Fully integrated rechargeable pedot : PSS energy storage device for smart textiles applications

Energievoorziening en opslag is een belangrijk onderdeel van slimme textielsystemen omdat het de vereiste energie levert om het systeem van stroom te voorzien. Deze thesis is een voortzetting van een vorige studie, en was vooral gericht op het verbeteren van de prestaties en het uiterlijk van het onderdeel door de verbetering van de fabricagetechnieken en het onderzoeken van het werkingsprincipe en mechanisme van de TESD component. De ontwikkelde component transformeerde, van de vroegste naar de nieuwste vorm, via vier verschillende en verbeterde fabricagemethoden die de prestaties en het uiterlijk van het apparaat verbeterden. De component met de naam TESD 1.2 THL is de beste vorm van ons textiel-energieopslagonderdeel tot nu toe. Uit de studie van het mechanisme werd complex gedrag van ionische en elektronische oorsprong waargenomen in het grensvlakgebied van het gebruikte geleidende polymeer, PEDOT:PSS. Een grotere verhouding van PEDOT tot PSS, met een hogere soortelijke weerstand, is wenselijk, maar verder onderzoek is nodig. Weerstand tegen wassen van het apparaat en het conceptontwerp voor de integratie van onze TESD in kleding werd ook uitgewerkt. Over het geheel genomen lieten de resultaten veelbelovend potentieel zien voor de verdere ontwikkeling van een op textiel gebaseerd energieopslagapparaat

STUDI PEMBUATAN FILAMEN ANTIULTRAVIOLET DARI POLIMER POLIPROPILENA DAN NANOPARTIKEL SENG OKSIDA DENGAN METODE PEMINTALAN LELEH

Peningkatan kemampuan kain sintetik untuk memproteksi efek negatif radiasi ultraviolet (UV) dapat diperoleh dengan proses penyempurnaan menggunakan nanopartikel seng oksida (ZnO). Teknologi konvensional yang menggunakan modifikasi permukaan dengan penyempurnaan basah ataupun teknologi plasma sebagian besar memiliki kekurangan, terutama dalam hal durabilitas sifat fungsional. Salah satu metode yang dapat diaplikasikan untuk meningkatkan durability sifat fungsional kain adalah melalui pembuatan filamen dengan metode pemintalan leleh. Tujuan dari penelitian ini adalah untuk mendapatkan filamen yang memiliki sifat antiUV dan durability yang lebih baik daripada proses pad-dry-cure (rendam peras-pengeringan-pemanasawetan). Pembuatan filamen fungsional anti ultraviolet diawali dengan pembuatan campuran nanopartikel seng oksida dan chip polipropilena dengan variasi konsentrasi nanopartikel ZnO sebelum diproses pada mesin pemintalan leleh skala laboratorium. Metode pencampuran chip polipropilena dan nanopartikel ZnO yang digunakan adalah bikomponen dengan penampang filamen core and sheath. Evaluasi dan karakterisasi dilakukan terhadap morfologi filamen, nomor benang, dan kekuatan tarik benang serta performa antiUV melalui pengukuran ultraviolet protection factor (UPF). Hasil penelitian pada filamen dengan konsentrasi nanopartikel ZnO mulai dari 0 - 1% menunjukkan peningkatan nilai UPF mulai dari 87-241% dan penurunan kekuatan tarik benang mulai dari 7,4-15,4%. Performa terbaik didapatkan pada filamen dengan konsentrasi nanopartikel ZnO 0,75% yang memiliki hasil UPF kain sebesar 8,2, jauh lebih tinggi dibandingkan dengan kain hasil penyempurnaan menggunakan proses pad-dry-cure yang hanya memiliki nilai 3,9

Electrochemical impedance analysis of a PEDOT : PSS-based textile energy storage device

A textile-based energy storage device with electroactive PEDOT:PSS (poly(3,4-ethylenedioxythiophene)/poly(4-styrenesulfonate)) polymer functioning as a solid-state polyelectrolyte has been developed. The device was fabricated on textile fabric with two plies of stainless-steel electroconductive yarn as the electrodes. In this study, cyclic voltammetry and electrochemical impedance analysis were used to investigate ionic and electronic activities in the bulk of PEDOT:PSS and at its interfaces with stainless steel yarn electrodes. The complex behavior of ionic and electronic origins was observed in the interfacial region between the conductive polymer and the electrodes. The migration and diffusion of the ions involved were confirmed by the presence of the Warburg element with a phase shift of 45° (n = 0.5). Two different equivalent circuit models were found by simulating the model with the experimental results: (QR)(QR)(QR) for uncharged and (QR)(QR)(Q(RW)) for charged samples. The analyses also showed that the further the distance between electrodes, the lower the capacitance of the cell. The distribution of polymer on the cell surface also played important role to change the capacitance of the device. The results of this work may lead to a better understanding of the mechanism and how to improve the performance of the device

