초등학교 미술 교육에서 효과적인 판화 지도방안에 관한 연구

변수진 국민대학교 교육대학원 2002 국내석사

Abstract : p.58-59

Lactobacillus plantarum Hong KFCC 11556P를 이용한 농산가공부산물의 dihydroferulic acid 생산 수율 증진을 위한 연구

변수진 인제대학교 일반대학원 2024 국내석사

In this study was to enhancement of phenolic compounds and antioxidant activity in rice bran (RB) and corn bran (CB) using Lactobacillus plantarum Hong KFCC 11556P. The lactic acid bacteria proliferated in RB and CB for 48 h, reaching 9.38±0.05, 8.26±0.06 log CFU/g, respectively. The pH values were 5.61±0.01 and 4.14±0.03. The acidity of RB and CB were 0.84±0.01 and 0.19±0.02%, respectively. Total polyphenol content (TPC) was increased during fermentation time, ranging from 3.87 to 4.71 μg/ml for RB and from 3.46 to 5.19 μg/ml for CB. Both RB and CB exhibited the highest TPC content at 48 h of fermentation. The antioxidant activity (DPPH, ABTS) was higher in the fermented extracts (fermented rice bran(FRB), fermented corn bran(FCB)) compared to the control groups (RB, CB). The Scanning electron microscopy (SEM) analysis indicated a porous structure in FRB and FCB. The phenolic acids of RB and CB were determined using High-Performance Liquid Chromatography (HPLC). The HPLC analysis revealed a significant increase in dihydroferulic acid (dFA) at FRB. To establish optimal conditions for enhancing dFA production in rice bran medium, we evaluated the ferulic acid addition and fermentation time during rice bran fermentation. Control group (without adding ferulic acid) was produced 0.71±0.08 g/L of dFA after fermentation. In the ferulic acid addition group, a significant increase in dFA production was observed as the concentration increased. In particular, 0.03% ferulic acid addition was determined the highest production of dFA, while groups with concentrations exceeding 0.03%, showed decrease in dFA production. Furthermore, the study investigating the influence of fermentation time on dFA production revealed that the highest production occurred at 48 h of fermentation following the addition of 0.03% ferulic acid. Therefore, the optimization condition of dFA production in fermentation of rice bran was established at 35℃, 48 h of fermentation, and 0.03% ferulic acid. 지구온난화 등의 환경적 요인으로 인해 식량자원의 감소가 가속화되고 있으며, 이러한 관점에서 그동안 저가치화 또는 폐기되는 농산가공부산물의 이용을 위한 연구가 다양하게 진행되고 있다. 특히, 곡류 식품의 가공 중 발생하는 곡물의 겨에는 페룰산과 같은 생리활성 성분이 풍부한 것으로 알려져 있다. 본 연구에서는 농산가공부산물인 미강(RB)과 옥수수겨(CB)의 페놀화합물과 항산화 활성 향상을 위해 김치에서 분리된 Lactobacillus plantarum Hong KFCC 11556P를 이용하는 생물전환 발효연구를 통해 미강과 옥수수겨의 페룰산 및 그 대사물질을 분석하였다. 미강과 옥수수겨는 발효 48시간에서 각각 9.38±0.05, 8.26±0.06 log CFU/g의 유산균이 증식하는 것으로 나타났다. pH는 각각 5.61±0.01, 4.14±0.03을 나타냈으며 산도는 0.84±0.01, 0.19±0.02%였다. 총 폴리페놀 함량(TPC)은 발효시간이 증가함에 따라 미강의 경우 3.87∼4.71 μg/ml의 범위를 보였으며, 옥수수겨의 경우 3.46∼5.19 μg/ml의 범위를 보였다. 미강과 옥수수겨 모두 발효 48시간에서 가장 높은 TPC 함량을 나타내었다. 발효물의 항산화 활성(DPPH, ABTS)은 대조군(RB, CB)보다 미강발효물(FRB)과 옥수수겨발효물(FCB)에서 더 높았으며, 주사전자현미경(SEM) 분석결과 미강과 옥수수겨 모두 발효 후에 다공성의 구조를 가지는 것을 보여주었다. 미강과 옥수수겨의 유용성분은 고성능 액체 크로마토그래피(HPLC)를 사용하여 확인하였다. HPLC 분석결과 FRB에서 Dihydroferulic acid(dFA)의 유의한 증가를 확인하였다. 유용성분인 dFA의 생산 최적화를 위해 페룰산 첨가 및 발효시간에 따른 생산능력을 평가하였다. 페룰산 무첨가 군에서는 발효 후 0.71±0.08 g/L의 dFA가 생성되었으며, 페룰산 첨가 군의 경우 농도가 증가할수록 dFA 생산 함량이 유의적으로 증가하는 것을 확인할 수 있었다. 특히, 페룰산 0.03% 첨가 군에서 가장 높은 생성능을 나타내었으며, 0.03% 이상 처리군에서는 생성량이 감소하는 것으로 나타났다. 또한, 발효시간에 따른 dFA 생산량을 조사한 결과 0.03% 페룰산 첨가 후 발효 48시간에서 가장 높은 생산량을 나타내었다. 본 연구결과에 따르면 35℃, 발효 48시간, 페룰산 첨가량 0.03% 조건으로 2.25±0.02 g/L dFA 생산량을 나타내었다.

