設計與製造金屬氧化物應用在光電化學分解水與超電容

光電化學分解水是具有前瞻性的再生能源技術。它可以直接將太陽能轉換成可儲存和乾淨的燃料，氫氣。然而，光電化學分解水的光-氫轉換效率仍然不高(< 1%)，主要是因為光陽極無法產生足夠的光伏和光電流。清楚的瞭解電洞的介穩態費米能階在能帶中的形貌可以預測光伏和光電流。這篇論文中，將透過水溶液成長金屬氧化物奈米線作為光陽極來檢測光電化學分解水的特性。本研究著重在(i)計算光陽極材料的電洞濃度、(ii)建構一系列隨偏壓變化的能帶圖來總結光電流產生的原因、以及(iii)透過後置熱處理來降低鈦摻雜氧化鐵的電洞傳導和傳遞電阻以增進光水解表現。除了再生能源的產生，能量的儲存也日漸重要。超電容是一種具有前瞻性的儲能技術。它可以在幾秒內快速的充放電，因此可以提供電動車瞬間的爆發力。超電容的瓶頸在於成本過高，尋求低成本高能量密度的超電容材料是發展重點。二氧化錳是一個具有潛力的超電容材料因為低成本和高理論電容值。但是他本身的載子傳導限制其超電容的表現，本論文透過高表面積、高導電度的二氧化錳奈米柱當作電纜，提供二氧化錳本身缺乏的電荷傳導性，其電容值表現在1 M Na2SO4，掃描速度2mV s-1，可達到793 F g-1。

關鍵字

金屬氧化物；光電化學分解水；超電容

並列摘要

Photoelectrochemical (PEC) water splitting is one of the most promising renewable energy technique, which directly converts solar energy into storable and clean fuel, hydrogen. However, the solar-hydrogen efficiency (SHE) of PEC cell remains limited (< 1%) because of the insufficient photovoltaic and photocurrent generation of photoanodes. A clear understanding the hole quasi Fermi level (EFp) profile in the band gap is important to predict the photovoltaic and photocurrent. In this work, the solution growth metal oxide nanowires (NWs) were prepared as photoanodes for PEC investigation. My research is focused on (i) calculating hole concentration of photoanodes (TiO2 and α-Fe2O3), (ii) establishing a series of band diagrams to summarize the photocurrent generation at various bias potential, and (iii) reducing the hole transport and transfer resistance by post annealing Ti doped α-Fe2O3 for enhanced PEC performance. In addition to the energy production, the development of energy storage is also important. Supercapacitors (SCs) are one of promising energy storage technique. It can be fully charged and discharged in seconds; as a consequence, it can provide the instant power for electric vehicles. The limit of SCs is the high cost. Thus, a low cost and high power density of SCs is greatly required. MnO2 is a potential candidate of SCs because of its low cost and high theoretical specific capacitance (1370 F g-1). However, the poor electrical conductivity limits its capacitive performance. In this work, the high surface area and high conductive RuO2 NRs were used as substrate to improve the charge transport of MnO2. High specific capacitance of 793 F g-1 was achieved at a scan rate of 2 mV s-1 in 1 M Na2SO4 aqueous solution.

並列關鍵字

metal oxide ； photoelectrochemical water splitting ； supercapacitors

參考文獻

102. Glasscock, J. A.; Barnes, P. R. F.; Plumb, I. C.; Bendavid, A.; Martin, P. J. Thin Solid Films 2008, 516, (8), 1716-1724.

39. Wang, G.; Ling, Y.; Wheeler, D. A.; George, K. E. N.; Horsley, K.; Heske, C.; Zhang, J. Z.; Li, Y. Nano Lett. 2011, 11, (8), 3503-3509.

69. Hu, L.; Chen, W.; Xie, X.; Liu, N.; Yang, Y.; Wu, H.; Yao, Y.; Pasta, M.; Alshareef, H. N.; Cui, Y. ACS Nano 2011, 5, (11), 8904-8913.

109. Chueh, Y. L.; Hsieh, C. H.; Chang, M. T.; Chou, L. J.; Lao, C. S.; Song, J. H.; Gan, J. Y.; Wang, Z. L. Adv. Mater. 2007, 19, (1), 143-149.

84. Weng, Y.-X.; Wang, Y.-Q.; Asbury, J. B.; Ghosh, H. N.; Lian, T. The Journal of Physical Chemistry B 1999, 104, (1), 93-104.

國際替代計量

設計與製造金屬氧化物應用在光電化學分解水與超電容

全文下載

主題瀏覽