Fastness Improvement of a Crystalline Liquid Thermochromic Print on Cotton Fabric by the Application of Silica Nanoparticles from Rice-Husk

Most commercially available thermochromic dyes are not resistant to washing and rubbing when applied to textile materials. This is due to their low affinity for fibre. The addition of silica extracted from rice husk ash using the sol-gel method was performed to improve colour fastness and maintain the stability of thermochromic dyes printed on cotton fabrics. The rice husks used in this study were derived from the Baroma rice variety with silica content in ash and silica gel of 97.05% and 99.20%. The morphological structures and particle sizes of the silica obtained were analysed using a scanning electron microscope (SEM) and particle size analyser (PSA). The particle sizes of the silica product, thermochromic dye and silica-dye mixture were 53.64–60.66 nm, 2.603 nm and 5.827 nm, respectively. The printing process of silica: the dye mixture was applied to cotton fabric in a ratio of 1:1. Fluid of silica: the dye showed good stability until the seventh day of observation. Colour fastness to washing assessed using a staining scale was better with the addition of silica than without silica, i.e. 3–4 in the first washing and 3 in the third washing. Similarly, fastness to rubbing was also better with the addition of silica, i.e. 3–4 dry rubbings and 3 wet rubbings. Moreover, the combination of silica, binder, PDMS and dye (in a ratio of 1:1:1:1) gave the best colour fastness to washing and rubbing

Study on capacitive behaviour of PEDOT:PSS-based energy storage device by modeling the charge-discharge profile

We have fabricated a functional facile textile energy storage device made of a pair of stainless steel conductive yarns coated with poly(3,4-ethylenedioxythiophene):poly(styrenesulfonate) (PEDOT:PSS) film. The devices having d 1, 2, and 3 mm with different sources of polymer were put to a series of charge-discharge measurements to determine each capacitive behaviour. The charge-discharge profiles showed disagreement with theoretical calculation for a capacitor made of two parallel wires. Capacitance was found to decrease with distance between yarn electrodes. PEDOT:PSS from two different sources showed different behaviour, indicating the role of the polymer in the energy storage mechanism

Charge-discharge characteristics of textile energy storage devices having different PEDOT:PSS ratios and conductive Yarns configuration

Conductive polymer PEDOT:PSS, sandwiched between two conductive yarns, has been proven to have capacitive behavior in our textile energy storage devices. Full understanding of its underlying mechanism is still intriguing. The effect of the PEDOT to PSS ratio and the configuration of the electrode yarns are the focus of this study. Three commercial PEDOT:PSS yarns, Clevios P-VP-AI-4083, Ossila AI 4083, and Orgacon ICP 1050, as well as stainless steel and silver-coated polybenzoxazole (Ag/PBO) yarns, in various combinations, were used as solid electrolytes and electrodes, respectively. Analyses with NMR, ICP-OES, TGA, and resistivity measurement were employed to characterize the PEDOT:PSS. The device charge-discharge performance was measured by the Arduino microcontroller. Clevios and Ossila were found to have identical characteristics with a similar ratio, that is, 1:5.26, hence a higher resistivity of 1000 Ω.cm, while Orgacon had a lower PEDOT to PSS ratio, that is, 1:4.65, with a lower resistivity of 0.25⁻1 Ω.cm. The thermal stability of PEDOT:PSS up to 250 °C was proven. Devices with PEDOT:PSS having lower conductivity, such as Clevios P-VP-AI-4083 or Ossila AI 4083, showed capacitive behavior. For a better charge-discharge profile, it is also suggested that the PEDOT to electrode resistance should be low. These results led to a conclusion that a larger ratio of PEDOT to PSS, having higher resistivity, is more desirable, but further research is needed

Towards Environmentally Benign Wastewater Treatment - Photocatalytic Study of Degradation of Industrial Dyes