비대면 시대 소통을 위한 중학교 미술 이모티콘 수업 연구

변수진 전남대학교 2021 국내석사

'Communication' is when two individuals send and receive their thoughts, emotions and such via language and actions, thus interacting. In the past, most communication happened by the individuals meeting in person, but after the Fourth Industrial Revolution, with the widespread use of computers and smartphone, communication went online and not face-to-face. Especially as the era of online affairs for the prevention of COVID-19 came upon us, communication through online messengers and social media skyrocketed. In this Untact era, effective communication is difficult because we are unable to full understand one's verbal and non-verbal expressions. Therefore, study was done on the production of emoticons and the application in education in order for one to express their feelings and opinions visually and communicate effectively. A revised 2015 edition of a curriculum by the Ministry of Education stated a proposal for 10 policy tasks for the future of education after COVID-19. Furthermore, the revised edition would take into consideration the interests and satisfaction of the learners by producing emoticons that they could apply in their daily lives and share. The audience of this study were 35 male and 40 female students in their third grade from Gwangju of ‘H’ middle school, who were taking the emoticon class for their first time. After taking the class, they each wrote one sentence about their thoughts of the class. Based on all the results, the reasons for satisfaction were analyzed. By applying this study in the class, the students can learn more about their inner-self by looking deeply into themselves in the process of producing emoticons. Through this, character building education can be possible by emphasizing the importance of communication and consideration for others. In addition, by utilizing the emoticons made in their real-life to communicate in messenger, communication with accuracy will be possible. In addition, convergence classes applying achievement standards related