二硫化鉬原子層材料於產氫反應之顯微分析

Abstract

當今社會，能源上的需求極為重要，在眾多能源當中，氫氣為極具發展潛力的能源。為了更有效利用這些能源，必須尋找合適的催化劑。白金為優秀的催化劑，然而其在地球含量稀少且價格昂貴，限制了它在電解水上的應用。二硫化鉬具有良好的理論產氫效率，且地球含量豐富，為極具潛力之催化劑。此研究中之二硫化鉬使用化學氣相沉積系統成長於二氧化矽基板，透過長時間產氫反應，比較反應前後催化劑的效率改變。產氫反應造成二硫化鉬結構上的破壞，導致催化效率的下降。若以白金作為對電極，金屬沉積會改變催化劑的本質，並參與產氫反應，進而影響催化劑的效率。透過此研究，日後研究在電極的選擇上需更加注意，也對於二硫化鉬於產氫反應之穩定性更加了解。

Owing to increasing energy demands, much research has been devoted to developing sustainable energy. Among the methods for harvesting solar energy, hydrogen production through electrocatalysis or photoelectrocatalysis of water splitting is a promising one. For mass production, finding suitable catalysts for the hydrogen evolution reaction (HER) is essential. Platinum is an excellent catalyst for hydrogen production; however, the rare amount of platinum in the earth and its high price limit the use of platinum in industrial applications. Molybdenum disulfide (MoS2) is a potential candidate to replace platinum, because it is of a high theoretic catalytic efficiency and earth abundance. In this research, MoS2 atomic layers are fabricated by chemical vapor deposition (CVD) for the use as the HER catalyst. The HER efficiencies of pristine MoS2 and the MoS2 that has been through a long-term electrochemical reaction are compared. After HER, destruction of the MoS2 structure results in decreased efficiency. In addition, deposition of metal on the working electrode in the electrochemical test also affects the catalytic efficiency. This research provides more insights into the selection of electrode materials for electrochemical reactions.