201039482 六、發明說明. 發明所屬之技術領域 本發明係關於一種染料敏化太陽能電池的光陽電極之 製備方法，尤其有關一種具備奈米碳材7奈米半導體複合材 料之染料敏化太陽能電池光陽電極的製備方法。 先前技術 染料敏化太陽能電池為Gratzel所首先作出來，因此亦 稱為Gratzel cell。染料敏化太陽能電池主要是由光陽電 極、電解質溶液（electrolyte)以及白金（plantium; Pt)對電極 所構成。光陽電極是由一透明的導電玻璃基材例如鑛有 IT0或FTO膜的玻璃基材、形成於該導電玻璃基材的絕緣 表面上的含有Ti〇2粒子的半導體薄膜、及附著於該半導體 薄膜上的染料構成。 台灣專利124 1 029揭示一種染料敏化太陽能電池及其 電極’其中的光陽電極的半導體奈米晶膜被進一步加入有 導電微粒例如金屬粒子及奈米碳材。但此專利揭示之奈米 晶膜中的奈米碳材會因較大的表面能，而形成聚集，且沒 有揭示如何將奈米碳材加入該奈米晶膜之具體方法。至目 前為止，業界仍在持續尋找一種兼具高染料吸附量及高導 電性的染料敏化太陽能電池（DSSCs)光陽電極。 發明内容 本發明的一主要目的在提供一種染料敏化太陽能電池 4 201039482 (DSSCs)之光陽電極光陽電極的製備方法，其中奈米碳材能 夠均勻分散於奈米半導體膜，有助於光陽電極之染料吸附 量’進而提升染料敏化太陽能電池之整體效率。 - 本發明的另一目的在提供一種兼具高染料吸附量及優 - 異的導電性的染料敏化太陽能電池（DSSCs)光陽電極。 為了達成上述發明目的，依本發明内容所完成的一種 染料敏化太陽能電池的奈米半導體複合材料光陽電極之製 備方法，包含下列步驟： Ο a)將官能基化奈米碳材（functi〇naUzed carb〇n nanomaterial)分散於一液態媒體中；b)將二氧化鈦前驅物溶 解或分散於步驟a)所獲得的分散液，其中該二氧化鈦前驅 物對該奈米碳材的重量比為1〇〇〇〇 : 1至1〇〇 : i ; C)於水熱 條件或溶膠-凝膠條件下反應該前驅物，以形成出奈米碳材 /奈米二氧化鈦複合材料膠態溶液；d)再將該奈米碳材/奈米 二氧化鈦複合材料膠態溶液置於高壓釜中於140_350C>C加 ❹熱5-48小時，使得其中的二氧化鈦具有銳鈦礦型；e)將一 聚合物溶液與步驟d)所得到的膠態溶液混合；0濃縮的步 驟e)所得到的膠態溶液與聚合物溶液的混合物；g)將步驟 e)濃縮所得到的漿液塗佈於一導電基材的一絕緣表面上； h)於300-520°C、空氣中煆燒步驟e)塗佈所得到的塗層 10-60分鐘’· i)將步驟…所得到的具有奈米碳材/奈米二氧 化鈦複合材料之塗層的導電基材浸於一染料溶液中，使該 染料附著於該奈米碳材/奈米二氧化鈦複合材料之塗層；及 從該染料溶液中取出該導電基材，而製備出—染料敏化太 5 201039482 %能電池的奈米複合材料光陽電極。 較佳的，步驟a)的官能基化奈米碳材之官能基為酸 基、經基（hydroxyl group)或胺基（amin〇 gr〇up)。更佳的’ 步驟a)的g能基化奈米碳材為酸化單壁、雙壁或多壁破奈 米管，酸化奈米碳角（carbon nanohorn)或酸化奈米碳球 (Carbon nanocapsUles)。最佳的，該官能基化奈米碳材為酸 化單壁、雙壁或多壁碳奈米管。 較佳的，該碳奈米管具有丨_25 μιη的長度，卜5〇 nm的 直徑，15〇-25〇 m2/g的比表面積，長徑比（Aspect rati〇)為 20-2500的多壁碳奈米管。 較佳的，該二氧化鈦前驅物為鈦烷氧化物、四氯化鈦 〇Γ— e — e)、硫酸氧鈦⑹anium。^他⑷或硫酸 鈦（titanium sulfate)。 較佳的，步驟c)係於溶膠_凝膠條件下反應該前驅物。 較佳的，該二氧化鈦前驅物為鈦烷氧化物。更佳的， 該二氧化鈦前驅物為四異丙烷氧化物⑼ tetra-isopropoxide; TTIP) 〇 於溶膠-凝膠條件下，鉍杜& 卜 〒干卜車乂佳的，步驟a)的液態媒體為 醇。更佳的，該液態媒體為里石台 ^ 股局呉丙醇，該異丙醇的重量為奈BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for preparing a photo-positive electrode of a dye-sensitized solar cell, and more particularly to a photo-sensitized solar cell photo-positive electrode comprising a nano-carbon material 7 nano-semiconductor composite material Preparation method. Prior Art Dye-sensitized solar cells were first made by Gratzel and are therefore also known as Gratzel cells. The dye-sensitized solar cell is mainly composed of a photo-positive electrode, an electrolyte solution (electrolyte), and a platinum (plantium; Pt) counter electrode. The photo-anode electrode is composed of a transparent conductive glass substrate such as a glass substrate having an IT0 or FTO film, a semiconductor film containing Ti〇2 particles formed on the insulating surface of the conductive glass substrate, and a semiconductor film attached thereto. The composition of the dye. Taiwan Patent No. 124 1 029 discloses a dye-sensitized solar cell and an electrode thereof. The semiconductor nanocrystalline film of the photo-positive electrode is further added with conductive particles such as metal particles and nano carbon material. However, the nanocarbon material in the nanocrystalline film disclosed in this patent forms aggregate due to the large surface energy, and does not disclose a specific method of how to add the nano carbon material to the nanocrystalline film. Up to now, the industry is still looking for a photo-sensitized solar cell (DSSCs) with high dye adsorption and high conductivity. SUMMARY OF THE INVENTION A primary object of the present invention is to provide a method for preparing a photo-positive electrode photo-positive electrode of a dye-sensitized solar cell 4 201039482 (DSSCs), wherein the nano-carbon material can be uniformly dispersed in the nano-semiconductor film to contribute