Paper Based, Expanded Graphite/Polypyrrole Nanocomposite Supercapacitors Free from Binders and Current Collectors

UYSAL, Nilperi
Aydınlı, Alptekin
Ünalan, Hüsnü Emrah
Expanded graphite (EG) - polypyrrole (PPy) hybrid nanocomposites are used for the fabrication of paper-based highly flexible supercapacitor devices. Brush-painted EG electrodes are utilized as electrodes for the electrodeposition of PPy, resulting in the formation of nanocomposite electrodes with the desired material loading. Fabricated paper-based electrodes are free from heavy current collectors, binders, and conductive additives. Within nanocomposite electrodes, expanded graphite layer on paper facilitates the charge transfer and conformal PPy layer atop improves capacitance through pseudocapacitance. Fabricated nanocomposite electrodes are highly flexible, thanks to excellent mechanical integrity among paper, EG and PPy components. A specific capacitance of 177.8 F g(-1), in conjunction with a capacity retention of more than 94.9% is obtained following 5000 cycles. With the simple fabrication and promising electrochemical performance obtained herein, fabricated paper-based nanocomposite supercapacitors are envisaged for utilization as power sources in paper electronics. (C) 2018 The Electrochemical Society.


Reliability improvement of RF MEMS devices based on lifetime measurements
Gürbüz, Ozan Doğan; Demir, Şimşek; Akın, Tayfun; Department of Electrical and Electronics Engineering (2010)
This thesis presents fabrication of shunt, capacitive contact type RF MEMS switches which are designed according to given mm-wave performance specifications. The designed switches are modified for investigation in terms of reliability and lifetime. To observe the real-time performance of switches a time domain measurement setup is established and a CV (capacitance vs. voltage) curve measurement system is also included to measure CV curves, pull-in and hold-down voltages and the shifts of these due to actuat...
Flexible supercapacitor electrodes with vertically aligned carbon nanotubes grown on aluminum foils
Dogru, Itir Bakis; Durukan, Mete Batuhan; Turel, Onur; Ünalan, Hüsnü Emrah (2016-06-01)
In this work, vertically aligned carbon nanotubes (VACNTs) grown on aluminum foils were used as flexible supercapacitor electrodes. Aluminum foils were used as readily available, cheap and conductive substrates, and VACNTs were grown directly on these foils through chemical vapor deposition (CVD) method. Solution based ultrasonic spray pyrolysis (USP) method was used for the deposition of the CNT catalyst. Direct growth of VACNTs on aluminum foils ruled out both the internal resistance of the supercapacitor...
Electrochromic properties of multicolored novel polymer synthesized via combination of benzotriazole and N-functionalized 2,5-di(2-thienyl)-1H-pyrrole units
Rende, Eda; Kilic, Cihan E.; Udum, Yasemin Arslan; Toffoli, Daniele; Toppare, Levent Kamil (2014-08-20)
Synthesis of new conducting polymers is desired since their electrochemical and optical properties enable them to be used as active layers in many device applications. Benzotriazole and N-functionalized 2,5-di(2-thienyl)-1H-pyrrole (SNS Series) containing polymers showed very promising results as electrochromic materials. In order to observe the effect of the combination of these two units, three new monomers; 2-(6-(2,5-bis(5-methylthiophen-2-yl)-1H-pyrrol-1-yl)hexyl)-4,7-di(thiophen-2-yl)-2H benzo[d][1,2,3...
Development of electrochemical etch-stop techniques for integrated MEMS sensors
Yaşınok, Gözde Ceren; Akın, Tayfun; Department of Electrical and Electronics Engineering (2006)
This thesis presents the development of electrochemical etch-stop techniques (ECES) to achieve high precision 3-dimensional integrated MEMS sensors with wet anisotropic etching by applying proper voltages to various regions in silicon. The anisotropic etchant is selected as tetra methyl ammonium hydroxide, TMAH, considering its high silicon etch rate, selectivity towards SiO2, and CMOS compatibility, especially during front-side etching of the chip/wafer. A number of parameters affecting the etching are inv...
Impact damage sensing of multiscale composites through epoxy matrix containing carbon nanotubes
Arronche, Luciana; La Saponara, Valeria; Yesil, Sertan; Bayram, Göknur (2013-06-05)
Carbon nanotubes are used to provide increased electrical conductivity for polymer matrix materials, thus offering a method to monitor the structure's health. This work investigates the effect of impact damage on the electrical properties of multiscale composite samples, prepared with woven fiberglass reinforcement and epoxy resin modified with as-received multi-walled carbon nanotubes (MWCNTs). Moreover, this study addresses potential bias from manufacturing, and investigates the effectiveness of resistanc...
Citation Formats
R. YÜKSEL, N. UYSAL, A. Aydınlı, and H. E. Ünalan, “Paper Based, Expanded Graphite/Polypyrrole Nanocomposite Supercapacitors Free from Binders and Current Collectors,” JOURNAL OF THE ELECTROCHEMICAL SOCIETY, pp. 0–0, 2018, Accessed: 00, 2020. [Online]. Available: