二氧化鈦奈米柱及其碳修飾於光電化學分解水產氫之應用

Applications of TiO2 Nanorods and Their Carbon Decoration in Photoelectrochemical Water Splitting for Hydrogen Production

朱家甫(Chu, Chia Fu)

指導教授 ： 呂世源

國立清華大學/工學院/化學工程學系/碩士(2015年)

摘要

本研究使用簡易且低成本之水熱法，分別以四氯化鈦和異丙醇鈦為前驅物，透過升溫速度10oC/min的條件，以及持溫溫度180~200oC下反應2.5~12小時，成功製備一維二氧化鈦奈米柱於FTO基板上，其經過X光繞射光譜後驗證為金紅石晶型，並能以濃度參數控制其奈米柱直徑大小及其生長能力。其奈米柱從FTO的導電表面垂直向上生長，並以一根一根的小結構柱聚集成直徑約120nm之大奈米柱。經過實際測試，在一個太陽光的強度照射下，其光電流密度約為0.70mA/cm¬2，以未加偏壓下的光電轉換效率值即擁有0.59%的高效能值，經過一小時照光仍舊維持保有77.6%的光電流密度。
其次在二氧化鈦奈米柱上以碳系列材料修飾，如葡萄糖、己二酸和氧化石墨烯，運用碳的包覆層形成異質結構於一維二氧化鈦奈米柱表面，增進電子傳導能力，減少電子和電洞再結合機率，使二氧化鈦光觸媒提升其效能。本研究已成功使用水熱及鍛燒法分別製備這三種修飾於二氧化鈦奈米柱的成品。以前驅物同時加入葡萄糖和後續以己二酸浸泡的成品，其光電流密度值提升至1.00mA/cm2，光電轉換效率達至0.70%。而使用氧化石墨烯作為碳修飾的成品效果表現最佳，光電流密度高達1.04mA/cm2，足足相對純二氧化鈦奈米柱提升了30%的表現。且在不施加偏壓時，其光電轉換效率值即可擁有0.88%的高效能值，經過一小時照光仍舊維持保有72.5%的光電流密度，成功使此修飾材料達到更高的光電化學能力表現。

關鍵字

二氧化鈦 ； 碳修飾 ； 奈米柱 ； 光電化學

並列摘要

In this research, we use a simple and low cost hydrothermal method for producing one dimensional titanium dioxide on FTO substrates. Using titanium tetrachloride or titanium isopropoxide as the precursor heated up with a 10 oC/min heating rate up to 180-200 oC for 2.5-12 hours, we successfully produced one dimensional titanium dioxide rod clusters with an average diameter of 120 nm, and its structure is proven to be rutile via X-ray diffraction. It gives 0.70 mA/cm2 in saturation current density under AM1.5G solar exposure, the applied bias photon effiency reaches 0.59%, and the efficiency retention is maintained at 77.6% after 1 hour operation
Also, other compounds containg carbon are decorated onto the surface of the titanium nanorods for enhancing their PEC water splitting performances. For building a heterojunction structure to help electrons transfer to FTO substrate and improving efficiency of titanium dioxide, we decorate some carbon compounds such as glucose, adipic acid and reduced graphene oxide. Good performances are collected by using glucose as the precursor and adipic acid as the decorating carbon material, with a saturation current density up to 1.00 mA/cm2, the applied bias photon effiency reaches 0.70%. Best performances are collected by using reduced graphene oxide as the decorating carbon material, with a saturation current density up to 1.04 mA/cm2, 30% improvement as compared to pure titanium dioxide nanorods. The applied bias photon effiency reaches 0.88%, and the efficiency retention is maintained at 72.5% after 1 hour operation.

並列關鍵字

TiO2 ； nanorod ； carbon ； photoelectrochemical

參考文獻

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