to the photo-anode electrode The amount of dye adsorption' further increases the overall efficiency of the dye-sensitized solar cell. - Another object of the present invention is to provide a photo-sensitized solar cell (DSSCs) photo-positive electrode which has both high dye adsorption amount and excellent conductivity. In order to achieve the above object, a method for preparing a nano-semiconductor composite photo-anode electrode of a dye-sensitized solar cell according to the present invention comprises the following steps: Ο a) functionalized nano carbon material (functi〇naUzed) The carb〇n nanomaterial) is dispersed in a liquid medium; b) the titanium dioxide precursor is dissolved or dispersed in the dispersion obtained in the step a), wherein the weight ratio of the titanium dioxide precursor to the nano carbon material is 1〇〇〇 〇: 1 to 1〇〇: i ; C) reacting the precursor under hydrothermal conditions or sol-gel conditions to form a colloidal solution of nano carbon/nano titanium dioxide composite; d) The colloidal solution of nano carbon/nano titanium dioxide composite is placed in an autoclave at 140_350 C>C for 5 to 48 hours, so that the titanium dioxide has anatase type; e) a polymer solution and step d The resulting colloidal solution is mixed; 0 is concentrated in step e) to obtain a mixture of the colloidal solution and the polymer solution; g) the slurry obtained by concentrating step e) is applied to an insulating surface of a conductive substrate Upper; h) 300-520 ° C, air calcination step e) coating the obtained coating for 10-60 minutes '· i) Conducting the coating of the nano carbon material/nano titanium dioxide composite obtained by the step... The substrate is immersed in a dye solution to adhere the dye to the coating of the nano carbon material/nano titanium dioxide composite material; and the conductive substrate is taken out from the dye solution to prepare a dye sensitized too 5 201039482% energy battery nano composite photo-optical electrode. Preferably, the functional group of the functionalized nanocarbon material of step a) is an acid group, a hydroxyl group or an amine group (amin〇gr〇up). A better 'step a) g-encapsulated nanocarbon is an acidified single-walled, double-walled or multi-walled nanotube, acidized nano nanohorn or carbon nanocapsUles . Most preferably, the functionalized nanocarbon material is an acidified single wall, double wall or multi-wall carbon nanotube. Preferably, the carbon nanotube has a length of 丨25 μm, a diameter of 5 〇 nm, a specific surface area of 15 〇-25 〇m 2 /g, and an aspect ratio of 20-2500. Wall carbon nanotubes. Preferably, the titanium dioxide precursor is titanium alkoxide, titanium tetrachloride 〇Γ-e-e), titanium oxysulfate (6) anium. ^He (4) or titanium sulfate. Preferably, step c) is to react the precursor under sol-gel conditions. Preferably, the titanium dioxide precursor is a titanium alkoxide. More preferably, the titanium dioxide precursor is tetraisopropoxide oxide (9) tetra-isopropoxide; TTIP) 溶胶 under sol-gel conditions, 铋杜 & 卜〒干布车乂佳, the liquid medium of step a) is alcohol. More preferably, the liquid medium is Lishitai ^ 呉 呉 呉, the weight of the isopropyl alcohol is Nai
米碳材重量的200-1200%，光B 並且该分散係於超音波處理下 進行。 較佳的，步驟b)將二ϋ , 氧化鈦則驅物溶解或分散於步驟 a)所獲得的分散液係於超音波處理下進行。 較佳的，該溶膠-凝膠你彼 /怿件下反應该m驅物包含將水加 201039482 入步驟b)所獲得的混合物及使該鈦烷氧化物進行水解及縮 合反應。更佳的，該溶膠-凝膠條件下反應該前驅物進一步 包含將酸加入該水解及縮合反應混合物。最佳的，水被加 • 入的重量為奈米碳材重量的100-1000%，及該酸被加入的 量為使該水解及縮合反應混合物的pH值為1 -5。 較佳的’於步驟d)的高壓釜的溫度為15〇_3〇〇Qc，及 加熱時間為10-30小時。 較佳的，該導電基材為其一表面具有一導電層的導電 U玻璃。 較佳的’步驟e)的聚合物溶液為一具有重量分子量為 200〜30000 g/mol之聚合物的水溶液。更佳的，該聚合物為 聚多7醇（polyol)、環糊精（cyclodextrin)或纖維素 (cellulose)。 較佳的，該聚合物為聚乙二醇、聚丙二醇或聚丁二醇。 更佳的，該聚合物為聚乙二醇。 Ο 較佳的’步驟e)的濃縮至該混合物為每公升含有 1〇〇_250 g固體成份的漿液。 較佳的，步驟g)的塗佈係以刮刀法進行。 本發明中該官能基化奈米碳材的添加量的一合適例子 為0.1-0.5 wt%，較佳的，0.3至0.5 wt%，以整體奈米半導 體複合材料的重量為基準。。 本發明的一具體實施例使用0.1 wt%的酸化多壁碳奈 米管’所製備出之染料敏化太陽能電池奈米半導體複合材 料光陽電極，其染料吸附量為9 62 X 1〇-8 m〇i/cm2 ;電池開 7 201039482 路電壓（〇pen_circuit Photovoltage; Foc)為 ο. V;短路電 流（Sh〇rt-Circuit Photocurrent density ·，為 7 73 mA/cm-2 ; 填充因子（而—*;1717)7〇12%;及染料敏化太陽能電池 轉換效率為3.75%。 本發明的另一較佳具體實施例使用0.5 wt%的酸化多 壁碳奈米管，所製備出之染料敏化太陽能電池奈米半導體 複合材料光陽電極，其染料吸附量為116 χ 1〇_7m〇1/cm2 ; k 為 0.74V; ‘為 7 91mA/cm-2;汀為 72 i7%;染料敏 化太陽能電池轉換效率為4·22%。。 本發明的又一較佳具體實施例使用0.3 wt%的酸化多 壁碳奈米管，所製備出之染料敏化太陽能電池奈米半導體 複合材料光陽電極，其染料吸附量為132 X Μ ; 〇c 為 0.72 V ’ Jsc 為 8 82 mA/cm 2 ; FF 為 ;染料敏 化太陽能電池轉換效率為4·62〇/〇。 實施方式 本發明揭示一種形成於導電玻璃基材的絕緣表面上的 奈米碳材/奈米半導體複合材料之製備方法，其具有高染料 吸附里並具有較高的染料敏化太陽能電池之轉換效率。因 此，本發明彳法所製作出的《陽電⑯，對於染料敏化太陽 能電池具有應用價值。 本發明將藉由下列實施例被進一步了解，該等實施例 僅作為說明之用，而非用於限制本發明範圍。 於下列的實施例及對照例中使用以下的鈦四異丙烷氧 201039482 化物（titanium tetra-isopropoxide ; ΤΤΙΡ)，酸化之多壁碳奈 米管及聚乙二醇 20000 (polyethylene glycol 20000; PEG 20000)： ' 欽四異丙烧氧化.物：Titanium tetra-isoproxide (ΤΤΪΡ) ’ 其分子量為 284.26 g/mole，購自八1(11^11(：〇.，81 Louis, MO., U.S.A. ° 多壁碳奈米管（MWCNTs): Ctube100，韓國 CNT CO., ^ LTD·，奴奈米官長度為i_25 μηι，直徑為10-50 nm，比表面 〇 也 2 積為 150-250 m /g，長徑比（Aspect ratio)為 20-2500 m2/g。 多壁碳奈米管在使用前，先進行酸處理，即是利用傳 統的硝酸酸洗法。取8 g奈米碳管及硝酸400 ml置於、三頸 瓶中，以120°C進行酸化迴流，反應時間為8 hr，待反應結 束後，以大量純水中止反應，經五次的水洗抽氣過濾，且 於烘箱70°C下烘乾，即可得到酸化多壁碳奈米管。酸洗後 的多壁碳奈米管於穿透式電子顯微鏡中發現原多壁碳奈米 〇 管所含的雜質被有效的除去’且在FT-IR光譜中發現其表 面與文獻中報導的類似具有_C = 〇 (1167 cm·1)及-COO (1702 cm_1)官能基。 染料：分子量為1 1 88.55 g/mole，商品名為N719， Solaronix SA Co. (Aubonne, Switzerland)生產。 201039482 Θ »The weight of the carbonaceous material is 200-1200%, the light B and the dispersion is carried out under ultrasonic treatment. Preferably, step b) dispersing or dispersing the diterpene, titanium oxide precursor in the dispersion obtained in step a) is carried out under ultrasonic treatment. Preferably, the sol-gel reaction of the m-driver comprises adding water to 201039482 to the mixture obtained in step b) and subjecting the titanium alkoxide to hydrolysis and condensation. More preferably, reacting the precursor under the sol-gel condition further comprises adding an acid to the hydrolysis and condensation reaction mixture. Most preferably, the water is added in an amount of from 100 to 1000% by weight based on the weight of the nanocarbon material, and the acid is added in an amount such that the hydrolysis and condensation reaction mixture has a pH of from 1 to 5. Preferably, the autoclave at step d has a temperature of 15 Å to 3 Torr Qc and a heating time of 10 to 30 hours. Preferably, the conductive substrate is a conductive U glass having a conductive layer on one surface thereof. The preferred 'step e) polymer solution is an aqueous solution having a polymer having a weight molecular weight of from 200 to 30,000 g/mol. More preferably, the polymer is a polypolyol, cyclodextrin or cellulose. Preferably, the polymer is polyethylene glycol, polypropylene glycol or polytetramethylene glycol. More preferably, the polymer is polyethylene glycol.