to understanding, consideration, and communication of other subjects are possible, so they can be practically used in schools. By expressing the contents of the curriculum as emoticons in a fun and humorous way, the barriers to entry into the contents of the curriculum can be lowered. Through the teaching methods recommended in this study, we hope the students can effectively communicate and relay messages as well as understand themselves, others, and the world while enjoying interaction. In particular, in the lack of communication between those of one's age group in this COVID-19 era, we hope that through the use of emoticons, one can easily communicate and express one's mind. ‘소통’이란 둘 이상의 당사자가 말이나 행동을 통하여 자기 생각과 감정 등을 주고받음으로써 상호 작용하는 것을 의미한다. 과거에는 당사자가 서로 직접 만나서 소통하는 일이 다수였으나 4차 산업혁명 이후 컴퓨터 및 스마트 폰 사용의 대중화로 소통의 방식이 온라인 비대면 소통으로 변화하였다. 특히 최근 코로나 19 감염 예방을 위한 비대면 시대가 도래하면서 모바일 메신저 및 소셜 네트워크를 통한 소통이 급증하였다. 이러한 비대면 상황에서의 의사소통은 상대의 반언어적 표현과 비언어적 표현을 감지할 수 없으므로 효과적인 의사소통이 어렵다. 따라서 비대면 시대에 자신의 감정과 의사를 시각적으로 표현하고 타인과 효과적으로 소통할 수 있는 이모티콘의 제작 교육 및 교육현장에의 적용 방안에 관해 연구하였다. 본 연구는 교육부에서 발표한 ‘코로나 이후, 미래 교육 전환을 위한 10대 정책과제(안)’를 반영하고, 교육부에서 제시한 2015 개정 교육과정을 토대로 하였다. 이를 바탕으로 2015 개정 교육과정 미술 교과서를 분석하되 학습자의 수준과 흥미 및 만족도를 고려하여 이모티콘 제작하고 실생활에 적용한 후 이를 공유하는 수업구성안을 제작하였다. 본 연구의 대상은 이모티콘 수업을 처음 학습하는 광주광역시 ㅎ중학교 3학년 남자 35명, 여자 40명 총 75명이다. 수업을 적용한 뒤 수업에 대한 한 줄 소감을 작성하게 하였다. 한 줄 소감을 바탕으로 만족도 결과를 도출한 다음 그 이유에 대해 분석해보았다. 본 연구를 수업에 반영함으로써 학습자가 이모티콘의 제작과정에서 자신의 마음을 스스로 들여다보며 내면을 깊이 이해하도록 지도할 수 있다. 또한, 자신이 제작한 이모티콘을 실생활에서 동료학습자와 메신저 소통 시 활용함으로써 대화 당사자 간 의사와 감정을 보다 정확하게 인지할 수 있으므로 원활한 의사소통이 가능해질 것이다. 이때 소통, 배려 등의 덕목을 강조함으로써 인성교육이 가능하므로 전인교육을 도모할 수 있다. 또한, 타 교과의 이해 및 배려, 소통에 관련 성취기준을 적용하여 융합 수업이 가능하므로 학교에서 실질적으로 활용할 수 있다. 교과 내용을 재미있고 익살스럽게 이모티콘으로 표현하여 교과에 대한 진입 장벽을 낮출 수 있다. 더 나아가 학습자의 수업 흥미도 및 학업 성취도를 향상할 수 있다. 더불어 비대면 시대를 맞이하여서도 이모티콘 수업의 적극적 활용으로 입시 경쟁 위주의 비전문 교과였던 미술교육에도 크나큰 발전을 도모할 수 있다. 본 연구에 제시된 수업 방법을 통하여 학습자가 자신의 마음을 들여다보고 이를 효과적으로 전달하는 소통능력을 기름으로써 자신과 타인과 세계를 이해하고 소통하는 즐거움을 느끼기를 바란다. 특히 또래와의 소통 창구가 부족한 코로나 19시대에 이모티콘을 통한 타인과 원활한 소통을 통해 마음의 면역력 또한 증진되기를 기대한다.

학교기업의 재무제표 현황 및 회계처리 개선방안

변수진 강원대학교 대학원 2010 국내석사

For effective education focusing on the actual businesses, the colleges have been suggesting the school-industry cooperation as the integrated education approach which intensively mobilizes all necessary resources. A school-based enterprise is an entity affiliated to a school, which engages in manufacturing, sales, repair or processing of goods or providing service in connection with a specific department or curriculum of the school as one of school-industry cooperation types. A school-based enterprise enables students to have the opportunity to have work experience related to their curriculum and to acquire the ability required on the field by directly participating in diverse activities of enterprises. Through such processes, a school can get the financial support from the profits created through the operation of school-based enterprise as well as promote the transfer of technology to industries, enhance the research ability of faculty members and cultivate the competent persons. The effective operation of school-based enterprise will create educational, economic and social benefits. However, in spite of the purposes of their introduction, school-based enterprises have been facing a variety of institutional difficulties with very poor revenue structure to the extent that they can't sustain the operation without the financial support including government subsidies except several superior schools. This study investigated the status of school-based enterprises on the basis of the financial statements of universities and colleges from 2007 to 2008 which were the financial settlement published by Korea Foundation for the Promotion of Private School, and analyzed those financial statements and the status. In accordance with the analysis, total assets and total liabilities on the balance sheet from 2007 and 2008 were higher in colleges than in universities. In particular, for the long-term liabilities, the colleges and universities accounted for 1.4% and 98.6% in 2007, respectively, and the difference between colleges and universities was more significant in 2008, 31.9% and 47.2%, respectively. The endowment fund was increased for colleges from 31.9% to 47.2% but decreased for universities from 68.1% to 52.8%. For the operating statements of school-based enterprises, the ratio of non-operating revenues in total revenues in 2007 and 2008 was lower than that of sales. It was also found that selling and administrative expenses accounted for higher ratio than the costs of goods sold. The ratio difference between costs of goods sold and selling and administrative expenses was higher in colleges than universities. This study identified several problems in financial statements of school-based enterprises including cost of goods sold higher than unappropriated sales and depreciation settlement and suggested the approaches to solve such problems caused by insufficient awareness on accounting. First, the institutional support shall be improved for the application of unified accounting principles by school-based enterprises. Second, school-based enterprises and relevant organizations need to recognize the importance of financial statements. Third, it is required to intensify the education on accounting persons in school-based enterprises and activate the professional consulting. Finally, it is necessary to activate the organization which can comprehensively manage and support school-based enterprises. This study is significant because it identified the status and problems of school-based enterprises on the basis of the actual financial statements of school-based enterprises, unlike the previous researches trying to find out the approaches to develop school-based enterprises for school-industry cooperation or work experience or theoretic researches on school-based enterprises, and suggested the approach to solve such problems. However, it was difficult to collect data because there is no organization to collect and manage statistical data on school-based enterprises. Furthermore, since the number of school-based enterprises included in the analysis was less than the number of school-based enterprises which are currently operating, this study has certain limits including significant influence of a certain items of a specific school-based enterprise on all school-based enterprises. The further study needs to intensively examine by collecting more data on school-based enterprises. 최근 대학은 실무위주의 교육을 효율적으로 실시하기 위하여, 필요한 자원을 집중적으로 동원하는 통합적인 교육 방안으로 산학협동을 제시하고 있다. 학교기업은 이러한 산학협동 유형의 하나로 특정 학과 또는 교육과정과 연계하여 물품의 제조․판매․수선․가공 또는 용역의 제공 등을 행하는 학교 부속의 부서이다. 학교기업은 학생들이 교육과정의 현장실습은 물론이고 직접 기업 활동에 참여해 봄으로써 직업현장에서 필요한 능력을 습득할 수 있다. 이러한 과정을 통해 학교는 우수한 인력양성과 교원의 연구능력 발전, 산업체 등으로의 기술이전 촉진은 물론이고 학교기업의 운영활동을 통한 수익으로 재정지원에 도움을 받을 수도 있다. 학교기업의 효율적인 운영은 교육적 효과, 경제적 효과, 사회적 효과를 기대할 수 있다. 그러나 학교기업은 그 도입취지에도 불구하고 몇몇 우수 학교를 제외하고는 국고보조금 등의 지원금 없이는 운영이 어려울 정도로 매우 열악한 수익구조와 여러 제도적 어려움을 겪고 있다. 본 연구는 한국사학진흥재단 결산 공시 자료로 입수한 2007년~2008년도 4년제 대학 및 전문대학의 재무제표를 통해 학교기업의 현황을 살펴보고, 이에 대한 분석을 실시하였다. 분석결과, 2007년과 2008년의 대차대조표 자산총계, 부채총계에서 4년제 대학의 비중보다 전문대학의 비중이 높게 나타났다. 특히 고정부채의 경우 2007년 4년제 대학과 전문대학간의 비중이 각각 1.4%, 98.6%, 2008년도 각각 8.77%, 91.3%로 월등한 차이를 보였다. 기본금의 경우 전문대학의 비중은 31.9%에서 47.2%로, 4년제 대학이 68.1%에서 52.8%로 반전되는 결과를 보여주었다. 학교기업의 운영계산서의 경우 2007년과 2008년 모두 수익총계에서 운영외수익보다 매출액의 구성 비율이 높게 나타났으며, 매출원가보다 판매비와관리비가 높은 구성 비율로 나타났다. 매출원가와 판매비와관리비의 구성 비율의 차이는 4년제 대학에 비해 전문대학이 높게 나타났다. 또한 매출원가 미계상, 매출액보다 큰 금액의 매출원가, 감가상각비 처리 문제 등을 학교기업 재무제표 사례를 통해 지적하고, 회계에 대한 인식부족으로 인한 문제점을 해결할 수 있는 방안은 다음과 같이 제시하였다. 첫째, 학교기업 간의 통일된 회계처리 방법을 적용할 수 있도록 제도적 지원을 강화하여야 한다. 둘째, 학교기업과 관련기관이 재무제표의 중요성을 인식할 필요가 있다. 셋째, 학교기업 회계담당자에 대한 교육을 강화하고, 전문가 컨설팅을 활성화 하여야 한다. 넷째, 학교기업에 대해 통합적인 관리 및 지원을 담당하는 기관이 활성화 되어야 한다. 학교기업에 대한 이론적 연구나 산․학협력 또는 학생실습을 위한 학교기업의 발전방안을 모색한 선행연구들과는 달리 학교기업의 실제 재무제표를 통해 학교기업의 현황 및 문제점을 지적하고, 그에 대한 개선방안을 제시하였다는 점에서 의의가 있다. 그러나 학교기업에 대한 통계자료를 취합․관리하는 기관이 없어 자료 수집에 어려움이 있었고, 분석을 실시한 학교기업의 수가 현재 운영 중인 실제 학교기업 수에 비해 적었기 때문에 특정 학교기업의 항목이 전체에 큰 영향을 미치는 등 결과에 한계점이 있다. 추후 더 많은 학교기업의 자료를 취합하여 상세한 연구가 필요하다.

秦代 農家의 家族類型과 家內經濟

변수진 경북대학교 대학원 2020 국내석사

針對中國古代的家庭類型問題,學界普遍認爲商鞅改革屬於強制分戶政策,即,秦代的家庭類型屬於以夫婦爲中心的個體小家庭。直至20世紀70年代末,隨著大量簡牘的陸續出土,學者們根據相關資料發現除個體小家庭之外,還有其他家庭類型並存的可能性。雖然目前有關經濟方面的相關研究並不充分,但本文仍以前述可能性爲主旨,從經濟角度來考察秦代家庭類型、農家經濟規模與秦朝的農家保護政策。 首先,通過以“戶”“同居”“室人”等爲中心的法律用語考察國家所認識的家庭類型,其中不僅包括個體小家庭,還包括由父母、妻子、同産組成的三族制家庭。特別是有可能將《嶽麓秦簡》中記錄的“室人父母妻子同産”解釋爲“室人的室人範圍”。即,“室人的父母、妻子、同産”。因此,可見屬於“室人”範疇的具體家庭成員還包括相當於三族制家庭的父母、妻子、同産 。 其次,爲了解是否在行政方面也考慮到多種家庭類型,以在嶽麓秦簡、里耶秦簡中看到的戶賦爲中心進行了考察。嶽麓秦簡規定的“戶賦”可以整理如下:第一,基本規定。一年中戶賦分爲5月與10月兩次交納,即在5月份繳納16錢、在10月份繳納芻1石15斤;第二,可以用布或16錢來代替,如果用錢來代替繳納10月戶賦的話,就叫做“戶芻錢”,每年的戶賦總額爲32錢;第三,征收對象的最基本條件是“爲戶”,具備單獨的戶籍,其中戶主的爵位爲從18級大庶長到下爲司寇、隱官;第四,認爲被推測爲特定身份男性的“敖童”也是需要傅籍繳納戶賦的對象。從這一點來看,戶賦的征收對象是居住在戶內的所有成年男性。以此爲基礎,本文分析了里耶秦簡所載“戶芻錢六十四”。通過與特殊戶賦“繭”的收受憑證資料的比較,可以看出“戶芻錢六十四”是記錄1戶在10月繳納戶芻錢的文件。因此,可推測繳納戶芻錢64錢的戶是相當於4名成年男子同居的形式。 另外,李悝描述的1戶是由夫婦和他們的未成年子女共5人組成的個體小家庭,經濟上長期持續赤字狀態。然而,通過與簡牘的比較發現,李悝爲強調采納“盡地力之教”,有意地描繪經濟規模小的農家形態。以此爲據,將可估計的農家經濟規模整理如下:假如家庭類型爲老母親、1對夫妻和兩名未成年子女同居的形態,所得結論與“盡地力之教”不同,還有剩下相當於成年男性兩年份的食費金額。但此種收益是在家內至少保持以兩名成年男女爲中心的充分農業勞動力,並且要消費與刑徒差不多的食費和服裝費才能得到的。因此可知,即便不出現經濟赤字,當時農戶的消費相當於主農作物的生産量。如果遇到荒年或者出現農業勞動力不足等因素,就有可能無法維持當年的農業生産。 最後考察的問題是國家爲保持農家而實行的政策。作者認爲,可以將商鞅的第一次家族令中的“賦”視爲“戶賦”。因此,可將此條文解釋爲“如果兩人以上的成年男性未分異而是同居,則加倍征收戶賦”。所以,可作如下理解:這並不是禁止同居以析出小家庭的政策,而是反映因農業勞動力不足等現實原因,兩名以上的成年男性同居的社會現狀,同時也是爲了公平征收戶賦而制定的政策。通過研究里耶秦簡、嶽麓秦簡中反映的農戶保護政策,究明了爲維持再生産,因勞動力不足等原因農業生産困難的農家選擇同居的情況。另外,也反映出國家也認識到此種社會現象,並實行保護兩人以上成年男性同居家庭的政策。

니트 기법의 섬유조형 작품 연구

변수진 숙명여자대학교 1997 국내석사

Used materials of copper wire, sisalana, electric wire... etc, I had manufactured the work of formative textile arts by knitting technique. After this work , the conclusion that I get is as follows. First, a comprehension of materials is as important as technique. For the harmony of artificial material (copper wire, electric wire) and natural material(sisalana), it have to bring into relief strength after grasping character of materials and complement weakness. Second, for expression of the color sense of variety, it must have been dyed systematic colors by several stages. After this, for effect of natural gradation using several colors, it have to use sisalanas that are different density followed thickness of needles, But this work is very complex and request some patience. Third, the weaknesses of knitting technique are an appearance of curl up and character of fraying. But it bring into relief as strength for natural shape and it is possible to correct by mixed with copper wire. Forth, during keeping, it has some changed of shape by press and this point have to be studied more. The experienced knitting technique getting through a course of formative work of this kind have a possibility of limitless development as a tool of creative expression, getting out of a traditional concept. A case, accompanied analysis and exploitation of new materials, accompanied creative, new and development-oriented pose and continual investigation, the formative textile arts will be shine.

