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Laser-Assisted Multiscale Fabrication of Configuration-Editable Supercapacitors with High Energy Density Jian Gao,† Changxiang Shao,† Shengxian Shao,† Congcong Bai,† Ur Rehman Khalil,† Yang Zhao,*,† Lan Jiang,‡ and Liangti Qu*,†,§ Downloaded via GUILFORD COLG on July 24, 2019 at 01:51:17 (UTC). See https://pubs.acs.org/sharingguidelines for options on how to legitimately share published articles.
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Key Laboratory of Photoelectronic/Eletrophotonic Conversion Materials, School of Chemistry, Beijing Institute of Technology, Beijing 100081, P.R. China ‡ Laser Micro-/Nano-Fabrication Laboratory, School of Mechanical Engineering, Beijing Institute of Technology, Beijing 100081, P.R. China § Key Laboratory for Advanced Materials Processing Technology, Ministry of Education of China, State Key Laboratory of Tribology, Department of Mechanical Engineering, Tsinghua University, Beijing 100084, P.R. China S Supporting Information *
ABSTRACT: The construction of multidimensional, diversified microsupercapacitors (MSC) is urgently needed for fast-changing flexible and wearable microelectronics, which still meets the challenges of tedious construction and difficult integration. Herein, a laser direct writing strategy has been developed for the one-step preparation of multiscale MSCs from editable macro-supercapacitors. The microstructured supercapacitors with predefined multiscale shapes not only maintain the high capacitance performance and stability but also display the tensile properties in arbitrary direction. The heat-treated ion liquid-modified reduced graphene oxide guarantees the thermal stability of an electrode material during laser cutting, and its high ion-accessible surface area improves the capacitance performance of the supercapacitor. The as-fabricated MSC demonstrates a wide voltage window (0−3 V), high areal specific capacitance (27.4 mF cm−2), and high energy density (32.1 μW h cm−2), which are far higher than those of most reported articles. Notably, the editable supercapacitors can imitate the stereo paper cutting to achieve an arbitrary one-dimensional to three-dimensional configuration, promising for various portable, stretchable, and wearable devices. KEYWORDS: editable microstructured supercapacitor, multiscale fabrication, laser direct writing, high energy density, multiple dimensions practical microdevices.4,5 Moreover, the electrode material assembled in macro-supercapacitors cannot be directly applied in MSC, which needs a particular synthesis strategy, structural readjustment, and performance evaluation and vice versa. Therefore, an editable supercapacitor with high energy density from macro- to microscale is significant for smart devices. Previous studies have successfully fabricated editable electrodes or supercapacitors with good flexibility and mechanical capacity.6−8 These editable supercapacitors are usually designed with the help of a traditional cutting mode under mild conditions, which is hard to realize the precise
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ith the rapid upgrading and renewing of various flexible and wearable electronic devices, integrated energy supply devices with arbitrary size and desired energy densities are eagerly required to match these devices, such as microrobots, microsensors, health monitors, curved mobile phones, and electronic clothing.1,2 Nowadays, there are two kinds of energy supply devices: macroscopic (macro-) and microscopic (micro-) supercapacitors (MSCs), which have progressively boomed in the energy and spread in smart devices. Although the macro-supercapacitor possesses high energy and power density, its inherent stacked geometry results in the bulky volume and low flexibility, restricting the application in the portable device.3 On the contrary, the microsupercapacitors with small volume could meet space and size requirements of the portable device. Nevertheless, the low areal energy density (
