以多壁奈米碳管修飾奈米TiO2顆粒應用於染料敏化太陽能電池

Application of Multi-wall Carbon Nanotube modified TiO2 nanoparticle to Dye-sensitized Solar Cells

謝東榮(Tung-Jung Hsieh)

指導教授 ： 張合 ； 韓麗龍

國立臺北科技大學/機電學院/製造科技研究所/碩士(2009年)

摘要

本研究使用溶膠凝膠法製備出奈米二氧化鈦顆粒，並進一步將奈米二氧化鈦顆披覆於多壁奈米碳管(MWCNT)上，而製備出TiO2-CNTs奈米複合粉末，以作為染料敏化太陽能電池(DSSCs)中之光電極材料。由於奈米碳管可增加DSSC之短路電流密度(short-circuit current density)，故可有效提升DSSC之光電轉換效率。首先將MWCNT經過酸洗步驟，以去除雜質而提高MWCNT之純度，接下來使用溶膠凝膠法製備出TiO2-CNTs奈米複合粉末，由X-光繞射儀(XRD)之檢測結果顯示，經過450 ℃煅燒處理後中之TiO2，可完全轉變成銳鈦礦(anatase)晶相，另由FE-SEM與TEM顯示TiO2成功的披覆在CNT上。DSSCs中之光電極光製備是使用電泳沉積法(EPD)將Degassa P25 TiO2奈米顆粒混合TiO2-CNT粉末而沉積於ITO導電玻璃上，並經二次電泳沉積得到厚度為14~17 μm之薄膜。最後經光轉換效率的量測實驗結果顯示，添加TiO2-CNTs奈米複合粉末可以增加短路電流密度(Jsc)，使得DSSCs之光轉換效率從原先之3.45 %提升到4.87 %，亦即提高DSSCs之光電轉換效率41 %。

關鍵字

染料敏化太陽能電池 ； 溶膠凝膠法 ； 多壁奈米碳管 ； 奈米二氧化鈦

並列摘要

The study uses sol-gel method to prepare nanoscale titanium dioxide (TiO2), and further applies TiO2 nanoparticle coating on the surface of the multi-wall carbon nanotube (MWCNT). As a result, TiO2-CNT composite nanoparticles are prepared to serve as photoelectrode material in dye-sensitized solar cell (DSSC). For the prepared TiO2-CNT composite nanoparticles, since CNT can increase the shirt-circuit current density of DSSC, the light-to-electricity conversion efficiency of DSSC can be effectively raised. First of all, after MWCNT has gone through acid treatment procedures, impurities are removed to increase the purity of MWCNT. After that, sol-gel method is employed to prepare TiO2-CNT composite nanopowder. As shown from the test results of X-ray diffraction (XRD), after the TiO2 in TiO2-CNT composite nanopowder has been thermally treated under 450oC, it can be completely changed to anatase phase. Besides, as shown from the SEM image, TiO2 has been successfully coated on CNT. The photoelectrode of DSSC is prepared by using electrophoretic deposition method (EPD) to mix the Degassa P25 TiO2 nanoparticles with TiO2-CNT powder for deposition on the indium tin oxide (ITO) conductive glass. After secondary EPD is undergone, a film with thickness 14~17 μm can be acquired. Finally, after the experiment that measures the light-to-electricity conversion efficiency, TiO2 nanoparticles are applied to coat on the MWCNT surface. The photoelectric conversion efficiency of DSSC is increased from the original 3.45 % to 4.87 %, implying that the photoelectric conversion efficiency of DSSC has been increased by as high as 41%.

並列關鍵字

Dye-sensitized solar cells (DSSCs) ； Sol-Gel method ； Multi-wall carbon nanotub(MWCNT) ； TiO2 nanoparticles

參考文獻

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