较佳 Preferred 'Step e) is concentrated until the mixture is a slurry containing 1 〇〇 250 g of solids per liter. Preferably, the coating of step g) is carried out by a doctor blade method. A suitable example of the amount of the functionalized nanocarbon material to be added in the present invention is from 0.1 to 0.5% by weight, preferably from 0.3 to 0.5% by weight, based on the total weight of the nano-semiconductor composite. . A specific embodiment of the present invention uses a 0.1 wt% acidified multi-walled carbon nanotube tube to prepare a dye-sensitized solar cell nano-semiconductor composite photo-positive electrode with a dye adsorption amount of 9 62 X 1 〇 - 8 m 〇i/cm2 ; battery open 7 201039482 road voltage (〇pen_circuit Photovoltage; Foc) is ο. V; short circuit current (Sh〇rt-Circuit Photocurrent density ·, 7 73 mA/cm-2; fill factor (and —* 1717) 7〇12%; and dye-sensitized solar cell conversion efficiency of 3.75%. Another preferred embodiment of the present invention uses 0.5 wt% acidified multi-wall carbon nanotubes to prepare dye sensitization The solar cell nano-composite photo-positive electrode has a dye adsorption capacity of 116 χ 1〇_7m〇1/cm2 ; k is 0.74V; ' is 7 91mA/cm-2; Ting is 72 i7%; dye-sensitized solar energy The battery conversion efficiency is 4.22%. Another preferred embodiment of the present invention uses a 0.3 wt% acidified multi-wall carbon nanotube to prepare a dye-sensitized solar cell nano-semiconductor composite photo-positive electrode. The dye adsorption capacity is 132 X Μ ; 〇c is 0.72 V ' Jsc is 8 82 m A/cm 2 ; FF is; dye-sensitized solar cell conversion efficiency is 4.62 〇 / 〇. Embodiments The present invention discloses a nano carbon material / nano semiconductor composite material formed on an insulating surface of a conductive glass substrate The preparation method has the advantages of high dye adsorption and high conversion efficiency of the dye-sensitized solar cell. Therefore, the "Yangdian 16" produced by the method of the invention has application value to the dye-sensitized solar cell. The following examples are further understood to be illustrative, and are not intended to limit the scope of the invention. The following titanium tetraisopropane oxygen 201039482 (titanium) is used in the following examples and comparative examples. Tetra-isopropoxide; ΤΤΙΡ), acidified multi-walled carbon nanotubes and polyethylene glycol 20000 (polyethylene glycol 20000; PEG 20000): 'Chin tetraisopropoxide oxidation: Titanium tetra-isoproxide (ΤΤΪΡ)' 284.26 g/mole, purchased from 八1(11^11(:〇.,81 Louis, MO., USA ° multi-walled carbon nanotubes (MWCNTs): Ctube100, Korean CNT CO., ^ LTD·, slave Official meter length i_25 μηι, a diameter of 10-50 nm, specific surface area of 2 square is also an inner volume of 150-250 m / g, an aspect ratio (Aspect ratio) of 20-2500 m2 / g. Multi-walled carbon nanotubes are acid treated prior to use, using conventional nitric acid pickling. Take 8 g of carbon nanotubes and 400 ml of nitric acid in a three-necked flask, and acidify and reflux at 120 ° C for 8 hr. After the reaction is completed, the reaction is stopped in a large amount of pure water and washed five times. The oil is filtered and dried in an oven at 70 ° C to obtain an acidified multi-wall carbon nanotube. The acid-washed multi-walled carbon nanotubes were found to have been effectively removed by the transmission electron microscopy in the original multi-walled carbon nanotubes. The surface was found in the FT-IR spectrum and reported in the literature. Similar to having _C = 〇 (1167 cm·1) and -COO (1702 cm_1) functional groups. Dye: Molecular weight 1 1 88.55 g/mole, trade name N719, Solaronix SA Co. (Aubonne, Switzerland). 201039482 Θ »
Bu4N ㊀。〇Bu4N one. 〇
‘八'Eight
Bu4N 聚乙二醇20000 (PEG 20000):重量平均分子量為 20000 g/mole，商品名為 U204-07，Mallinckrodt Baker，Inc. 生產。Bu4N Polyethylene Glycol 20000 (PEG 20000): Weight average molecular weight 20000 g/mole, trade name U204-07, manufactured by Mallinckrodt Baker, Inc.
異丙醇：isopropyl alcohol，其分子量為 60.1 g/mole， 購自 Aldrich Co·，St· Louis，MO., U.S.A.。 導電玻璃板（transparent conducting oxide, TCO):購自Isopropanol: isopropyl alcohol having a molecular weight of 60.1 g/mole, available from Aldrich Co., St. Louis, MO., U.S.A. Transparent conducting oxide (TCO): purchased from
Asahi Glass Co.，Japan 的 FTO 導電玻璃。 實施例A1-A3 : 奈米複合材料光陽電極之製備 1 ·以表1所示之比例將酸化多壁碳奈米管添加於6〇 mi無 10 201039482 水異丙醇。FTO conductive glass from Asahi Glass Co., Japan. EXAMPLES A1-A3: Preparation of Nano Composite Photoreceptor Electrode 1 - Acidified multi-walled carbon nanotubes were added to 6 〇 mi without 10 201039482 water isopropanol at the ratios shown in Table 1.
0-0064 (0.1〇/〇) 0-0192 (0.3〇/〇) 〇·〇320 (〇 5〇/n) wt% = MWCNTs 重量 /(MWCNTs 重量 + Ti〇2 重量）0-0064 (0.1〇/〇) 0-0192 (0.3〇/〇) 〇·〇320 (〇 5〇/n) wt% = MWCNTs Weight / (MWCNTs Weight + Ti〇2 Weight)
於超音波震盡下將酸化多壁礙奈米管均句分散於無水異 丙醇中接著中再加入23.5 g (8〇 mm〇ie)的鈦四異丙烧 氧化物TTIP)，並持續超音波震盛3〇分鐘。將混合均句 的酸化多壁碳奈米管/鈦四異丙烷氧化物/異丙醇溶液緩 慢倒入含有150 ml去離子水的燒杯中並劇烈攪拌，再以 69%硝酸將混合物的？]^值調整至1.8，並加熱至8〇。匸， 持溫8小時。加熱過程中，異丙醇將會被完全蒸出來， 最後可得約130 ml的酸化多壁碳奈米管/二氧化鈦膠態 水溶液。 2.反應完成後，將該多壁碳奈米管/二氧化鈦膠態水溶液置 入高壓爸中，並於烘箱中以2〇〇〇c加熱12小時，而待 溶液冷部後，可得多壁碳奈米管/銳鈦礦型二氧化鈦膠態 水溶液。 3.將2.644 g的40 wt%的聚乙二醇2〇〇〇〇水溶液加入前述 夕壁石反奈米官/銳鈦礦型二氧化鈦膠態水溶液，並劇烈攪 掉小時。爾後將所獲得的約13 0 ml的混合物減壓濃縮 201039482 成每公升溶液中含 液，接著利㈣刀、=§複合材料的高黏度漿 絕緣蛊“ 得的漿液塗在FTO導電破璃的 ，塗佈出來的有效面積為〇25⑽2。 =二時後，置於峨、空氣中锻燒％分鐘： 行“之不、米半導體複合材料光陽電極基材。 4.爾後將製作好的太半主道μ &入 ^ 的不未+導體複合材料光陽電極基材於室 皿下保存在3xlG 4 M的N7i9染料溶液中小時， 之後再將吸附有染料之奈米半導體複合材料光陽電極基 材保存於酒精中6·15小時將多餘的染料脫附。該N719 染料溶液係順-二硫氰胺_N，N，_雙（二吡啶基_4_羧酸_4，_ 季 丁基銨 羧酸釕 （π) 鹽 (CiS-dithi〇Cyanato_N，N，_bis(2,2,_bipyridyl4_carb〇xyiica cid-4'-tetrabutyl ammonium carboxylate) ruthenium (II)) 於丙烯腈/第三丁醇體積比1:1的混合溶劑中 (acetonitride/t-butyl alcohol (V：V = 1:1)) ° 對照例： 除了不使用酸化多壁碳奈米管及超音波震盪外，重覆 實施例A1-A3的步驟。 染料吸附量 測試方法： 為了比較染料吸附量與光電極粗縫度，事先將製備出 來的光電極浸泡入3 X 1 0_4 Μ的N7 1 9染料溶液1 0-24小時， 12 201039482 再將吸附於光電極上的染料置入〇1Μ氫氧化鉀水溶液中 脫附之，再透過UV-可見光光譜（CARY 50 Cone, Variant 吸收度（absorbance, a)，利用式一來得知染料吸附量。 ' a = ε X b X c (式一） 式一中之a表示材料吸收特定波長的能力、ε為莫爾消 光係數（molar extinction coefficient (ε), cm2/mole)、b 為光 路徑（1 cm) ’而c則代表染料溶液的莫爾濃度。所測得的染 料吸附量被列於表2。 表2 樣品 染料吸附量 (mole/cm2) A1 9.62 X 1〇'8 A2 1.32 > 【10·7 A3 1.1 6 > [10'7 對照例 8.66X10'8 〇 理淪上，較粗糙的表面型態與較多空孔的二氧化鈦半 導體層可反映出較高的染料吸附值。因此可以利用表面粗 糙因子的改變來探討添加碳奈米管對二氧化鈦光陽電極表 面的形態特徵的影響，如圖i所示。圖i中，粗糙因子主 要疋利用該二氧化鈦光陽電極對於染料（N7丨9)之吸附能 力，再以每個N719染料分子為nm2之表面積數據計算 出每個光陽電極的粗糙因子，其單位為每單位半導體材 料薄膜面積之比表面積（cm2/cm2)。計算粗糙因子數值之公 式如式二所示： 13 201039482 、 Dad x Na x DA=Rf (式二） 式二中之Dad表示材料的單位面積染料吸附莫耳數、 ΝΑ為亞佛加厥數、Da為每個染料分子面積（16 ·2)，而 1則代表粗链因子數值。理論上二氧化鈦光陽電極吸附染 料分子主要是形成單層染料單分子層（mono_layer);因此， 染料吸附含量可直接表達出電極材料之單位表面積。若電 極吸附了較多的染料分子即表示該電極表面與内部應是處 於較粗糙且多孔洞的形態。因此，由圖丨可以明顯發現到’ 當碳奈米管添加含量由〇wt%增加到〇 3 wt%，電極的粗糙 因子數值由834上升至！ 267，這個現象說明了添加碳奈米 官確實可增加電極的粗糙因子數值（可吸附染料的表面 積）。 再者，電極具有較粗糙的表面型態，可增加電極與電 解液間的接觸面積，亦可提升光誘導電子傳輸過程的效 率’因此，可增加太陽能電池的光電轉換效率。 入射光子轉換效率（Incident Photon conversion to charge carrier Conversion Efficiency (IPCE)) 測試方法： 光電流-電壓特性則是透過恆電位儀在AM 1_5、照度 100 mW/cm2 ( Oriel )的光照下測量而得的。固定波長照光 下的光電流-波長測試則是透過在染料敏化太陽能電池及 光源（100 mW/cm2)間放置含自動過濾裝置的單光器 (Monochromatic; Sciencetech Model 9030)而測得。不同光 14 201039482 波長T射下所對應的光電流分別記錄之，最後再利用公式 二計算而得到入射光子轉換效率（IPCE)的圖譜。 IPCE{%) = \2AQJs〇 .· λ?ίη (式二） • 式二中】sc代表短路電流，人為入射光波長（從400到8〇() nm) ’而pin則代表入射光功率。 圖2示出以對照例及實施例A1_A3得到之光陽電極所 0 組裝的染料敏化太陽能電池之單一波長的IPCE圖譜。從圖 2可以很明顯看見，當碳奈米管含量增加時（由〇增加至〇3 wt%) ’其ipce的強度也會大幅提升，此結果可以歸諸於：（1) 染料吸附量的提升；（2)由於添加碳奈米管導致有較高的光 誘導電子驅動能力；（3)染料敏化太陽能電池元件的電荷再 復合效率降低。 然而，當碳奈米管的添加含量較高時（0.5 wt°/〇)，其 IPCE之強度值卻有下降的情形，相較於碳奈米管添加含量 〇 較低（0-0.3 wt%)之IPCE數值趨勢是較不同的。由於碳奈米 管本身具有可吸收較高光波長能量的能力（> 400 nm)，而一 般二氧化鈦材料卻只可吸收較低光波長能的特性（< 400 nm)。因此，當染料敏化太陽能電池照光發電時，過多的碳 奈米管存在應會造成染料分子之光捕獲能力受到抑制，因 而限制了該太陽能電池之光電流行為。由該現象可知，在 染料敏化太陽能電池之光陽電極中’最佳的碳奈米管添加 量應為0.3 wt°/〇。根據上述測試結果，可以推斷出於Ti02 合成過程中添加多壁破奈米管是一種有效提升染料敏化太 15 201039482 陽能電池之光電轉換效率的方法。 染料敏化太陽能電池之性能測試 測試方法： 染料敏化太陽能電池性能測試是在AM L 5的模擬太 陽光照射下進行。 圖3表示了以對照例及實施例APA3得到之光陽電極 所組裝的染料敏化太陽能電池所呈現的光電流密度-電壓 (J-V)曲線。表3列出了以對照例及實施例A1-A3得到之光 陽電極所組裝的染料敏化太陽能電池的開路電壓（p〇c)、短 路電流（/sc)、填充因子（fill factor, F.F·)及光電轉換效率 (η)。很明顯地，當碳奈米管含量從0增加到〇 5 wt%時， 太陽能電池的短路電流（《/sc)由5.97上升至8 82 mA/em: (0-0.3 wt%) ’但於碳奈米管含量較高時（〇 5糾％)卻下降至 7_91 ma/cm2 ;另外，開路電麗（F〇c )亦從0·65上升至〇<74 V，填充因子（fill factor，F.F.)則維持在〜72〇/〇左右。染料敏 化太陽能電池的光電轉換效率（η )，如矣^ μ _ \ u文衣3所不由2_87 % (對 照例）上升約61%到4.62% (A2)，但其後又些微下降至 4.22% (A3) 〇 ---------通言夕壁碳奈 管的導入，電池表現出之開路電壓及短路電流將會隨之 所變動’而太陽能電池的整體光電轉換效率⑷也將明顯 受這些性質影響。 201039482 表3 V〇c (V) 對照例 0.65 A1 0.69 A2 0.72 A3 0.74After the ultrasonic wave is shaken, the acidified multi-walled tube is dispersed in anhydrous isopropanol, and then 23.5 g (8〇mm〇ie) of titanium tetraisopropyl oxide (TTIP) is added, and the ultra-continuation is continued. The sound wave is shaking for 3 minutes. Slowly pour the acidified multi-walled carbon nanotube/titanium tetraisopropoxide oxide/isopropanol solution into a beaker containing 150 ml of deionized water and stir vigorously, then mix the mixture with 69% nitric acid. The value of ^ is adjusted to 1.8 and heated to 8 〇. Hey, hold the temperature for 8 hours. During the heating process, the isopropanol will be completely distilled off, and finally about 130 ml of the acidified multi-walled carbon nanotube/titanium dioxide colloidal aqueous solution can be obtained. 2. After the reaction is completed, the multi-walled carbon nanotube/titanium dioxide colloidal aqueous solution is placed in a high pressure dad and heated in an oven at 2 〇〇〇c for 12 hours, and after the cold portion of the solution, the wall is more Carbon nanotube / anatase type titanium dioxide colloidal aqueous solution. 3. 2.644 g of a 40 wt% aqueous solution of polyethylene glycol 2 hydrazine was added to the aforementioned smectite anti-nanoporous/anatase-type titanium dioxide colloidal aqueous solution, and vigorously stirred for hours. Then, about 130 ml of the obtained mixture is concentrated under reduced pressure into 201039482 to form a liquid per liter of solution, and then the high-viscosity slurry of the (four) knife, =§ composite material is applied to the FTO conductive glass. The effective area coated is 〇25(10)2. = After 2 hours, it is placed in helium and air forging for 5% minutes: "No", rice semiconductor composite photo-optical electrode substrate. 4. After that, the fabricated semi-main track μ & not included + conductor composite photo-optical electrode substrate is stored in a 3xlG 4 M N7i9 dye solution under the chamber for a few hours, after which the dye is adsorbed. The nano-semiconductor composite photo-optical electrode substrate is stored in alcohol for 6.15 hours to desorb excess dye. The N719 dye solution is cis-dithiocyanamide_N,N,_bis(dipyridyl-4-carboxylic acid_4,_ quaternary butyl ammonium carboxylate (π) salt (CiS-dithi〇Cyanato_N, N, _bis 2 th bi ace ace = 1:1)) ° Comparative Example: Repeat the procedure of Examples A1-A3 except that acidified multi-walled carbon nanotubes and ultrasonic vibration are not used. Dye adsorption amount test method: In order to compare dye adsorption amount with photoelectrode For the roughness, the prepared photoelectrode was previously soaked in a 3 X 1 0_4 ΜN7 19 dye solution for 10-24 hours, 12 201039482. The dye adsorbed on the photoelectrode was placed in a 〇1Μ potassium hydroxide aqueous solution. In addition, through the UV-visible spectrum (CARY 50 Cone, Variant absorbance (a), the dye adsorption amount is known by the formula 1. ' a = ε X b X c (Formula 1) The ability of a material to absorb a specific wavelength, ε is the molar extinction coefficient (ε), cm2/mole b is the light path (1 cm)' and c is the molar concentration of the dye solution. The measured dye adsorption amounts are listed in Table 2. Table 2 Sample dye adsorption amount (mole/cm2) A1 9.62 X 1〇 '8 A2 1.32 > [10·7 A3 1.1 6 > [10'7 Comparative Example 8.66X10'8 On the ruthenium, the coarser surface type and more porous titanium dioxide semiconductor layer can reflect higher The dye adsorption value. Therefore, the influence of the surface roughness factor can be used to investigate the effect of adding carbon nanotubes on the morphological characteristics of the surface of the titanium dioxide photo-positive electrode, as shown in Fig. i. In Figure i, the roughness factor is mainly used to utilize the titanium dioxide photo-positive electrode. For the adsorption capacity of the dye (N7丨9), the roughness factor of each photo-anode electrode is calculated by using the surface area data of each N719 dye molecule as nm2, and the unit is the specific surface area (cm2/cm2) of the film area per unit semiconductor material. The formula for calculating the value of the roughness factor is as shown in Equation 2: 13 201039482 , Dad x Na x DA=Rf (Formula 2) Dad in Formula 2 represents the dye adsorption molar number per unit area of the material, and the ΝΑ is the Yafot number Da for each dye Molecular area (16 * 2), and a thick chain factor values represent. Theoretically, the TiO 2 photo-anoe electrode adsorbs dye molecules mainly to form a monolayer dye monolayer (mono_layer); therefore, the dye adsorption content can directly express the unit surface area of the electrode material. If the electrode adsorbs more dye molecules, it means that the surface and inside of the electrode should be in a rough and porous form. Therefore, it can be clearly seen from the figure that when the carbon nanotube addition content is increased from 〇wt% to 〇3 wt%, the roughness factor value of the electrode rises from 834 to! 267, this phenomenon shows that the addition of carbon nanotubes does increase the roughness factor of the electrode (the surface area of the adsorbable dye). Furthermore, the electrode has a rough surface type, which increases the contact area between the electrode and the electrolyte, and also improves the efficiency of the photoinduced electron transport process. Therefore, the photoelectric conversion efficiency of the solar cell can be increased. Incident Photon conversion to charge carrier conversion efficiency (IPCE) test method: The photocurrent-voltage characteristic is measured by a potentiostat under the illumination of AM 1_5 and illumination of 100 mW/cm 2 ( Oriel ). . The photocurrent-wavelength test at fixed wavelength illumination was measured by placing a monochromator (Monochromatic; Sciencetech Model 9030) with an automatic filter between the dye-sensitized solar cell and the light source (100 mW/cm2). Different light 14 201039482 The photocurrent corresponding to the wavelength T is recorded separately, and finally the equation of the second method is used to obtain the map of the incident photon conversion efficiency (IPCE). IPCE{%) = \2AQJs〇 .· λ?ίη (Formula 2) • In Equation 2, sc represents the short-circuit current, the wavelength of the incident light (from 400 to 8 〇() nm) and the pin represents the incident light power. Fig. 2 shows an IPCE spectrum of a single wavelength of a dye-sensitized solar cell assembled with a photo-positive electrode obtained in Comparative Example and Example A1_A3. It can be clearly seen from Fig. 2 that when the content of carbon nanotubes increases (from 〇 to wt3 wt%), the strength of ipce will also increase significantly. This result can be attributed to: (1) the amount of dye adsorption (2) High light-induced