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PSSA-g-PANI/Graphene Oxide 복합체의 유기태양전지 정공 수송 층으로의 적용과
Get PDF학위논문 (석사)-- 서울대학교 대학원 : 재료공학부, 2014. 2. 조원호.A new class of hole transport layer (HTL), which is composed of poly(styrene sulfonic acid) grafted with polyaniline (PSSA–g–PANI) and graphene oxide (GO), was prepared by adding GO into PSSA–g–PANI aqueous solution. The PSSA–g–PANI/GO composites exhibit high optical transparency and high electrical conductivity. When the composite with 2.5 wt% GO loading was used as HTL material for the device based on poly(3-hexylthiophene) and PC61BM, the device exhibits an enhanced power conversion efficiency (PCE) of 4.23%, which is 23% higher than the PCE of device with the conventional HTL material, PEDOT:PSS. This enhancement of PCE arises mainly from an increase of the short-circuit current density due to higher optical transparency and higher electrical conductivity of PSSA–g–PANI/GO composite.Contents
Abstract i
List of Schemes ⅳ
List of Figures ⅴ
List of Tables ⅶ
Chapter 1. Introduction 1
Chapter 2. Experimental Section 6
2.1. Materials 6
2.2. Synthesis of PSSA–g–PANI 6
2.3. Synthesis of graphene oxide 8
2.4. Preparation of PSSA–g–PANI/GO composites 12
2.4. Characterization 12
2.4. Device fabrication and characterization 13
Chapter 3. Results and Discussion 16
3.1. Synthesis and characterization 16
3.2. Optical properties 17
3.3. Electrical properties 18
3.4. Photoelectrical properties 20
3.5. Electrochemical properties 21
3.6. Photovoltaic properties 35
3.7. Discussions 44
Chapter 4. Conclusions 45
Bibliography 46
Korean Abstract 51Maste
Uyku apnesi teşhisine yeni bir bakış açısı: PSSA-g-PANI tabanlı SAW sensörü kullanarak izopren tespiti
Get PDFCellular metabolic changes triggered by Obstructive Sleep Apnea Syndrome (OSAS) are detected invasively by detecting isoprene as a biomarker of OSAS in the breath. When falling asleep, isoprene level begins to increase above 3 ppm. Therefore, monitoring isoprene levels in exhaled breath under normal conditions may provide a non-invasive method to detect, monitor, and control sleep disorders such as sleep apnea. In this study, PSSA-g-PANI based SAW gas sensors were prepared and tested against isoprene gas. Sensor measurements reveal that PSSA-g-PANI based SAW type sensor detected (1-150) ppm isoprene gas with high sensitivity and thus PSSA-g-PANI based SAW type sensor may enable monitor and control of sleep apnea.Obstrüktif Uyku Apne Sendromu (OSAS) tarafından tetiklenen hücresel metabolik değişiklikler, nefeste OSAS'ın biyobelirteci olarak izopren saptanarak invazif olarak tespit edilir. Uykuya dalındığında izopren seviyesi 3 ppm'nin üzerine çıkmaya başlar. Bu nedenle, normal koşullar altında solunan nefeste izopren seviyelerinin izlenmesi, uyku apnesi gibi uyku bozukluklarını tespit etmek, izlemek ve kontrol etmek için invazif olmayan bir yöntem sağlayabilir. Bu çalışmada, PSSA-g-PANI tabanlı SAW gaz sensörleri hazırlanmış ve izopren gaza karşı test edilmiştir. Sensör ölçümleri, PSSA-g-PANI tabanlı SAW tipi sensörün yüksek hassasiyetle (1-150) ppm izopren gazı algıladığını ve dolayısıyla PSSA-g-PANI tabanlı SAW tipi sensörün uyku apnesinin izlenmesini ve kontrolünü sağlayabileceğini ortaya koymaktadır
Enhanced performance of polymer solar cells with PSSA?g?PANI/Graphene oxide composite as hole transport layer
No full textA new class of hole transport layer (HTL), which is composed of poly(styrene sulfonic acid) grafted with polyaniline (PSSA?g?PANI) and graphene oxide (GO), was prepared by adding GO into PSSA?g?PANI aqueous solution. The PSSA?g?PANI/GO composites exhibit high optical transparency and high electrical conductivity. When the composite with 2.5 wt% GO loading was used as HTL material for the device based on poly(3-hexylthiophene)/PC61BM blend, the device exhibits an enhanced power conversion efficiency (PCE) of 4.23%, which is 23% higher than the PCE of device with the conventional HTL material, PEDOT:PSS (3.44%). This enhancement of PCE arises mainly from an increase of the short-circuit current density due to higher optical transparency and higher electrical conductivity of PSSA?g?PANI/GO composite. When the PSSA?g?PANI/GO composite is applied as HTL to a low bandgap polymer-based solar cell, PTB7:PC71BM blend, the PCE is also enhanced as compared to the device with PEDOT:PSS, providing us with the possibility to use PSSA?g?PANI/GO as a hole transport layer for various polymer-based solar cells to enhance the photovoltaic performance.OAIID:oai:osos.snu.ac.kr:snu2014-01/102/0000001236/5SEQ:5PERF_CD:SNU2014-01EVAL_ITEM_CD:102USER_ID:0000001236ADJUST_YN:NEMP_ID:A004558DEPT_CD:445CITE_RATE:5.03FILENAME:5. enhanced performanceofpolymersolarcellswithp.pdfDEPT_NM:재료공학부SCOPUS_YN:YCONFIRM:
Enhanced Performance of Polymer Solar Cells with PSSA-g-PANI/Graphene Oxide as Hole Transport Layer
No full textHole transport layer (HTL) has always been used for high performance polymer solar cells (PSCs) because of efficient hole extraction from active layer to anode and lowering the contact resistance between active layer and anode. Although PEDOT:PSS has commonly been used as a HTL, it has detrimental problems with low electrical conductivity, acidic nature and large aggregates. As an alternative to PEDOT:PSS, we previously synthesized poly(styrenesulfonic acid)-graft-polyaniline (PSSA-g-PANI) which is a self-doped conducting copolymer, and reported significant enhancement of the power conversion efficiency (PCE) of PSCs when it was used as a HTL of PSCs. In this work, we prepared PSSA-g-PANI/graphene oxide (GO) composite by adding GO into PSSA-g-PANI and used the composite as HTL of PSCs for the purpose to further improve the PCE. When the PSSA-g-PANI/GO (95/5) composite was used as HTL, the PCE of PSCs was improved by about 10% as compared to that without GO.OAIID:oai:osos.snu.ac.kr:snu2013-01/104/0000001236/12SEQ:12PERF_CD:SNU2013-01EVAL_ITEM_CD:104USER_ID:0000001236ADJUST_YN:NEMP_ID:A004558DEPT_CD:445CITE_RATE:0FILENAME:0411 12_박흥수.pdfDEPT_NM:재료공학부EMAIL:[email protected]:
Going Beyond Counting First Authors in Author Co-citation Analysis
Get PDFThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
Variations on the Author
Get PDF“Variations on the Author” discusses two of Eduardo Coutinho’s recent films (Um Dia na Vida, from 2010, and Últimas Conversas, posthumously released in 2015) and their contribution to the general question of documentary authorship. The director’s filmography is characterized by a consistent yet self-effacing form of authorial self-inscription: Coutinho often features as an interviewer that rather than express opinions propels discourses; an interviewer that is good at listening. This mode of self-inscription characterizes him as an author who is not expressive but who is nonetheless markedly present on the screen. In Um Dia na Vida, however, Coutinho is completely absent form the image, while Últimas Conversas, on the contrary, includes a confessional prologue that moves the director from the margins to the center of his films. This article examines the ways in which these works stand out in the filmography of a director who offers new insights into the notion of cinematic authorship
Appropriate Similarity Measures for Author Cocitation Analysis
Get PDFWe provide a number of new insights into the methodological discussion about author cocitation analysis. We first argue that the use of the Pearson correlation for measuring the similarity between authors’ cocitation profiles is not very satisfactory. We then discuss what kind of similarity measures may be used as an alternative to the Pearson correlation. We consider three similarity measures in particular. One is the well-known cosine. The other two similarity measures have not been used before in the bibliometric literature. Finally, we show by means of an example that our findings have a high practical relevance.information science;Pearson correlation;cosine;similarity measure;author cocitation analysis
Dispelling the Myths Behind First-author Citation Counts
Get PDFWe conducted a full-scale evaluative citation analysis study of scholars in the XML research field to explore just how different from each other author rankings resulting from different citation counting methods actually are, and to demonstrate the capability of emerging data and tools on the Web in supporting more realistic citation counting methods. Our results contest some common arguments for the continued
use of first-author citation counts in the evaluation of scholars, such as high correlations between author rankings by first-author citation counts and other citation
counting methods, and high costs of using more realistic citation counting methods that are not well-supported by the ISI databases. It is argued that increasingly available digital full text research papers make it possible for citation analysis studies to go beyond what the ISI databases have directly supported and to employ more
sophisticated methods
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