Pollution created by textile dyeing operations attracts significant attention because an effluent containing a complex mixture of coloured and potentially toxic compounds can be released with the discharged water. Developing dyes and dyeing conditions to reduce the amount of residual dye contained in any effluent has been one of many approaches to minimise this environmental impact. However, the presence of coloured discharge cannot be totally eliminated using only this strategy. Thus, development of efficient post-dyeing wastewater treatment methods capable of removing coloured products from the water is of paramount importance. TiO2-mediated photocatalytic degradation of organic dye molecules via oxidation is the focus of the study reported in this thesis. TiO₂ significantly increases the rate of photodegradation of a wide range of organic dyes under mild operating conditions, and is able to mineralise a wide spectrum of organic contaminants. TiO₂ is also one of the very few substances appropriate for the industrial applications. One of primary aims of this thesis is to test the hypothesis that augmenting standard TiO₂ photocatalysts with Au nanoparticles could increase performance of a catalyst, while immobilizing TiO₂ on SiO₂ support may improve the cost of the process efficiency, i.e. more photocatalytic degradation per particle of TiO₂. Combining TiO₂ doped with gold nanoparticles on SiO₂ support has the potential to provide the highest photocatalytic ability at the lowest cost. The first half of the thesis is concerned with establishing and optimizing experimental conditions for monitoring photodegradation via UV-Visible spectroscopy. Effects of various conditions such as temperature, sequence of addition of reagents, exposure to light vs. experiments in dark, sampling methods, and the use of quenching agent were examined. The main conclusions from this study are that light-induced photodegradation using titanium dioxide nanoparticles catalysts is comparatively more efficient than purely chemical catalytic (e.g. non-light mediated) degradation, even if the latter is performed at elevated temperature. Further, the rate of dye degradation is affected considerably by the parameters of the system. The degradation rate depends strongly on the pH of the solution, due to charges on both the catalyst surface and in the dye. In general, at pH ≤ 6.8, which is the zero charge point for TiO₂, reactions proceeded faster than those at higher pH. Six dyes from four different classes of dyes used in industry were used in this study, and all showed different photodegradation behaviour. The second half of thesis tests the photocatalytic abilities of various TiO₂-based catalysts: pure TiO₂ (commercial and custom-made in our laboratory), TiO₂-supported gold nanoparticles (Au/TiO₂), SiO₂-supported TiO₂ (TiO₂/SiO₂), and SiO₂-supported Au/TiO₂. The best photocatalytic performance was observed for the custom-made TiO₂ code-named as e-TiO₂, which was synthesized using the sol-gel method in dry ethanol. TiO₂-supported Au55 nanoparticles showed a similar level of catalytic ability but are significantly more expensive. It was observed that dye adsorption played a significant role in the case of SiO₂-immobilized photocatalysts

KARAKTERSITIK ZAT WARNA TERMOKROMIK TOUCH ACTIVATED DAN HASIL PENCAPANNYA PADA KAIN KAPAS

Zat warna termokromik, yang dikategorikan sebagai salah satu jenis smart dyes, dikembangkan terutama untuk memperoleh aspek-aspek fungsional pada bahan tekstil melalui kemampuannya untuk merespon rangsangan tertentu. Zat warna termokromik jenis touch activated dapat memudar warnanya ketika disentuh (pada suhu 29 o C / 84 o F). Kebutuhan untuk melengkapi informasi mengenai aspek-aspek teknis aplikasi dan karakteristik zat warna termokromik komersial jenis touch activated mendorong dilakukannya penelitian ini. Penelitian dilakukan dengan mengaplikasikan zat warna tersebut pada kain kapas dengan metode pencapan. Perbandingan zat warna:binder sebesar 1:1 dan diikuti dengan fiksasi pada temperatur ruang selama 30 menit. Hasil analisa FTIR menunjukkan bahwa zat warna tersusun atas senyawa organik aromatik dengan beberapa puncak serapan yang dominan seperti C=O, C=C, dll. Kain hasil pencapan memudar setelah menerima rangsangan sentuhan dan bersifat reversibel. Perbedaan usia dan jenis kelamin responden yang melakukan stimulus sentuhan tidak berpengaruh secara signifikan pada waktu retensi respon perubahan warna kembali. Ketahanan luntur warna kain hasil pencapan terhadap pencucian cukup rendah (nilai staining scale mencapai 2-3). Zat warna termokromik jenis touch activated lebih tepat digunakan untuk kepentingan teknis dan estetis pada aplikasi di bidang garmen atau untuk aplikasi sensor dan sejenisnya

Electric field effect on charge-discharge characteristics of textile-based energy storage devices : in search of the underlying mechanism

The work focused on studying the eff ect of charging voltage level and the absence of electrode between the measured electrodes on the charge storage profi le. The device was applied on a three layered of 5 x 5 cm laminated textile fabric with hydrophobic surface. Stainless steel fi lament yarns were used as electrodes. As electrolyte, seven layers of the electro-active polymer PEDOT:PSS dispersion was consecutively drop-coated and dried under the temperature of 90–100 °C. During the course of the experiments, the devices were charged and discharged and their response or voltage decay was recorded. The results showed that the higher the charging voltage, the higher the amount of charges stored. The increase in the output voltage was not proportional to the input voltage which means that the device did not behave as either a pure capacitor or a pure battery. The ions movement was confi rmed to be involved in the charge-discharge mechanism of the device