"ISO 10303 AP241: Generic model for lifecycle support of AEC facilities"의 시설물관련 요소의 STEP Modularization에 관한 연구

변수진 경희대학교 대학원 2007 국내석사

The Content and Characteristics of U.S. Enlightenment for Rural Women in Korea in the 1950s and 1960s - Analysis of New Strength

변수진 서울대학교 대학원 2017 국내석사

The purpose of this thesis is to research the enlightenment content that the U.S. wanted to deliver to rural women in Korea by analyzing the magazine New Strength, published by the United States Information Service (USIS) in the 1950s and the 1960s. The analysis reveals four types of representations of women: housewife, member of a democracy, laborer in the sphere of production, and woman leader. Each of the four types has different dimensions, and they are not discrete but rather intricately connected. The categories of housewife and a member of a liberal democracy are naturally assigned to women. Women are commonly represented as housewives because they are biological female, and are represented as members of a democracy because they have political membership like men. Meanwhile, the categories of woman laborer and woman leader are a reflection of a time when women actively participated in the sphere of production. In addition, these two types show how women took part in the sphere of production in accordance with their socio-economic status. Above all, even though four different types of women are represented in the magazine, the magazine has an embedded assumption that rural women are housewives, which corresponds with a prevalent assumption embedded in other international development projects aimed at women at that time. Moreover, it conveys the Westernized modern housewife model as an enlightened model, so content and activities for rural women’s enlightenment mainly deal with household work. This research contributes to filling up the shortage of previous studies on early rural development project in Korea under the guidance of the U.S. aid agency by focusing on gender and promoting a better understanding of rural Korean women’s experiences in the rural development project presented as a best practice model for developing countries.

Improvement of gold catalysts supported by cerium phosphate for oxygen-reduction reaction

변수진 서울대학교 대학원 2013 국내석사

The oxygen-reduction reaction was investigated on gold supported by cerium phosphate in an alkaline electrolyte. The composites with different Au/CePO4 ratios were prepared by co-sputtering. Two-electron reduction of oxygen to hydrogen peroxide has been found with the Au catalysts, while the Au/CePO4 nanocomposite exhibited the four-electron reduction in a same potential region. This enhancement was attributed to the electronic interactions between Au and CePO4, which could be explained by shifting of Au 4f toward lower binding energy. Also, catalytic activity of CePO4 contributed to increase the ORR activity and was confirmed by chronoamperometry. The synergy between Au and CePO4 was unprecedented activity from Au/AlPO4 nanocomposite catalyst.

Synthesis of Ag nanoparticles and mesoporous TiO2 films by PVC-PSSA graft copolymer/ Ag complexes for solar cells

변수진 Graduate School, Yonsei University 2011 국내석사

An amphiphilic graft copolymer consisting of a poly(vinyl chloride) (PVC) backbone and poly(styrene sulfonic acid) (PSSA) side chains (PVC-g-PSSA) was synthesized via atom transfer radical polymerization (ATRP). This polymer electrolyte membrane was ion-exchanged to Ag ions by immersing in 10wt% AgNO3 aqueous solution and templated the growth of Ag nanoparticles by a reducing agent. The formation of Ag nanoparticles was confirmed using UV-visible spectroscopy and X-ray diffraction (XRD). Transmission electron microscopy (TEM) revealed that utilization of NaBH4 was the most effective in the formation of Ag nanoparticles with 10-15 nm in size. The formation of Ag nanoparticles was also strongly affected by the concentration of reducing agent and reduction time. Mesoporous titanium dioxide (TiO2) films with crystalline anatase phase were synthesized via a sol-gel process by templating PVC-g-PSSA graft copolymer. Titanium isopropoxide (TTIP), a TiO2 precursor was selectively incorporated into the hydrophilic PSSA domains of the graft copolymer and grew to form mesoporous TiO2 films, as confirmed by scanning electron microscopy (SEM) and X-ray diffraction (XRD) analysis. The performances of dye-sensitized solar cell (DSSC) were systematically investigated by varying spin coating times and the amounts of P25 nanoparticles. The energy conversion efficiency reached up to 2.7 % at 100 mW/cm2 upon using quasi-solid-state polymer electrolyte.