈永胜；

【作者基本信息】 南开大学 ， 高分子化学与物理， 2013， 博士

【摘要】 1.喷墨打印氧化石墨烯导电墨水制备电子电路及电化学传感器。在这部分工作中,我们以单层氧化石墨烯(single-layered graphene oxide, GO)和寡层氧化石墨烯(few-layered graphene oxide, FGO)为原料,通过一系列简单的操作,制备出了基于石墨烯材料的导电墨水,并通过普通办公室喷墨打印机将该墨水打印到诸如纸张,聚对苯二甲酸乙二醇酯(poly(ethylene terephthalate), PET)和聚酰亚胺(polyimide, PI)等柔性基底上,然后通过简单的还原处理,得到了各种导电图案,图案的导电性在经过数百次弯折后,仍然保持不变,而且通过改变制备墨水所用的原料或重复打印的次数,可以可控的调节打印图案的导电性。基于这些研究,我们利用喷墨打印的方法,以氧化石墨烯为原料制备出了柔性的电子线路和柔性化学传感器。随后,我们用打印制备的电子线路与电池、LED组装成电子回路,在施加3V的电压时,LED发光,且当打印回路弯折时,LED亮度不变。同时,我们还用打印出的图形取代玻碳电极,在其表面负载上还原氧化石墨烯—二茂铁加和物制成化学传感器,在较低的电化学窗下实现了对双氧水的检测。这些结果证明了通过喷墨打印方法大规模制备基于石墨烯的电子器件的可行性,同时也为大规模制备诸如阵列式等精细石墨烯智能材料提供了指导作用。2.基于还原氧化石墨烯的自修复材料的研究。在这部分工作中,我们首先利用水合肼还原的还原氧化石墨烯(reduced graphene oxide, RGO)作为纳米添加剂,并选择广泛使用的热塑性聚氨酯(thermoplastic polyurethane, TPU)作为聚合物基体来制备自修复材料。由于1)石墨烯自身具有优异的力学性能；2)溶液还原法制备的RGO可在聚氨酯基体中均匀分散,3)还原后的氧化石墨烯因具有大的共轭n键,故对红外光以及电磁波有很强的吸收,因此聚氨酯基体材料在添加一定量的还原氧化石墨烯后,不仅力学性能得到提升,而且可以在红外光和电磁波的刺激作用下实现自修复,且能获得极好的修复性能。随后,我们进一步研究了氧化石墨烯的尺寸对材料自修复性能的影响,发现氧化石墨烯原料的尺寸越大,获得最佳修复效率时所需的红外光和电磁波刺激时间越短。这些研究结果为基于石墨烯的自修复智能材料提供了许多极为有用的信息,将对石墨烯基自修复材料的发展产生巨大影响。3.可多渠道重复修复的力学性能增强型寡层石墨烯(few-layered graphene, FG)—聚氨酯复合材料的自修复性能研究。在这部分工作中,我们直接采用大n共轭结构更为完整的电弧法合成的FG作为纳米添加剂,采用简单的溶液共混方法,将其均匀的添加到TPU基体中。由于FG与高分子材料相容性较好,且具有优异的力学性能,较高的导电性,同时对红外光、电磁波也有极佳的吸收能力,故而制备出的寡层石墨烯—热塑性聚氨酯(few-layered graphene□thermoplastic polyurethane, FG-TPU)复合材料相较于纯的TPU材料而言,不仅在力学性能上得到了较大的提高,同时可在红外光,电,电磁波的刺激作用下实现自修复,并能获得极好的修复效果,例如,在各种修复条件下,FG-TPU材料可反复的被修复,且每次修复效率均能高达98%及以上,此外,在各种修复条件下,FG-TPU材料均可在几分钟内被完全修复,在电修复条件下,更是可以在10s左右被完全修复。这些引人注目的结果预示着石墨烯基的自修复材料可被广泛的应用到各领域。更多还原

【Abstract】 1. Direct inkjet print graphene-based conducting inks to fabricate electrical circuits and chemical sensors. In this work, single-layered graphene oxide (GO) and few-layered graphene oxide (FGO) were used as raw materials, they were converted into graphene-based conducting inks after a series of simple processes. Then the graphene□based inks were printed on various flexible substrates including:commercial paper, poly(ethylene terephthalate)(PET) and polyimide (PI) via a office inkjet printer. After reduciton, the printed patterns became conductive and the conductivities of the patterns remained even after hundreds of bending cycles. We also can control the conductivities of the patterns by change the raw materials or the print times. Briefly, the conductivity of the pattern made from FGO is higher than that made from GO under the given print times, and with the print times increasing, the conductivity of the pattern increased when using the same raw material. Base on these results, we fabricated graphene-based electrical circuit and chemical sensor via simple inkjet printing. The circuit was composed of a3.0V battery, a printed graphene electronic pattern, and an LED. The brightness of the LED was identical, irrespective of whether the printed graphene electronic circuit was flat or bent. At the same time, we used the printed pattern to replace the glass carbon electrode, and then casted it with reduced graphene oxide-ferrocene adduct (RGO-Fc adduct) to fabricate a chemical sensor. This sensor can quickly observe the H2O2in the solution under a low electrical window. These results indicate that the method of inkjet printing not only can fabricate various graphene-based devices in large scale, but also can produce many kinds of graphene-based smart materials which have array structure in large scale.2. The study of the self-healing materials fabricated by reduced graphene oxide and thermoplastic polyurethane. In this work, we used the graphene oxide which had been reduced by hydrazine hydrate in solution as nano-additive, and then mixed it with the widely used thermoplastic polyurethane (TPU) matrix to fabricate the reduced graphene oxide-TPU composite (RGO-TPU composite). After adding some content of reduced graphene oxide (RGO), not only the mechanical strength of the conposites increased, but also the composites can be completely healed under the stimulation of infrared (IR) light and the electromagnetic wave. The reasons for these results are as follows:1) graphene materials always have excellent mechanical properties;2) the RGO synthesized by solution method can dispersed homogenously in the TPU matrix;3) the RGO can strongly absorbed the IR light and the electromagnetic wave because of its n conjugated structure. Furthermore, we also investigated the influence of the size of the added graphene oxide on the healing behavior, the results showed that with the size of graphene oxide sheets increasing, the time used to completely heal the composites decreased. This study offered some important information of the graphene-based self-healing materials, and will have an important effect on self-healig materials based on graphene.3. The investigation of multi-channel and repeatable self-healing of mechanical enhanced graphene-thermoplastic polyurethane composites. In this work, we chose the few-layered graphene (FG) synthesized via arc-discharge method as nano-additive, and then added it into the thermoplastic polyurethane (TPU) matrix through a simple solution mixing method. Because of the integrated π conjugated structure, the FG not only can mix with the TPU homogenously, but also possessed excellent mechanical property, the high electro and thermal conductivity, and the strong absorb capacity of IR light and electromagnetic wave. By adding some content of FG, the composites have an enhanced mechanical strength, and can be repeatedly healed by IR light, electricity and electromagnetic wave with excellent healing behaviors. For example:the FG-TPU composites can be repeatedly healed with healing efficiencies higher than98%under each of the three stimulations. Besides, all the FG-TPU composites can be completely healed under several minutes using the three methods. It can also be healed in10s under the electrical stimulation. The remarkable results indicated that our graphene based self-healing materials have a great potential to be used in various fileds.更多还原