electron drive capability due to the addition of carbon nanotubes; (3) Reduced charge recombination efficiency of dye-sensitized solar cell elements. However, when the carbon nanotubes are added at a higher level (0.5 wt ° / 〇), the strength of the IPCE is decreased, compared to the carbon nanotubes, the content is lower (0-0.3 wt%). The IPCE value trend is quite different. Since the carbon nanotubes themselves have the ability to absorb higher wavelengths of light energy (> 400 nm), conventional titanium dioxide materials can only absorb properties of lower wavelengths of light (< 400 nm). Therefore, when the dye-sensitized solar cell is used for photovoltaic power generation, the presence of excessive carbon nanotubes should cause the light-trapping ability of the dye molecules to be suppressed, thereby limiting the photocurrent behavior of the solar cell. From this phenomenon, it is understood that the optimum amount of carbon nanotubes added in the photo-positive electrode of the dye-sensitized solar cell should be 0.3 wt ° / 〇. According to the above test results, it can be inferred that the addition of multi-walled nanotubes during the TiO2 synthesis process is a method for effectively improving the photoelectric conversion efficiency of the dye-sensitized solar cell. Performance test of dye-sensitized solar cells Test method: The dye-sensitized solar cell performance test was carried out under simulated sunlight of AM L 5. Fig. 3 is a graph showing the photocurrent density-voltage (J-V) curve exhibited by the dye-sensitized solar cell assembled in the comparative example and the photo-positive electrode obtained in Example APA3. Table 3 lists the open circuit voltage (p〇c), short-circuit current (/sc), and fill factor (fill factor) of the dye-sensitized solar cell assembled with the photo-positive electrode obtained in the comparative example and the examples A1-A3. And photoelectric conversion efficiency (η). Obviously, when the carbon nanotube content increases from 0 to 〇5 wt%, the short-circuit current of the solar cell ("/sc) rises from 5.97 to 8 82 mA/em: (0-0.3 wt%) 'but When the content of carbon nanotubes is high (〇5=%), it drops to 7_91 ma/cm2; in addition, the open circuit (F〇c) also rises from 0·65 to 〇<74 V, fill factor , FF) is maintained at ~72〇/〇. The photoelectric conversion efficiency (η ) of the dye-sensitized solar cell, such as 矣^ μ _ \ u, was not increased by about 61% to 4.62% (A2), but decreased slightly to 4.22. % (A3) 〇---------Introduction of the introduction of the carbon nanotubes on the wall, the open circuit voltage and short-circuit current of the battery will change accordingly' and the overall photoelectric conversion efficiency of the solar cell (4) Will be significantly affected by these properties. 201039482 Table 3 V〇c (V) Comparative Example 0.65 A1 0.69 A2 0.72 A3 0.74
圖式簡單說明 圖1碳奈米一氧化鈦光陽電極之表面粗縫因子，其 申水平軸代表碳奈米管的用量及垂直軸代表粗糙因子數 值。 圖2示出以對照例及實施例A1_ A 3得到之光陽電極所 組裝的染料敏化太陽能電池之單一波長的入射光子轉換效 率（IPCE)。 Η 3表系了以對照例及實施例A1 _A3得到之光陽電極 μ敏化太陽能電池所呈現的光電流密度-電壓 所組裝的染料私 (J-V)曲線。 17BRIEF DESCRIPTION OF THE DRAWINGS Fig. 1 The surface roughing factor of the carbon nano-TiO 2 photo-positive electrode, whose horizontal axis represents the amount of carbon nanotubes and the vertical axis represents the roughness factor. Fig. 2 shows the incident photon conversion efficiency (IPCE) of a single wavelength of the dye-sensitized solar cell assembled by the photopositive electrode obtained in the comparative example and the examples A1 to A3. The Η 3 shows the dye-specific (J-V) curve of the photocurrent density-voltage exhibited by the photo-positive electrode sensitized solar cell obtained in Comparative Example and Example A1_A3. 17